Weekly Outlook: July 25-31, 2022

The final week of July will not be as hot as last week was, but there will still be episodes of humidity to deal with.

After Sunday’s record-breaking heat, which topped 100 in places, today won’t be as hot with a cold front approaching the region. We’ll have plenty of cloud cover with some showers and thunderstorms expected ahead of the front. Some of the storms could be quite potent, with strong winds, hail, and heavy downpours. There is even a risk for a tornado. While the threat of severe weather exists from Maine to Virginia, around here, we think it’ll be mostly north and west of I-95 where the strongest storms occur, as usual. We could still see some strong storms in Rhode Island and southeastern Massachusetts, so don’t let your guard down if you’ll be in that neck of the woods during the afternoon.

Severe weather looks like a decent bet across the Northeast today. Image provided Pivotal Weather.

While temperatures will be “cooler” today they’ll still be in the 80s, possibly near 90 in spots if we can get enough sunshine in the morning. Of course, if we get some sunshine, that will also help to fuel some stronger thunderstorms. It’ll also be a much more humid day, with dewpoints well into the 60s and 70s, so it’ll feel nearly as hot as Sunday was. As a result, the National Weather Service extended the Heat Advisory for much of Eastern Massachusetts and Rhode Island until 5pm today.

It will feel like it is near or over 100 degrees early this afternoon across the region. Image provided by Weathermodels.com

The cold front moves offshore tonight, then high pressure builds in for Tuesday and Wednesday with drier conditions. Temperatures should still reach the 80s, but dewpoints will be in the 50s and lower 60s. The next system approaches on Thursday, so we’ll turn warmer and more humid once again, with some showers and thunderstorms likely late Thursday into Friday. At this time, it doesn’t look like the threat for severe weather is as significant as today, but it’s still a few days away, so we’ll keep monitoring things. High pressure builds back in next weekend with seasonably warm and drier weather once again.

Tuesday will be much more comfortable with dewpoints in the 50s and lower 60s. Image provided by WeatherBell.

Monday: Some morning sun, then becoming cloudy and breezy with showers and thunderstorms likely, some of which could be strong to severe. High 85-92.

Monday Night: Showers and thunderstorms end in the evening, then skies gradually clear out. Low 59-66.

Tuesday: A mix of sun and clouds, not as humid. High 80-87.

Tuesday night: Clear skies. Low 58-65.

Wednesday: Partly sunny. High 83-90.

Thursday: Becoming partly to mostly cloudy with showers and thunderstorms possible during the afternoon and evening. High 85-92.

Friday: Partly sunny with a chance of showers. High 82-89.

Saturday: Sunshine and some afternoon clouds. High 81-88.

Sunday: Partly to mostly sunny. High 82-89.

Weekly Outlook: May 16-22, 2022

We’re starting the week with a bang, as a strong cold front may produce some severe weather today.

Once the fog near the South Coast burns off this morning, we’ll have partly sunny skies today and it will be warm and somewhat humid. However, a strong cold front will move across the region later today, bringing an end to the humidity and mild temperatures. Ahead of that front, showers and thunderstorms are expected this afternoon into part of the evening. The bulk of the severe weather should stay to our west, but some of the storms that make it this far east could still produce gusty winds, small hail, and heavy downpours.

The farther west you go, the more likely severe weather becomes today. image provided by NOAA.

Behind the front, an upper-level low pressure system will cross the Northeast on Tuesday, generating some clouds and possibly a stray shower or two. High pressure then builds in for Wednesday and Thursday with dry and seasonably mild conditions. By Friday, a warm front will move across the region, allowing warmer and more humid air to move back into the region, Saturday looks like it will be the warmest day, with temperatures possibly topping 90 in much of the region. The latter half of the weekend is a bit trickier. A cold front will move through, with some showers and thunderstorms likely, but the timing of the front is still in question, which has significant implications for the temperature forecast on Sunday. If the front moves through Sunday afternoon, as some models are showing, then another hot day is likely, but if it moves through Saturday night, as other models are indicating, then we’ll clear out after some morning showers, but temperatures will be significantly cooler. We’re going to play the middle ground for now, and hope for some clarity by the time we get to our Weekend Outlook on Thursday.

Sunday could be another hot day, but how hot? Images provided b Pivotal Weather.

Monday: Morning fog along the South Coast, otherwise a mix of sun and clouds with showers and thunderstorms developing during the afternoon, some of which may contain gusty winds, hail, and heavy downpours. High 77-84, cooler along the coast.

Monday night: Showers and storms end in the evening, skies start to clear out after midnight. Low 51-58.

Tuesday: Sunshine and some afternoon clouds, slight chance for a stray shower, breezy. High 68-75.

Tuesday night: Mostly clear. Low 45-52.

Wednesday: Plenty of sunshine, breezy again. High 65-72.

Thursday: A mix of sun and clouds. High 66-723.

Friday: Partly sunny. High 75-82, cooler along the coast.

Saturday: Partly to mostly sunny. High 86-93, cooler along the coast.

Sunday: A mix of sun and clouds with a chance for showers and thunderstorms. High 77-84.

Stormy Weather Ahead for the East

A rather potent storm system will bring a variety of weather to the eastern third of the United States over the next few days.

Low pressure is developing along a frontal system in southern Texas this evening. Image provided by the Weather Prediction Center.

Low pressure developed along a frontal system in southern Texas on Saturday, and it will slowly strengthen as it moves northeastward tonight and Sunday. As it strengthens, it will draw moisture northward from the Gulf of Mexico, while colder air continues to move southward behind the storm system. This will set the stage for a couple of rather active days across the Eastern third of the nation, with several different types of weather likely.

The GFS model shows the progression of the storm over the next few days. Loop provided by Tropical Tidbits.

The biggest threat initially will be severe weather. As the warm, moist air flows northward from the Gulf of Mexico and clashes with the colder air moving in behind the storm, strong to severe thunderstorms are possible. A few storms are possible overnight in parts of Texas and Louisiana, but the threat will shift into the Gulf Coast on Sunday, parts of the Southeast and the Carolinas Sunday night, and parts of the East Coast from Florida to the Mid-Atlantic states on Monday. Some of the stronger storms may produce heavy downpours, damaging winds, and possibly some tornadoes.

Strong to severe storms are possible from the Gulf Coast into the Carolinas on Sunday. Image provided by Pivotal Weather.

While severe weather is not common at this time of year, it is certainly not unheard of. In fact, Saturday marked the 32nd anniversary of one of the strongest tornadoes on record to hit North Carolina. On November 28, 1988, an F4 tornado tore an 84-mile path of damage across parts of North Carolina, including the city of Raleigh.

As the storm moves up the Appalachians it will bring unseasonably mild air to the East Coast, but also some heavy rainfall. Temperatures will be in the 60s and 70s across the Gulf Coast and Southeast on Sunday. By Monday, 60-degree readings will be possible as far north as southern New England, with some 70s into the Carolinas and parts of southern Virginia. The mild air may linger into Tuesday across parts of New England as well. While these temperatures are 10-20 degrees above normal, they will likely fall short of the record highs in most locations.

Monday will be a warm day by November standards up and down the East Coast. Image provided by WeatherBell.

The warm weather will be transported in by strong southerly winds ahead of the system. Sustained winds of 25-35 mph will be common up and down the East Coast. Many places could see wind gusts of 50-60 mph or stronger, which could lead to power outages as trees and wires come down.

Wind gusts in excess of 50 mph are possible across the East Coast ahead of the storm. Image provided by WeatherBell.

In addition to the warm weather, heavy rain is likely for much of the East. The warm, moist air being drawn northward from the Gulf of Mexico will be deposited up and down the East Coast later Sunday into Monday, and early Tuesday for parts of New England. Rainfall totals of 1-2 inches will be common, with some places possibly picking up 3 inches or more, especially in parts of eastern New England. While this will help put another significant dent in the long term drought that the region is experiencing, too much rain at once will likely lead to flooding in some areas.

Heavy rain is likely across the East Coast Monday into Tuesday. Image provided by Weathermodels.com

While all of this is going on ahead of the storm, a different scenario will be evolving on the storm’s back side. Colder air flowing southward from Canada will clash with the warm air, resulting in snow across parts of the Great Lakes and the Appalachians. The snow will be accompanied by gusty winds, lowering visibility in many locations, resulting in very hazardous driving conditions. While the snow won’t be exceptionally heavy, many places could receive upwards of 4-8 inches by the time everything winds down. Across the higher elevations of the Appalachians, even into the southern Appalachians, some heavier amounts are possible as well. As the systems gets caught under an upper-level low pressure system in southeastern Canada, it may produce some lake-effect snow into mid-week downwind of Lakes Erie and Ontario.

Accumulating snow is expected behind the storm system. Image provided by Pivotal Weather.

Once this system pulls away, things will quiet down across the East for a few days, but there are signs that another system could impact parts of the East next weekend.

Severe Weather Possible Today

A warm and humid airmass has been in place for a couple of days, but a cold front is approaching the region. That front may produce some strong to severe thunderstorms later this afternoon.

A severe thunderstorm watch is in effect for most of the region until 8pm. Image provided by NOAA.

After some showers and thunderstorms moved across southeastern Massachusetts and Rhode Island early this morning, some sunshine has developed, allowing temperatures to quickly warm into the 80s away from the south coast by midday. Dewpoints are in the upper 60s to lower 70s, making for a rather muggy afternoon.

Temperatures are already well into the 80s away from the South Coast at midday. Image provided by NOAA.

A cold front extends from Lake Champlain into central New York at midday. Ahead of it, showers and thunderstorms are developing rapidly. Some strong to severe storms have been moving across portions of Vermont, New Hampshire, and Maine already, and these will become more numerous as the afternoon wears on. With an unstable airmass already in place, many of the thunderstorms will become strong to severe, producing strong winds, hail, and heavy downpours.

Forecast through early Sunday morning from the HRRR model. Loop provided by WeatherBell.

The most likely time for severe weather across our area looks to be in the 2-6pm time frame. This is when we’ll have the best chance for severe weather. The front itself may not move through until 7-9pm, and there may be some additional showers and thunderstorms accompanying the front. Some of these storms may produce downpours and gusty winds, but the threat of severe weather should be significantly diminished by then. Cooler and drier air will settle in behind the front tonight, but Sunday will probably still feature plenty of clouds thanks to an east to northeast wind off the ocean. Some drizzle and a few showers are also possible, but the day won’t be a washout. Temperatures will be much cooler though, staying in the 60s for much of the region. We should start to warm up again on Monday with sunshine returning.

More Strong Winds and Rain for Monday

A rather strong storm system will wreak all sorts of havoc on a large swath of the nation through the weekend and into Monday.

Low pressure will move out of the Plains states today and into the Great Lakes later Sunday into early Monday. Loop provided by Tropical Tidbits.

Low pressure is moving into the Plains states today, producing some strong to severe thunderstorms from Texas into the Southern Plains. That’s just the start of what will be a busy few days. As the storm moves into the southern Plains tonight, showers and thunderstorms, some strong to severe, will spread from Texas into the Mississippi Valley. To the north, snow is expected across the Central Plains. Some locations could pick up 6-12 inches this weekend in a swath from Nebraska and South Dakota into parts of Iowa, southern Minnesota, and Wisconsin.

A severe weather outbreak is possible across a large portion of the South on Easter Sunday. Image provided by the Storm Prediction Center.

Easter Sunday is the day that will likely grab most of the headlines away from the pandemic for a day. As the system moves into the Ohio Valley, warm, moist air will be drawn northward from the Gulf of Mexico, and as this clashes with the cold air advancing southward behind the storm, the ingredients will be in place for a severe weather outbreak. Severe weather may be ongoing as Easter Sunday dawns across the Lower Mississippi Valley, but activity will spread eastward during the day across the Deep South and the Tennessee Valley. Some of the stronger storms may produce damaging winds, large hail, torrential downpours, and likely numerous tornadoes. The risk will continue well into the overnight hours, especially in Georgia, eastern Tennessee and western portions of the Carolinas.

The severe weather threat shifts to the East Coast on Monday. Image provided by the Storm Prediction Center.

By Monday, the system will move into Ontario, dragging a strong cold front across the Eastern United States. Warm, humid air will continue to flow northward ahead of this front, triggering more showers and thunderstorms during the morning and early afternoon from northern Florida into the Mid-Atlantic states. Some of these storms could produce hail, strong winds, heavy downpours, and some tornadoes, especially from the Carolinas to the Delmarva Peninsula.

Heavy snow is likely from Wisconsin in the Upper Peninsula of Michigan Sunday into early Tuesday. Image provided by Weathermodels.com

To the north, heavy snow will continue behind the storm from northern Wisconsin into the Upper Peninsula of Michigan and Ontario. Snowfall totals of 10-20 inches or more are likely. Winds gusting to 40-50 mph will create significant blowing and drifting of the snow, with blizzard conditions at times.

Precipitation has been below normal across much of the Northeast during the first 100 days of 2020. Image provided by the Northeast Regional Climate Center.

Here in the Northeast, the big story will be the wind. Rain will be a secondary concern, with rainfall totals of 1-2 inches possible across much of the region. Some embedded thunderstorms may produce heavier downpours, especially in western New England and eastern New York, but flooding isn’t much of a concern. Precipitation has been below normal across much of the area through a good chunk of the winter and early Spring, so we need all the rain we can get, though maybe not quite this much at once. There will be some ponding on the roadways, and some of the smaller streams may overflow, but widespread flooding shouldn’t be a problem. The wind, on the other hand, will be a major problem.

High Wind Watches are in effect for parts of the Northeast, and these will likely expand over the next 12-24 hours. Image provided by Pivotal Weather.

As the system gets cranked up in Ontario, strong southerly winds will develop across the region. These will bring milder air into the region. We won’t quite reach the 90s that will set records across Florida on Monday, but 50s and 60s are still a bit above normal for mid-April around here. Southerly winds will increase Monday morning, with sustained winds of 25-35 mph expected during the afternoon. Wind gusts of 60-70 mph or higher are expected as well. This will likely result in power outages as they take down trees that are starting to show their leaves, along with power lines. Winds should start to diminish during the evening as a cold front moves through, bringing an end to the rain and shifting the winds into the west.

Wind gusts of 60-70 mph or higher could be widespread Monday afternoon. Image provided by WeatherBell.

Conditions should improve on Tuesday as high pressure builds in with some sunshine developing, but it will still be breezy as the now-powerful storm moves into northern Quebec, where heavy snow will likely continue.

A Little Bit of Everything on Thursday

An approaching storm system will make for quite the interesting Thursday across New England.

The low pressure system that will generate severe weather across parts of the Mississippi and Ohio Valleys this afternoon and evening will head northeastward tonight, and pass right over New England on Thursday. It will produce a variety of weather across our six-state region, depending on where you’re located. Across southern New England, we’ll have heavy rain, possibly some thunderstorms, and strong winds. Across northern New England, this could turn out to be quite a snowstorm.

The High-Resolution NAM model shows the progression of the system over the next couple of days. Loop provided by Tropical Tidbits.

Starting with southern New England, we’ll see showes developing during the morning, becoming a steady rain during the afternoon. With warmer air moving at the surface, thunderstorms may develop as the system moves in. Some of these storms may produce gusty winds, and hail, as there will be plenty of cold air aloft with an upper-level low pressure system moving into the Northeast.

The Storm Prediction Center has placed most of Southern New England under a marginal risk for severe weather on Thursday. Image provided by the Storm Prediction Center.

The rain and thunderstorms should come to an end by late afternoon, but that’s only half of the threat. A cold front will cross the region, with strong winds likely behind it. Sustained winds of 20-30 mph, with gusts of 40-50 mph or higher are likely. These winds may diminish a bit overnight, but will likely pick back up on Friday as the storm continues to intensify across eastern Canada. That upper-level low pressure area will also be overhead, so we’ll have plenty of clouds and a few showers popping up. With the cold air aloft, some of those showers could produce some small hail or graupel.

Wind gusts could exceed 50 mph in places Friday afternoon. Image provided by WeatherBell.

While we are dealing with strong winds and thunderstorms, it’ll be a completely different story across northern New England. Temperatures will be much cooler across Maine, New Hampshire, and Vermont, with much of the precipitation falling in the form of snow, especially in the mountains. Some of the snow will be quite heavy, with a foot or more possible, especially across Maine and northern New Hampshire. Winter Storm Watches are in effect for parts of the region. The snow will also be accompanied by strong winds, gusts to 40 mph or more, which may create blizzard conditions at times. There’s already little travel going on due to the pandemic, but there should be even less over the next few days.

Parts of northern New England, especially Maine and northern New Hampshire, could pick up more than a foot of snow Thursday into Friday. Image provided by WeatherBell.

The snow should wind down on Friday, but with the upper-level low in place, snow showers may continue. Some of those snow showers may spread into the Berkshires as colder air works its way in. Some wet snow is even possible into the Worcester Hills and Monadnocks.

High pressure will build in for the weekend with drier weather, but our next system looks to move in on Monday. That one looks like a rain-maker right now, and it might produce a decent amount of rainfall. We’ve been a bit dry this winter, so we need all the rain we can get right now to avoid slipping into a drought.

Severe Weather Possible Today

The warm and humid conditions we’ve had for much of the region over the past several days are going to continue today, but changes are coming, and the change may not be that quiet.

There is a slight risk of severe weather across much of the region today. Image provided by the Storm Prediction Center.

A weak cold front is going to approach the region today. The front may never make it across the area before it washes out, but it will help to trigger some strong to severe thunderstorms across parts of the region today. Right now, it looks like the most likely area for strong storms is from southeastern Connecticut into Rhode Island and southeastern Massachusetts. The most likely time for the storms in this area is from 11am to 3pm,, though some storms may continue through about 7pm.

The high-resolution NAM model shows the progression of storms across the region this morning and afternoon. Loop provided by weathermodels.com

The ingredients appear to be in place for some strong to severe thunderstorms to develop across the region. There are several different indices that meteorologists look at to help determine the risk for severe weather. We won’t confuse you with most of them, nor will we bore you with how they are derived. Most of these indices are indicating that the risk for today is real and significant. One of the parameters that we will share you you is called CAPE. That stands for Convective Available Potential Energy. It’s a measure of how unstable the atmosphere is, and how much “juice” is available to fuel the storms. It’s measured in joules per kilogram, and a value over 1000 means that the atmosphere is moderately unstable. If the values reach 2500 there is strong instability, and values over 4000 are indicative of extreme instability. as you can see in the map below, values of 2000-4000 (or more) are expected early this afternoon.

The High Resolution NAM model is showing CAPE values of 2000-4000 early this afternoon across New England. Image provided by WeatherBell.

Any storms that do develop this afternoon will likely contain heavy downpours, strong winds, and hail. There is even a risk for an isolated tornado. With the heavy rain, flash flooding is also a risk. So, if you’ve got plans that involve outdoor activities, make sure you keep an eye to the sky.

So, things will be better on Sunday, right? Not so fast my friends. We’ll have an upper-level low pressure area dropping southward from Canada. So, not only will it be cooler, we’ll have some more showers and thunderstorms developing. We don’t expect most of these to become severe, but with cold air aloft, we’ll have some of these storms produce small hail across the area. This is similar to what happened last Saturday, when another upper-level low moved through. There were numerous reports of small hail across the region. So again, if you’ve got outdoor plans on Sunday, keep an eye to the sky.

Hurricanes, Severe Weather, and Snow, All at the Same Time (not the Same Place)

For the third year in a row, the “M” storm in the Atlantic is prepared to wreak havoc on a populated area, but Michael isn’t the only headline maker in the weather at the moment.

Hurricane Michael isn’t the only storm in the news, but it is the biggest threat at the moment. As of early Tuesday afternoon, Michael was centered about 335 miles south of Panama City, Florida, moving toward the north at 12 mph. Maximum sustained winds are near 110 mph, making Michael a Category 2 Hurricane. Additional strengthening is expected over the next 12-18 hours as the storm moves over the warm waters of the eastern Gulf of Mexico. Hurricane and Storm Surge Warnings are in effect for the Florida Panhandle and the Big Bend area of Florida, with Tropical Storm Warnings and Watches surrounding the Hurricane Warnings. Tropical Storm Watches are also in effect for the Atlantic coast from northeastern Florida into South Carolina.

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Michael is going to pack quite a wallop when it slams into the Florida Panhandle Wednesday afternoon. Image provided by the National Hurricane Center.

Michael is expected to make landfall in the Florida Panhandle Wednesday afternoon, likely as a Category 3 storm. Strong winds, torrential rainfall, storm surge, and some tornadoes are all possible with this storm. Unlike Florence, which hung around the Carolinas for days and dumped incredible amounts of rainfall on the region, Michael is expected to keep moving at a steady pace, emerging off the Mid-Atlantic coast by Friday morning. Rainfall totals of 5-10 inches are still expected in parts of the region, which will produce flooding in some areas, especially in Carolinas, where many areas are still recovering from Florence. Right along the coast, a storm surge of 6-12 feet is possible, especially in the Big Bend area of Florida. Fortunately, this area is not heavily populated, but for the residents that do live in this area, storm surge flooding is a significant threat.

Once it moves back into the Atlantic early Friday, it should pass well south of our area. The northern edge of the rainfall from the system could reach the South Coast, but the bulk of the heavy rain should remain well to the south.

This is the 3rd year in a row that the “M” storm is expected to result in significant damage to a populated area. In 2014, Category 5 Hurricane Matthew left a path of death and destruction across parts of Haiti, Cuba, the Bahamas, and eventually parts of the southeastern United States. Last year, Category 5 Hurricane Maria devastated the northeastern Caribbean, including Puerto Rico and the US Virgin Islands. While Michael is not expected to become a Category 5 storm, it is still expected to result in significant damage to parts of Florida and the Southeast.

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Tropical Storm Leslie has been around for near 2 weeks and still looks rather healthy. Loop provided by NOAA.

Meanwhile, in the eastern Atlantic, Tropical Storm Leslie refuses to go away. As of midday Tuesday, Leslie was centered a little more than 1000 miles west-southwest of the Azores, moving toward the south-southeast at 13 mph. Maximum sustained winds are near 65 mph. The forecast for Leslie calls for a turn more toward the east over the next few days while it strengthens back into a hurricane. Leslie is expected to remain over open waters for the next few days, and could become an extratropical storm this weekend while continuing on a general easterly track.

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Nadine is a fish storm. Nothing to worry about here. Image provided by Tropical Tidbits.

To the south, Tropical Storm Nadine as formed nearly 500 miles southwest of the Cabo Verde Islands. Nadine has maximum sustained winds near 40 mph, and is moving toward the west-northwest at 9 mph. Nadine is expected to remain fairly weak over open waters for the next several days while turning more toward the northwest. As it moves over colder water late this week and this weekend, it should weaken and eventually dissipate.

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What month is it again? 70s and 80s early in the afternoon on October 9th? Image provided by WeatherBell.

Back in the United States, unseasonably warm conditions remain in place across much of the eastern half of the nation. Temperatures are in the 70s and 80s across much of the region, which is 15 to 25 degrees above normal. A strong frontal system is located in the Plains states this afternoon, separating the warm air in the East, from much cooler weather behind it in the Plains and the Rockies. Right along this front, which hasn’t moved much for the past 24 hours, severe weather and heavy rainfall are common this afternoon.

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That’s snow in Colorado, and heavy rain along with severe weather from Texas into the Central Plains this afternoon. Loop provided by WeatherTAP.

Several tornadoes have been reported already today, including a few in the Oklahoma City area, and more are expected later today and tonight. Heavy rainfall is also expected from Texas into the Central Plains and parts of the Upper Midwest. Rainfall totals of 1-3 inches and locally heavier may produce flash flooding in some areas. Flash flood watches are in effect for much of the region.

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Several inches of snow is expected form the Plains into the Upper Midwest over the next few days. Image provided by Pivotal Weather.

On the other side of the front, where much cooler weather is in place, rain is expected to change over to snow as low pressure rides along the front and into the Midwest. Winter weather advisories have already been posted for parts of the region. Snow is already falling in parts of Colorado this afternoon, and several inches may fall over the next 36-48 hours from western portions of Kansas and Nebraska into the Dakotas and northern Minnesota.

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Some heavy rain is possible across our area on Thursday as a strong cold front approaches the region. Image provided by WeatherBell.

As the system moves eastward, it will spread some heavy rain and thunderstorms into our area on Thursday. We’re not expecting any severe weather, but some heavy downpours are possible, especially from western Massachusetts into southern New Hampshire. Some localized flooding may result. Once this front pushes offshore, much cooler weather will settle in for the Friday and the weekend.

Wet Weather and High Humidity Are Coming

You know that dry weather we’ve had for much of the Spring and Summer? How about those warm days with low humidity? Well, both will be a distant memory by this time next week.

A weather pattern that is both typical and atypical of summer at the same time is going to settle into the nation over the next several days. The typical part is that we’ll have a ridge of high pressure off the East Coast, and another one in the Southwest. The ridge off the East Coast will result in heat and humidity up and down the coastline for the next several days. The ridge in the Southwest will bring very hot conditions to the Southwest and especially the Southern Plains, where record highs are expected over the next several days. The Atypical part is across the Midwest. Normally, in between the two ridges of high pressure you’d have a trough of low pressure, but in this case, we actually have a closed upper-level low pressure system. While these are common in the fall, winter, and spring, they usually don’t occur much in the summer. This will bring cooler than normal conditions into the Midwest for the next few days.

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What is this, April? The upper-level pattern features ridges of high pressure in the Southwest and off the East Coast, and an upper-level low pressure system in the Great Lakes. Image provided by Pivotal Weather.

With high pressure anchored off the East Coast, a warm and humid pattern will set up for much of next week (and possibly longer). Notice that we said “warm”, and not “hot”. While temperatures will still be a little above normal this weekend into much of next week, highs will only be in the 80s to lower 90s for most of the Eastern US. While the temperatures won’t be that bad, humidity levels will. With high pressure anchored off the East Coast, a southerly flow will help moisture stream northward from the tropics right up the East Coast this weekend and into much of next week. Dewpoints will be in the upper 60s and 70s across the region, so even though temperatures may not be hot, it will feel oppressive across much of the region.

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Moisture will stream northward from the tropics into much of the East Coast over the next several days. Loop provided by WeatherModels.com

 

With a warm and humid airmass in place for much of the week, it won’t take much for showers and thunderstorms to develop each day. With plenty of available moisture, some of these storms will end up producing very heavy rainfall. While the map above is a forecast that shows widespread coverage of heavy rain, in many cases, the storms will be very localized. Some locations could get hit by slow-moving thunderstorms over and over, while other spots a few miles away get little to no rainfall. Across the Mid-Atlantic States, where heavy rain led to flooding during the Spring, similar conditions are possible again for the next week. Across the Northeast, things are a little different.

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That’s a lot of rain from the Carolinas northward over the next week or so. Image provided by College of DuPage.

 

Here in New England, and in New York too, much of the Spring and early summer has been very dry. Localized thunderstorms have brought heavy rain to a few spots, especially earlier this week, but overall, rainfall has been well below normal across the area. Some relief will come this weekend. A weak low pressure system will move across the region late Saturday into Sunday as an upper-level low pressure system moves into the Midwest. The surface low will bring heavy rain and some gusty winds to parts of Southern New England and southeastern New York. The heaviest rain is expected late Saturday night into early Sunday morning, so neither day should be a complete washout. Once that system moves by, a warm and humid airmass will settle in, with a daily chance for showers and thunderstorms this week. Again, some places could get drenched, and some might get missed completely. Some could see off-and-on showers and storms for 6 hours, some could get a shower that lasts 6 minutes. Basically, it’ll be like living in Florida for a week, without having to worry about looking outside and finding an alligator in your swimming pool.

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It’s been very dry across New England and New York for a few months now, with drought conditions developing. Image provided by the National Drought Monitor.

 

Think warm and humid conditions with a daily chance of thunderstorms isn’t fun? It could be worse. Normally, it’s hot across Texas and the Southwest during the summer. This week though, the ridge of high pressure that is currently setting up across the Southern Plains and Southwest will bring in temperatures that are well above normal. In fact, record highs are expected for the next several days across much of Texas, as temperatures soar past 100 across much of the state, with some locations possibly exceeding 110 degrees. Unlike when the models were forecasting those temperatures here a few weeks ago, this time it’s going to happen. The heat won’t be confined to the Lone Star State either, with triple-digit highs also expected from parts of the Lower Mississippi Valley into the Southern Plains as well as parts of Colorado and New Mexico. There won’t be much, if any, relief at night either, as low temperatures will stay in the 70s, with many locations, especially urban areas like the Dallas-Fort Worth Metroplex likely not dropping below 80 degrees for low temperatures.

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Friday looks to be the hottest day across the Southern Plains and Texas, with many record highs expected to be broken. Image provided by WeatherModels.com

 

As we head into next week, the heat will ease a bit across Texas and the Southern Plains, but the core of the intense heat will shift westward into the Desert Southwest. High temperatures will top 110 degrees across much of the area for the first half of next week, with the usual hot spots such as Lake Havasu City, Arizona; Laughlin, Nevada; and Death Valley, California likely exceed 120 degrees during some of the afternoons. Highs will also top 100 across much of interior California once again. Anyone wanna place a bet as to whether Death Valley reaches 125? Better yet, will they have a night where the temperature doesn’t drop below 100 (it’s happened before)?

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A severe weather outbreak is possible on Friday across the Ohio and Tennessee Valleys. Image provided by the Storm Prediction Center.

Meanwhile, an upper-level low pressure area will settle into the Midwest. With the clash in airmasses along a cold front, showers and thunderstorms will develop. Some of these storms will become strong to severe on Friday, especially across the Ohio and Tennessee Valleys. The main threats with any storms that develop will be strong winds, large hail, and torrential rainfall that could trigger flash flooding. Some tornadoes are also possible. The storms may start during the morning closer to the Great Lakes, with the afternoon and evening seeing the most widespread activity across the region. While activity should weaken at night, the threat of severe weather will continue across southern and eastern parts of the region.

NAM-WRF 3-km null Simulated Radar
Strong to severe thunderstorms are expected across the Midwest on Friday. Loop provided by WeatherModels.com

 

As these storms crossed the Midwest today, they produced wind gusts to 90 mph and more than 30 tornadoes across Iowa. The town of Marhsalltown was devastated by a tornado earlier today. How bad was it? We’ll end this post with the Storm Report from the National Weather Service Office in Des Moines with the description of what happened in Marshalltown:

 

REPORTS OF CATASTROPHIC DAMAGE, INCLUDING 
VEHICLES MISSING, VEHICLES OVERTURNED, TOPS
OF BUILDINGS GONE, TREES DOWN, POWER LINES,
GAS LINES, ETC...

An Active Afternoon Ahead

No, we’re not expecting anything like that across the region this afternoon, but if you’ve got outdoor plans, you may want to keep an eye to the sky – we’ve got thunderstorms coming, and some of them could be strong to severe.

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It’s a little humid for mid-May, but temperatures in the 70s to lower 80s at midday are pretty nice. Image provided by NOAA.

We’ve got a rather nice day in progress across the region, but changes are coming. At midday, temperatures are generally in the 70s to lower 80s away from the coastline, where seabreezes are keeping temperatures in the 50s to lower 60s. Dewpoints are creeping up, generally in the 60s now, which is humid by mid-May standards. We’ve also got plenty of sunshine, so temperatures should continue to climb into the afternoon. However, a cold front is starting to approach from the west. An area of showers and thunderstorms is moving into western Massachusetts at midday, and though these should weaken, they will spread cloud cover in, with some rain possible across northern Massachusetts and southern New Hampshire early this afternoon.

HRRR
The HRRR simulates what the radar should look like as we head through the afternoon and evening. Loop provided by WeatherModels.com

As that cold front approaches, a stronger line of thunderstorms is expected ahead of it. As you can see in the radar simulation above, this line should enter our region during the 5-8pm time frame, also known as the evening rush hour. Some of these storms will contain strong winds, heavy downpours, and frequent lightning. That will likely make the commute home for many people even worse than normal.

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There is a moderate risk of severe weather across much of interior Southern New England this afternoon. Image provided by the Storm Prediction Center.

If it were just rain, wind, and lightning, it wouldn’t be a big deal. The problem is, it might be more than “just rain wind, and lightning.” Well away from the coastline, conditions will be favorable for severe thunderstorms to develop ahead of the front. As we mentioned in our Weekly Outlook, we still think the best odds for severe weather are from the Mid-Atlantic states into southeastern New York and western New England, but some severe storms could survive into eastern New England late this afternoon and evening. These storms should start to weaken quickly as they approach the coastal plain, but from interior Rhode Island into Central Massachusetts, the I-495 Belt of eastern Massachusetts, and Southern New Hampshire, we could see some fairly strong thunderstorms. We’ve already mentioned the frequent lightning and heavy downpours, but in the places we just mentioned, winds could gust to 60 mph or more with some of the stronger storms, which could result in more damage to places that already had lots of tree damage earlier this month.

Tornado
There is a low chance for a tornado or two this afternoon with some of the stronger storms. Image provided by the National Weather Service.

In addition to the threats we listed in the last paragraph, there is also a low (but non-zero) threat for am isolated tornado or two this afternoon. No, we’re not expecting a tornado outbreak, but a brief tornado or two could spin up, especially across central and western portions of New England. In fact, if we do get one, it wouldn’t even be the first one this year in New England. Just last night, we found out that on May 4, a tornado tracked 35 miles through mostly (but not all) rural western and central New Hampshire.

GFS 50-STATES USA Mass & CT & RI 2-m Maximum Temperature 36
Temperatures on Wednesday will be 20-30 degrees cooler than today. Image provided by WeatherModels.com

Behind the front, Wednesday will be a much cooler day. Easterly winds and some cloud cover will keep temperatures in the 50s along the coast, lower 60s inland. Sunshine and warmer temperatures will return on Thursday, so you’ll only have one day to complain about.