Month: July 2016

The Tropics Are Getting Active Again

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As we approach the end of July, tropical cyclone activity normally starts to ramp up across both the Atlantic and the Pacific. This year, that is the case once again, with one active system right now and three other areas of disturbed weather that are being monitored for development.

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Forecast track for Tropical Depression 06z. Image provided by the Joint Typhoon Warning Center.

The only active tropical system right now is located in the Western Pacific Ocean. Tropical Depression 06W formed Friday afternoon about 450 miles east-southeast of Manila in the Philippines. The system is expected to steadily strengthen on Saturday, likely becoming Tropical Storm Nida. The current track calls for the system to become a typhoon before passing very close to northern Luzon on Sunday. This track will likely bring very heavy rainfall to northern portions of Philippines. Rainfall totals of 10 to 20 inches are possible, with some heavier amounts. Flooding and mudslides are likely across this area. After passing near or over northern Luzon this weekend, the storm will head west-northwestward into the South China Sea. A track towards southern China seems likely, with a landfall near Hong Kong possible. Flooding has been reported in southern China recently from heavy monsoonal rains, and additional heavy rain from a tropical system will likely worsen flooding in the region.

Heading eastward, a cluster of showers and thunderstorms centered about 750 miles south-southwest of Cabo San Lucas, Mexico is being watched for signs of development. Although the shower activity is disorganized right now, conditions are favorable for the development of a tropical depression this weekend. Some slow but steady strengthening is expected into early next week. The system will not be a threat to any land areas.

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Model forecasts for the track of a tropical disturbance in the Eastern Pacific. Image provided by NCAR.
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Model forecasts for the intensity of a tropical disturbance in the Eastern Pacific. Image provided by NCAR.

In the Atlantic, after a record-setting start to the season, things have been quiet throughout the month of July. As we flip the calendar into August, that could change.

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There are two disturbances in the Atlantic that are being monitored for development. Image provided by the National Hurricane Center.

During the first part of hurricane season (June/July), attention is mainly focused on the Gulf of Mexico, Caribbean, and the Bahamas for tropical development. These are the areas where water temperatures are warm enough to sustain tropical systems, but also areas where conditions are usually more favorable for systems to develop. Out across the open waters of the Atlantic, strong easterly winds can bring surges of Saharan dust off of Africa and send them across the Atlantic towards the Caribbean. This dry, dusty air inhibits the development of thunderstorms. As we get into August, the easterlies usually calm down a bit, and tropical waves start rolling off of Africa every few days. Some of these waves look impressive as they exit the coast, with plenty of shower and thunderstorm activity, only to quickly collapse when they hit the colder waters right off the coast of Africa. Others survive that part of the trip and make their way across the Atlantic. The ones that develop quickly into tropical systems are known as “Cape Verde Storms”, since the often form not far from the Cape Verde Islands. With plenty of time to cross the Atlantic, some of these storms are the most powerful storms we’ve seen.

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Location of all tropical storms and hurricanes that formed between July 21 and 31 during the years 1851-2009. Image provided by the National Hurricane Center.

Right now, there are two areas of disturbed weather we’re watching in the Atlantic. One of these is a cluster of thunderstorms passing south of the Cape Verde Islands. Although the system is disorganized at the moment, conditions are favorable for some development this weekend. As we head into the beginning of next week, conditions look less favorable. Most of the forecast models indicate that the system should remain weak, if it develops at all, and remain over open waters, with no threat to any land areas.

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Model forecasts for the track of a tropical disturbance near the Cape Verde Islands. Image provided by NCAR.
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Model forecasts for the track of a tropical disturbance near the Cape Verde Islands. Image provided by NCAR.

The second disturbance is the one that bears watching, and will have impacts on land areas. A tropical wave is centered about 1000 miles east of the Lesser Antilles this evening, producing disorganized showers and thunderstorms. The wave is moving along rather quickly (around 20-25 mph), and this fast motion will likely preclude much development over the weekend. The wave will bring showers and thunderstorms along with gusty winds to the islands of the eastern and northeastern Caribbean this weekend. Parts of this region are still recovering from a drought, so the rainfall will be welcome. As this system moves into the Caribbean, we’ll need to keep a close eye on it. Some models have the center of the system pass north of the islands, and towards the Bahamas, some have it pass directly over the islands, and others have it pass south of the islands and across the Caribbean, then possibly towards the Gulf of Mexico. The exact track it takes will determine whether it has a chance to develop or not. At this time, it’s far too early to tell which way it will go, so we’ll need to keep an eye on it.

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Model forecasts for the track of a tropical disturbance in the Central Atlantic. Image provided by NCAR.

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As we head into August, tropical activity should continue to ramp up across the Atlantic and the Pacific as we head towards the peak of the season, which is usually from late August to late September.

Beneficial Rain? Not For Most of Us

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Last night, we told you about the old adage “When in Drought, Leave It Out.” Well, a lot of meteorologists around here decided to ignore that because many of the computer models were forecasting heavy rain across Southern New England on Friday. If you checked out a forecast anywhere on TV, Radio, or the Internet, all you heard was that heavy rain was expected on Friday. However, our forecast, along with the one from our comrades at Woods Hill Weather, was for most of the heavy rain to remain to our south. Well, most of the computer models started leaning that way today as well, and all of the other forecasts started to backpedal off of their “heavy rain” forecasts.

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GFS model forecast for rainfall through early Saturday morning. Image provided by WeatherBell.
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NAM model forecast for rainfall through early Saturday morning. Image provided by WeatherBell.

As you can see in the maps above there will be a sharp cutoff from heavy rain to very little rain across the region. We’re confident that heavy rain will fall along the south coast on Friday, and we’re fairly confident that the heavy rain shouldn’t make it as far north as Boston. Areas in between Boston and Providence? That’s a toss-up. A Flash Flood Watch is in effect for most of Southeastern Massachusetts, Rhode Island, and Connecticut through Friday evening. Some flooding is likely with some of the heavier downpours, especially in some of the places that usually experience flooding in heavy rain. Unfortunately, not much rain is expected in the areas that really need it, especially the Merrimack Valley.

In yesterday’s post, we also mentioned the possibility of the tropics heating up. We told you about the tropical disturbance that was being watched in the eastern Atlantic. Well, we’re still watching it today, but we also have our eyes on a second area of disturbed weather out there.

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We have not one, but two disturbances to keep an eye on now. Image provided by the National Hurricane Center.

The first disturbance is passing south of the Cape Verde Islands this evening. It remains weak, but conditions are favorable for some development over the next few days. However, that window of opportunity will likely start to close as the system gets into the central Atlantic by the end of the weekend. Most of the forecast models don’t expect much development of this system, and frankly, neither do we. It’s something to keep an eye on through the weekend, but we’re not expecting much.

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Model forecasts for the track of a tropical disturbance south of the Cape Verde Islands. Image provided by Tropical Tidbits.
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Model forecasts for the intensity of a tropical disturbance south of the Cape Verde Islands. Image provided by Tropical Tidbits.

Meanwhile, farther to the west, another disturbance is about halfway between Africa and the Caribbean, and quickly heading westward this evening. The fast movement will likely preclude much development for now, but it should bring some gusty winds to the Lesser Antilles this weekend. Assuming it survives that long, we will need to keep an eye on it. As you can see below, many of the tropical models bring in just north of the Islands and into the Bahamas. There are other models that bring the system into the Caribbean and possibly the Gulf of Mexico well down the line. There are others that don’t expect the system to survive more than a few days.As the system gets closer to the Caribbean, we should start to get a better idea of what it might do and where it might go. Until then, it’s just something to keep an eye on.

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Model forecasts for the track of a tropical disturbance in the Central Atlantic. Image provided by WeatherBell.
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Model forecasts for the intensity of a tropical disturbance in the Central Atlantic. Image provided by Tropical Tidbits.

 

“When in Drought, Leave it Out”

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“When in Drought, Leave it Out”

We don’t know who first coined that phrase, but like most meteorological rules of thumb, it tends to hold true most of the time. Here in New England, especially Southern New England, we are definitely in a drought.

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Latest update from the U.S. Drought Monitor.

A persistent pattern has led to warm and dry conditions across the Northeast for the past several months.While scattered showers and thunderstorms have produced locally heavy rainfall in some areas recently, widespread rainfall has been lacking. Many cold fronts have come across the region with little rainfall and coastal storms are rare in the summer to begin with. Even waves of low pressure passing south of New England along stalled out cold fronts have been too far south to produce much rain across our area.

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Rainfall since the start of April has been well below normal across the region, especially in the Merrimack Valley. Image provided by the Northeast Regional Climate Center.

 

The dryness has been most noticeable since the beginning of June. Since June 1, Boston’s Logan Airport has recorded just 1.99″ of rain. This is the driest June/July on record in the city. The current record is 2.03″ from 1949. If Boston does not receive more than 0.04″ before Sunday night, a new record will be set (more on that later). In Worcester, the 3.18″ during the same timeframe is the 4th lowest total on record. In Lowell, 3.12″ of rain has been reported since June 1. This is the 8th lowest total on record.

So, is there any relief on the way? Maybe, though we wouldn’t count on it. A cold front will move across the region late Thursday and early Friday, then stall out south of New England. A wave of low pressure will ride along the wave, passing south of us on Friday. This wave will produce locally heavy rain and thunderstorms across the Ohio and Tennessee Valleys on Thursday, before it heads for the Mid-Atlantic states Thursday night. The question then is, how far north does the low and its associated rain shield get? This is the same situation we often see in the winter when trying to determine if a storm will miss us completely, bury us with heavy snow, or come too close and give us rain instead of snow. Thankfully, we don’t have to worry about snow for another 3-4 months at least.

Right now, there are several different solutions among the models, which have a rather large impact on the forecast.

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GFS model forecast for total rainfall through Saturday night. Image provided by WeatherBell.
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GEM (Canadian) model forecast for total rainfall through Saturday night. Image provided by WeatherBell.
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NAM model forecast for total rainfall through Saturday night. Image provided by WeatherBell.

For the past few months, as we’ve mentioned previously, most of these storms have passed too far south to have much of an impact on us. For this reason, we’re inclined to lean that way with the forecast for Friday as well. That means we’re going with the GFS model above. Is there a possibility that one of the other models is right and we do get heavy rain? Sure, they could very well be right, but we’re not betting on it.

Droughts feed on themselves, which is how the expression at the top of the page came into existence. When the ground is dry, there is even less moisture available for approaching systems. When there’s less moisture available, less rain falls. When less rain falls, the drought gets worse. So how do we break the drought? When we have one in the summer, usually, the answer is with a tropical system. Either a tropical storm/hurricane comes up the coast and slams into New England dumping copious amounts of rain on us, or one hits farther down the coast (North Carolina or the Gulf) and weakens inland and the remains of it move this way with heavy rainfall. The Summer of 1955 was hot and dry like this one has been. Then, in the span of a week in August, two Tropical Storms (Connie and Diane) brought record rainfall to the region, with widespread flooding. Of course, that’s not the scenario we prefer. A more gradual transition to a wetter pattern is the best case scenario, but that isn’t how is usually works.

So, right now, you’re probably asking “is there a tropical system heading our way?” No, there isn’t, not yet. Since our record-setting June, there hasn’t been any activity at all in the Atlantic in July, but that could be changing. A tropical wave moved off the coast of Africa on Tuesday, producing plenty of shower and thunderstorm activity. Although some of that activity diminished today, conditions are still favorable for some development over the next few days. The odds of the system becoming a tropical depression are still fairly low, and the odds of it impacting any land, let alone New England, are still fairly remote.

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Model forecasts for the track of a tropical disturbance in the Eastern Atlantic. Image provided by the University of Wisconsin.
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Model forecasts for the intensity of a tropical disturbance in the Eastern Atlantic. Image provided by the University of Wisconsin.

Now that we’re approaching the beginning of August, these waves should start to move off the coast of Africa every few days. At least a few of these will eventually become tropical systems as we approach the peak of hurricane season, which is late August into late September. Another area to watch is down near the Bahamas. Sometimes tropical systems form in this region, and they can quickly strengthen and head up the coast within a couple of days, which is exactly what Hurricane Bob did in August of 1991.

For now, do your rain dance and pray for rain to save your garden or lawn. It doesn’t look like any beneficial rain is coming anytime soon (unless the NAM is right on Friday).

Weekly Outlook July 25-31, 2016

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How many of you enjoyed the heat and humidity last week? You’re in luck! We’ve got more coming! How many of you enjoyed the severe weather last week? Guess what? There’s more of that coming too! Yup, it’s another summer week here in New England.

 

We start off with Monday, which will be hot and humid after a warm front crosses the region. As a cold front start to approach from the northwest later in the day, it will likely trigger thunderstorms across the region. Some of these storms could be strong to severe, so if you’re planning to be outside late in the day, keep an eye to the sky. The front moves through and then Tuesday is much drier, but still hot. High pressure keeps it hot on Wednesday too.Another front comes through on Thursday, with some additional showers and thunderstorms possible. After that, things get tricky. The front stalls out south of New England and a wave of low pressure rides along it, likely giving us some additional showers and thunderstorms on Friday. The big question is next weekend. Does another wave of low pressure ride along the front, giving is more showers along with cooler conditions, or does high pressure build in, pushing the front farther to the south? We’ll be optimistic for now, and go with high pressure building in, but keep in mind that this could change.

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Forecast from the GFS model for dewpoints (colors) and lifted index (a measure of instability in the atmosphere) for 5pm Monday. Image provided by College of DuPage.

Monday: Becoming cloudy with showers and thunderstorms developing late in the day. Humid. High 88-95.

Monday night:Showers and thunderstorms taper off in the evening followed by clearing skies. Low 67-74.

Tuesday: Plenty of sunshine with a few clouds.Drier. High 88-95.

Tuesday night: Clear skies. Low 63-70.

Wednesday: Partly to mostly sunny. High 88-95.

Thursday: A mix of sun and clouds with a few showers and thunderstorms possible in the afternoon. High 90-97.

Friday: More clouds than sunshine with additional showers and thunderstorms, especially south of Boston. High 79-86.

Saturday: Partly to mostly sunny.High 77-84.

Sunday: A mix of sun and clouds. High 76-83.

Trouble in Paradise? Tropical Storm Darby Threatens Hawaii

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After a rather slow start to the Hurricane Season, the Eastern Pacific has gotten very active, setting records in the process.

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Satellite photo of the Eastern Pacific showing 4 active tropical cyclones (from Left to Right: Darby, Estelle, Georgette, Frank). Image provided by NOAA.

Late Friday morning, Tropical Depression Eight-E strengthened into Tropical Storm Georgette, the seventh named storm to form in the Eastern Pacific this month. This ties July of 1985 for the record for most storms to form during the month of July in the Eastern Pacific. as of 8am PDT, Georgette was centered about 870 miles south of Cabo San Lucas, Mexico, moving toward the west-northwest at 13 mph. Georgette had maximum sustained winds near 45 mph, and additional strengthening is expected. Georgette could become a hurricane this weekend while moving across the open waters of the Eastern Pacific Ocean.

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Computer model forecasts for the track of Tropical Storm Georgette. Image provided by Tropical Tidbits.

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Closer to Mexico is Tropical Storm Frank. As of 8am PDT, Frank was centered about 235 miles west-southwest of Manzanillo, Mexico with top winds near 50 mph, moving towards the northwest at 14 mph. Frank is expected to continue moving toward the northwest this weekend with some additional strengthening possible. Frank could become a hurricane before a weakening trend starts. By the end of the weekend, Frank is expected to start weakening while moving over colder waters west and southwest of Baja California. While Frank does not appear to be a threat to land at this time, anyone with interests in the Southern Baja Peninsula should monitor Frank’s progress, in case it tracks a bit farther east of the current projections.

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Satellite loop of Tropical Storm Frank. Loop provided by NOAA.

To the west, Tropical Storm Estelle was centered about 1500 miles west of Cabo San Lucas, Mexico as of 8am PDT. Estelle continues to weaken, with maximum sustained winds down to 40 mph. Estelle is expected to dissipate over the open waters of the Eastern Pacific this weekend.

Despite all the activity in the Eastern Pacific, most of the attention is centered on the Central Pacific Ocean, where Tropical Storm Darby is bearing down on Hawaii.

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Satellite photo and track forecast for Tropical Storm Darby. Image provided by NOAA.

As of 5am HST, Darby was centered about 390 miles east of Hilo, HI moving toward the west at 12 mph. Maximum sustained winds have decreased to near 60 mph, and some additional weakening is expected. Darby is expected to turn more towards the northwest this weekend, passing very close to or right over portions of the Hawaiian Islands. A Tropical Storm Warning has been issued for the island of Hawaii, and a Tropical Storm Watch has been issued for the islands of Maui, Molokai, Lanai, and Kahoolawe. While Darby may bring gusty winds, possibly to 50 mph at times, to portions of Hawaii this weekend, the main threat will be rainfall and resultant flooding. Rainfall totals of 5-10 inches are possible, with some heavier amounts expected. Conditions should improve across the islands by Monday as the storm pulls away from the region and continues to weaken.

Weekly Outlook July 18-24, 2016

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The upcoming week can be described fairly easily. We’ll start off hot, cool off just a bit, gradually get hot again, and then get REALLY hot next weekend. oh sure, there might be a few thunderstorms on Monday, again on Friday, and possibly next Sunday, but the key word there is few. As in, don’t count on getting one to cool you off. And certainly don’t count on helping alleviate the drought any time soon.

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Heat Index forecast for 3pm Monday from the NAM model. Image provided by WeatherBell.

A cold front will cross the region today. Before it does though, with plenty of sunshine, temperatures will jump into the lower to middle 90s. When you factor in the humidity, the heat index will be in the middle to upper 90s across the region. As a cold front slices through this airmass in the afternoon, it will trigger showers and thunderstorms, some of which could be strong to severe. As is usually the case, the best chance for severe weather will be north and west of Boston. As the line of storms gets closer to the coastline, it will likely start to fall apart. High pressure then builds in for Tuesday, with cooler air behind the front. However, as the high moves offshore, south to southwest winds will allow temperatures to gradually warm up as the week goes on, with highs getting back into the 90s by late in the week. Another front will approach the region on Friday with another chance for showers and thunderstorms. After that, many of the models are indicating the possibility that the weekend, especially Sunday, could be hot. When we say “hot”, we mean “HOT”, as in, there is a chance that the high temperature in some places might be include a 3rd digit and begin with the number 1. Several of the models have been showing a signal for hot weather next weekend, but as always, timing is everything. Another front will be approaching the region, with the possibility of more showers and thunderstorms. Not only will the timing of the front be a big factor in the development of showers and storms, but it will also have an impact on how hot it gets. We should have more clarity on that as the weekend gets closer.

Monday: A sunny start, then clouds move in with showers and thunderstorms developing in the afternoon. Some of the storms could be strong to severe, with strong winds, hail, torrential downpours, and possibly even a tornado. High 88-95.

Monday night: Showers and thunderstorms taper off in the evening, followed by clearing skies. Low 63-70.

Tuesday: Sunshine and a few clouds. High 77-84.

Tuesday night: Mostly clear. Low 54-61.

Wednesday:Mostly sunny. High 77-84.

Thursday: Sunshine and some afternoon clouds. High 83-90.

Friday: Partly sunny, chance for showers and thunderstorms. Humid. High 88-95.

Saturday: A mix of sun and clouds. High 89-96.

Sunday: Partly sunny, chance for showers and thunderstorms. Humid. High 92-99.

The Heat is On, But is It a Heat Wave?

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(Editor’s Note – This post was originally written for the blog hosted by the University of Massachusetts-Lowell Meteorology Program. This is the reason for the references to Lowell so often. For more information about the UML Weather Center, please visit their homepage at http://storm.uml.edu/)

A Heat Wave. Triple H weather.Bad Hair Days. The Dog Days of Summer. Whatever you like to call it, it’s something we have to deal with every year, though not nearly as much in New England as other parts of the country.

According the American Meteorological Society’s Glossary of Meteorology, the official definition of a heat wave is :”A period of abnormally and uncomfortably hot and usually humid weather.”

The glossary adds further:

“To be a heat wave such a period should last at least one day, but conventionally it lasts from several days to several weeks. In 1900, A. T. Burrows more rigidly defined a “hot wave” as a spell of three or more days on each of which the maximum shade temperature reaches or exceeds 90°F. More realistically, the comfort criteria for any one region are dependent upon the normal conditions of that region. In the eastern United States, heat waves generally build up with southerly winds on the western flank of an anticyclone centered over the southeastern states, the air being warmed by passage over a land surface heated by the sun.“

How often do we have an actual heat wave here in New England? For Lowell, we average 2 heat waves per year. The most common time for one is between the middle of June and middle of August, but they have occurred as early as the middle of April and as late as late September. In the summer of 1955, we actually had 8 separate heat waves between the end of June and late August. The worst of the bunch was 9 day heat wave that started on June 30 and ended on August 7. On 3 of the 9 days (July 31, August 4, August 5), the high temperature was 100 degrees.

So far, we have not had a heat wave in Lowell in 2016. We had one in 2015, a 3 day stretch from September 7-9, but 2014 also did not feature a 3-day stretch of temperatures above 90.

While a 3-day stretch of 90-degree weather isn’t that uncommon around here, a string of 7 or more days in a row is. In fact, in the 125 years of climate data we have for Lowell, we’ve had a stretch of 7 consecutive days above 90 degrees just 20 times. The last time it happened was just 3 summers ago – July 14-20, 2013. Longer stretches are even rarer. We had a 10-day stretch of 90-degree temperatures from August 27 through September 5, 1953. This occurred just one year after a brutal 13-day stretch from July 11-23, 1952 that featured 4 days with highs above 100 degrees. The worst heat have in Lowell though was a 15-day stretch from August 1 through 15, 1988 which capped off one of the hottest summers in Lowell history.As if having 15-days of 90-degree weather isn’t tough enough, 11 of those days featured highs of 96 or higher, one (August 3) had a high of 100, and most of those days were accompanied by high humidity, with dewpoints well into the 60s and 70s.

While there have been many memorable heat waves in New England, there’s only one day that is known simply as “The Hot Day”. On August 2, 1975, a ridge of high pressure settled into the Northeast. August 1 was hot in its own right, reaching 102 for a high here in Lowell. Temperatures didn’t drop much that night, with the stifling airmass in place. The low temperature on August 2 here in Lowell was only 79, the warmest low temperature on record here. With temperatures already starting the day so warm, and plenty of sunshine, it didn’t take much to send temperatures to levels that had never been seen around here before. On Nantucket, the high hit 100 for the only time on record. Providence, Rhode Island reached 104, setting a new state record. In Massachusetts, a new state record of 107 was set in both Chester and New Bedford. Here in Lowell, our records show a high of 108 was recorded that day, but this seems suspect. High temperatures from other nearby spots that day included 105 in Reading, 103 in Pepperell, 103 in Haverhill, 101 in Lawrence, 100 in Nashua, and 99 in Dracut.

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Daily Weather Map for August 2, 1975. Image provided by NOAA.

Luckily, 100-degree heat isn’t common around here. On average, we hit 100 here in Lowell about once every 4 years.The last time it occurred was on July 22, 2011, when we reached 102. In both 1911 and 1952, we reached 100 degrees 5 separate times. 90-degree days occur and average of 14 times per year.So far in 2016, we’ve had 4 days with highs of 90 or higher.1932 is the only year on record in Lowell where the high temperature failed to hit 90 degrees.On the other hand, 1955 saw an incredible 46 days with highs of 90 or higher, just ahead of the 45 such occurrences in 1983.

Whether we hit 90 or not today is still to be determined (the temperature in Lowell was 87 at the time of this being written), but it certainly seems like there are more 90-degree days in our immediate future. The GFS model is showing the possibility of high temperatures in the lower to perhaps middle 90s Sunday and Monday ahead of a cold front, then the possibility of more heat late in the week.

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High temperature forecast for Monday July 18 based on the GFS model. Image provided by WeatherBell.

 

Weekly Outlook July 11-17, 2016

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Since summer tends to be much shorter around here than in other parts of the country, we tend to cherish our summer weekends. Firing up the grill, heading to the pool/beach, or just some general outdoor activities are common. So when we get a weekend in July like the one we just had, with plenty of cloudcover, showers, and temperatures holding in the 60s, it makes it feel even worse than it really is. The good news is that now that the weekend is over, things will improve! High pressure will build in, with sunshine and warm temperatures returning. In fact, it will get hot and humid later in the week, with temperatures likely soaring past 90 degrees across much of the region.

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Maybe the fog wasn’t quite this thick, but it wasn’t a great weekend.

What about next weekend? Well, that might be a bit up in the air. We’re hoping for nice weather, but at this point, we can’t guarantee it. One model says that Saturday might be a washout. However, even the previous run of this model showed a nice day for Saturday, so we’re inclined to lean towards that instead. Remember though, several models showed a week ago that this past weekend was going to be sunny and hot. This is why forecasts beyond 5 days can be very tricky sometimes.

Monday: A mix of sunshine and clouds, slight chance for a popup shower. High 74-81.

Monday night: Becoming mostly clear. Low 56-63.

Tuesday: Partly to mostly sunny. High 81-88.

Tuesday night: Clear to partly cloudy. Low 61-68.

Wednesday: Sunshine and some afternoon clouds. A few showers and thunderstorms may develop. Becoming humid. High 86-93.

Thursday: Partly sunny. Humid. High 85-92.

Friday: A mix of sun and clouds, chance for a few showers and thunderstorms. Hot and humid with a high of 88-95.

Saturday: A mix of sun and clouds. A shower or thunderstorm can’t be ruled out at this point. High 82-89.

Sunday: Partly to mostly sunny. High 81-88.

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Before you complain about how bad the weather was this weekend around here, think about this – up to a foot of snow is expected across the higher elevations of Montana, Idaho, and Wyoming today. Image provided by WeatherBell

The Pacific is Getting Active. The Atlantic? No So Much.

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After a very quiet start to the season, the Pacific Ocean is starting to get active.

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Satellite loop of Super Typhoon 02W (Nepartak). Loop provided by NOAA.

Super Typhoon 02W (Nepartak) has been gathering strength while crossing the Western Pacific Ocean for the past few days. After peaking with top winds near 170 mph on Wednesday, some slight weakening has occurred today, with winds decreasing to near 160 mph. Unfortunately, only a little additional weakening is expected before the storm makes landfall in Taiwan late Thursday.

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Radar image of SuperTyphoon 02W (Nepartak) approaching Taiwan. Image provided by yhe Taiwan Central Weather Bureau.
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Forecast track for SuperTyphoon 02W (Nepartak). Image provided by the Japanese Meteorological Agency.

After crossing Taiwan, the storm will steadily weaken before moving into eastern China. While wind and storm surge will still be threats along the coast, the bigger threat to much of the region will be heavy rainfall and the resulting flooding. Recent heavy rain has already created flooding that result in the dozens of deaths across the region. Another 5 to 10 inches or more is expected with the storm, likely worsening conditions across the region.

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GFS model forecast for rainfall through the weekend across Taiwan and eastern China. Image provided by WeatherBell.

Meanwhile, in the Eastern Pacific, there are currently two active storms, though neither is a threat to land.

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Satellite loop of Hurricane Blas. Loop provided by NOAA.

Hurricane Blas peaked on Tuesday night as a Category 4 Hurricane with top winds near 140 mph. As of Thursday afternoon, Blas was centered a little more than 1200 miles west-southwest of Cabo San Lucas, Mexico with top winds near 120 mph, making it a Category 3 Hurricane on the Saffir-Simpson Scale. Blas is moving towards the west-northwest at 10 mph, and Blas is expected to continue heading across the open waters of the Eastern Pacific while steadily weakening over the next few days.

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Current forecast track for Hurricane Blas. Image provided by the National Hurricane Center.

Closer to Mexico is Tropical Depression Four-E, which formed late Wednesday. As of midday Thursday, the depression was centered about 700 miles south of Cabo San Lucas, Mexico with top winds near 35 mph. The depression was heading towards the west-northwest at 8 mph. The forecast for the system is for it to continue heading away from Mexico and out into the open waters of the Eastern Pacific over the next few days. The system could become a Tropical Storm in the next 24-36 hours, at which point it would be given the name Celia.

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Computer model forecasts for the intensity of Tropical Depression Four-3. Image provided by Tropical Tidbits.
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Computer model forecasts for the track of Tropical Depression Four-3. Image provided by Tropical Tidbits.

While the Pacific is active, the Atlantic has quieted down after a record-setting June. A large area of high pressure continues to dominate the region, suppressing most of the tropical waves well to the south. In additional, strong easterly winds keep sending surges of Saharan Dust across the region, which inhibits thunderstorm development. Conditions should remain quiet across the Atlantic into next week.

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Satellite loop of the Atlantic Ocean. Loop provided by NOAA.

Weekly Outlook July 4-10, 2016

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Happy Fourth of July from Storm HQ!

 

A few days ago, some of the models were starting to indicate that a prolonged period of hot weather was heading out way for the latter half of this week and into the following week. Well, the models have changed their tune, and it doesn’t look like we’re going to have several days in the upper 90s to lower 100s now. Oh there will still be a couple of warm to hot days, but not many.The other thing the past few months have been lacking is rainfall, and it’s starting to become a problem. There is some in the forecast, but not a lot. We really need a lot, though not at once, as that would create other problems. Overall though, if you’re on vacation this week, things will be pretty nice.

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The GFS thinks we could see some beneficial rainfall on Tuesday across parts of the region. Image provided by WeatherBell.
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The WRF thinks that Tuesday might end up dry for parts of eastern New England. Image provided by WeatherBell.

We start the week with a fantastic holiday – sunshine and warm temperatures. Perfect for a cookout, heading to the beach/lake/pool, shooting off fireworks, or all of the above. Tuesday looks “iffy” right now. A system will pass south of New England, but how far south is still up in their air. Some showers and thunderstorms are certainly possible, especially south of Boston. The farther north you go, the more likely you’ll stay dry. High pressure returns on Wednesday, then things get “iffy” again. A series of disturbances will move along the jet stream and across New England for the end of the week and the weekend. Timing these storms isn’t easy, and while our forecast will reflect the uncertainty with a chance of showers and thunderstorms each day, for the most part, things will be good, with none of the days being a washout.

Independence Day: Plenty of sunshine, fading behind some late-day high clouds. High 82-89.

Tonight: Becoming mostly cloudy, chance of showers towards morning, mainly south of Boston. Low 59-66.

Tuesday: Mostly cloudy with showers and a few thunderstorms possible, especially south of Boston. High 80-87.

Tuesday night: Clearing skies.Low 61-68.

Wednesday: Partly to mostly sunny.High 88-95.

Thursday: A mix of sun and clouds, chance for afternoon showers and thunderstorms, mainly north and west of Boston. High 85-92.

Friday: Partly sunny, chance for a few showers and thunderstorms. High 78-85, coolest along the coast.

Saturday: Intervals of clouds and sunshine with a chance for showers and thunderstorms. High 77-84..

Sunday: Partly sunny with a chance for showers and thunderstorms. High 80-87.