3:20 PM | "Derecho-look" to the shower/thunderstorm threat around here late tomorrow night/early Thursday

Discussion

Showers and scattered strong thunderstorms are affecting the Mid-Atlantic region this afternoon and will continue to do so this evening, but perhaps an even more impressive threat is headed this way for late Wednesday night and early Thursday. In fact, this next threat has a “derecho-look” to it as an organized area of heavy showers and strong thunderstorms is likely to move hundreds of miles from the middle of the country to the Ohio Valley and then right towards the I-95 corridor. As far as the timetable is concerned, this well organized cluster of showers and thunderstorms will likely affect Iowa/Illinois late tonight and early Wednesday, and then it should reach Ohio and western Pennsylvania late tomorrow and early tomorrow night, and then it will likely make a move right towards the I-95 corridor from DC-to-Philly-to-New York City late tomorrow night and early Thursday. If indeed this cluster of heavy showers and strong thunderstorms holds together as it moves from the Ohio Valley to the east coast late tomorrow night and early Thursday, the result here could be torrential rainfall with potentially damaging wind gusts. Stay tuned. The 12Z GFS computer model forecast shows quite clearly the heavy precipitation area early Wednesday (map above) and then later Wednesday (map below) as it moves in a general east-to-southeast direction towards the east coast.

7:00 AM | Showers and thunderstorms return to the region later today and then the unsettled pattern repeats itself late Wednesday night into Thursday

6-Day Forecast

Today

Becoming mostly cloudy, warm, more humid, showers and thunderstorms likely this afternoon and some of the storms can be on the strong side, highs near 85 degrees

Tonight

Mostly cloudy skies this evening with more showers and thunderstorms possible, partly cloudy after midnight, lows by morning only dropping to the mid 60’s

Wednesday

Partly sunny, warm, perhaps a bit less humid, mid-to-upper 80’s

Wednesday Night

Mostly cloudy, mild, showers and thunderstorms late, some of the rain will be heavy at times, mid 60’s

Thursday

Mostly cloudy, not as warm, showers and thunderstorms continue and some of the rainfall will be heavy at times, near 80

Friday

Partly sunny, comfortable, near 80

Saturday

Mostly sunny, warm, low 80’s

Sunday

Partly sunny, warm, maybe a shower late, low-to-mid 80's

Discussion

Two excellent shots at showers and thunderstorms around here over the next few days with the first chance coming this afternoon and evening and then the second opportunity will be from late Wednesday night into the day on Thursday. Low pressure will slide to our north today and it will push a cold front into the region. Ahead of the front, more humid air will flow into the area riding in on light southwesterly winds and this influx of moisture will help to set the stage for some afternoon and evening showers and thunderstorms. Some of the storms that form late today can be on the strong side with brief heavy rainfall and gusty winds. Weak high pressure will take over on Wednesday, but then the unsettled pattern will repeat itself late Wednesday night into Thursday with more showers and thunderstorms. This second round of rain will contain some heavy downpours and possible strong-to-severe thunderstorms. Nicer weather follows to close out the work week and perhaps it will last right through the upcoming weekend.

Video

httpv://youtu.be/UVlrTNjIrRM

7:00 AM | Shower/thunderstorm threat returns on Tuesday and some of the storms can be strong

6-Day Forecast

Today

Mostly sunny, warm, highs in the low 80’s

Tonight

Partly cloudy, mild, lows by morning in the low-to-mid 60’s

Tuesday

Partly sunny, warm, more humid, showers and thunderstorms likely and some of the storms can be strong, low-to-mid 80’s

Tuesday Night

Mostly cloudy, mild, chance for more showers and thunderstorms and some of the storms can be strong, mid 60’s

Wednesday

Partly sunny, warm, slight chance for showers and thunderstorms, upper 80’s

Thursday

Mostly cloudy, not as warm, showers and thunderstorms likely and some of the storms can be strong, low 80’s

Friday

Partly sunny, warm, maybe a shower or thunderstorm, low 80’s

Saturday

Mostly sunny, warm, mid 80’s

Discussion

After a comfortable weekend in the Mid-Atlantic region, it’ll stay quite nice today as we begin the new work week, but higher humidity air will move into the area on Tuesday. Low pressure will slide to our north on Tuesday and its associated cold frontal system will approach the region from the west. As a result, showers and thunderstorms are likely Tuesday afternoon and evening and some of the storms that form later tomorrow can be on the strong side. Weak high pressure will fill in on Wednesday with partial sunshine, but then another front will affect our weather on Thursday with showers and thunderstorms again likely and, once again, some of those late week storms can be on the strong side. Elsewhere, the Atlantic Basin hurricane season has now officially begun and there are some signs for potential tropical activity in the Gulf of Mexico region by the end of this week or early next week.

Video

httpv://youtu.be/IF9CG40UuVc

7:00 AM | Weekend looks very nice; turns warmer on Monday and then the threat for showers and thunderstorms returns

6-Day Forecast

Today

Cloudy, damp and cool this morning with a touch of drizzle possible then considerable cloudiness this afternoon and not as cool as yesterday, highs in the low 70’s

Tonight

Partly cloudy skies, cool, lows by morning in the mid-to-upper 50’s

Saturday

Mostly sunny, pleasantly warm, upper 70’s

Saturday Night

Partly cloudy, cool, mid 50’s

Sunday

Mostly sunny, comfortable, upper 70’s

Monday

Mostly sunny, slightly warmer, low 80’s

Tuesday

Partly sunny, warm, good chance for showers and thunderstorm, mid-to-upper 80’s

Wednesday

Partly sunny, warm, good chance for showers and thunderstorm, mid 80’s

Discussion

After a cloudy, cool and damp start today, the afternoon will turn out warmer than yesterday despite lingering cloudiness. High pressure will build into the region tonight and Saturday ensuring another nice weekend around here with comfortable temperatures and humidity levels. It’ll turn slightly warmer on Monday with temperatures climbing into the 80’s in many I-95 corridor locations and then a frontal system will enhance the chance for showers and thunderstorms by Tuesday.

Video

httpv://youtu.be/FaFqYjTE3R4

7:00 AM | Big drop in temperatures today thanks to clouds and an ocean flow of air; occasional rain today and some of it can be heavy at times; weekend looking nice

6-Day Forecast

Today

Much cooler today with cloudy skies, occasional rain and some of it can fall heavily at times, highs only reaching the low 60’s

Tonight

More rain or drizzle this evening; otherwise, mostly cloudy skies, cool, lows by morning in the mid 50’s

Friday

Mostly cloudy, not as cool in the afternoon, drizzle possible early and then a slight chance for an afternoon shower or thunderstorm, mid 70’s

Friday Night

Partly cloudy, mild, upper 50's

Saturday

Becoming mostly sunny, pleasant, mid-to-upper 70’s

Sunday

Mostly sunny, comfortably warm, upper 70’s

Monday

Mostly sunny, warmer, low-to-mid 80’s

Tuesday

Partly sunny, quite warm, chance for showers and thunderstorm, mid 80’s

Discussion

A backdoor cold front slipped through the region yesterday and an ocean flow of air has become well-established with low-level E-NE winds. The combination of the cooler ocean air and copious amounts of clouds will keep temperatures way down today compared to normal for this time of year in what will likely turn out to be the coolest day of the week. There will be occasional rain today and tonight to go along with those cooler-than-normal temperatures and some of the rain can be heavy at times. Tomorrow promises to be somewhat warmer by afternoon with temperatures climbing back into the 70's after a cool, damp start to the day. The timing might just be perfect for another very nice weekend in the Mid-Atlantic region as high pressure looks like it will build into the area at the right time generating plenty of sunshine and comfortable temperatures and humidity levels.

7:00 AM | Showers/storms continue to threaten the region today and some of the storms that form can reach severe limits; much cooler on Thursday as an ocean flow of air gets established

6-Day Forecast

Today

Still quite warm today with mostly cloudy skies, the threat for showers and thunderstorms continues and some of the storms that form can reach severe limits, highs not far from 85 degrees

Tonight

Scattered showers this evening, maybe a thunderstorm; otherwise, mostly cloudy skies, turning noticeably cooler late, lows by morning in the mid-to-upper 50’s

Thursday

Mostly cloudy, quite cool with occasional light rain or drizzle, light NE winds, mid-to-upper 60’s

Thursday Night

Mostly cloudy, evening showers likely, cool, mid 50’s

Friday

Partly sunny, not as cool, chance for an afternoon shower or thunderstorm; especially, across northern suburbs, mid-to-upper 70’s

Saturday

Mostly sunny, comfortable, mid-to-upper 70’s

Sunday

Mostly sunny, pleasantly warm, near 80

Monday

Mostly sunny, warmer, low-to-mid 80’s

Discussion

A backdoor cold front is headed our way from New England today and this system will act to regenerate showers and thunderstorms in the Mid-Atlantic region between DC and Philly. These showers and thunderstorms can strike at just about anytime during the day and some of the storms that form later today can once again reach strong-to-severe levels. Once the cool front passes through the region, our low-level wind flow will shift to an east or northeast direction bringing into the area much cooler ocean air. Winds have already shifted to an easterly direction in the New York City region and temperatures there today will not rise past the low-to-mid 60's. Thursday promises to be the coolest day of the week around here with high temperatures confined to the 60's along with a persistent low-level NE flow of air. Along with the noticeably cooler conditions on Thursday, clouds will dominate and light rain or drizzle is quite likely to fall in the region between DC and Philly. Friday will continue to be somewhat unsettled with the chance for an afternoon shower or thunderstorm along with slightly warmer temperatures. Looking ahead, high pressure could very well generate another very nice weekend in the Mid-Atlantic region with the return of sunshine and rather pleasant temperatures and humidity levels. It’ll likely turn much warmer again early next week.

Video

httpv://youtu.be/ZhyQbPQnzP8

1:55 PM | **Here we go again...strong storms firing up and headed towards the big cities**

[Latest NEXRAD radar image; courtesy AOS-Wisconsin]

Discussion

A backdoor cold front is headed our way from New England and this will cause some big changes in the temperature department as we progress through the rest of the week. Much cooler air will move into the I-95 corridor over the next couple of days and the transition from today’s warmth and humidity to an ocean flow of noticeably cooler air will be accompanied by showers and thunderstorms. In fact, strong thunderstorms are now starting to fire up in higher terrain locations from southern New York to West Virginia and these storms are racing south and east right towards the Philly, DC and New York City metro regions and will likely reach in the time period between 3 and 9pm. There is no "severe thunderstorm watch" yet issued by the National Weather Service for the I-95 corridor, but I would expect that to develop as we progress through the mid-afternoon hours. Any storm that reaches the big cities later today and early tonight can include some heavy rainfall, damaging wind gusts, frequent lightning and, yes, possibly even some large hail. It’ll remain on the unsettled side tomorrow despite cooler conditions with showers and thunderstorms still a threat for much of the Mid-Atlantic region. Thursday is likely to turn out to be the coolest day of the week with a well-established ocean flow of cool air by then (i.e. E-NE low-level winds) and lots of clouds are likely across the Philly and DC metro regions (New York City may have more in the way of sunshine). Occasional showers are likely on Thursday south of the PA/MD border across the DC metro and Delmarva Peninsula regions and these showers could even extend as far north as southeastern Pennsylvania.

7:00 AM | The threat for strong storms later today; much cooler tomorrow and Thursday

6-Day Forecast

Today

Partly sunny, quite warm, more humid than yesterday, showers and thunderstorms likely later this afternoon and some of the rainfall can be heavy, highs in the mid-to-upper 80’s

Tonight

Scattered showers and thunderstorms this evening and some of the rainfall can be heavy; otherwise, mostly cloudy skies, mild, lows by morning in the mid 60’s

Wednesday

Cooler with mostly cloudy skies, still the chance for showers and thunderstorms, upper 70’s

Wednesday Night

Mostly cloudy, chance for evening showers, maybe a thunderstorm, cooler late, mid-to-upper 50’s

Thursday

Mostly cloudy, quite cool, occasional showers are likely, upper 60's

Friday

Partly sunny, more comfortable, chance for showers and thunderstorms, mid-to-upper 70’s

Saturday

Mostly sunny, pleasant, mid-to-upper 70’s

Sunday

Mostly sunny, comfortably warm, upper 70’s

Discussion

A cold front will approach our region today from the north and it should set off some shower and thunderstorm activity in the I-95 corridor later this afternoon into the early evening hours. Some of the storms that form later today and early tonight can be on the strong side with heavy rainfall, gusty winds, frequent lightning and possible hail. The front passes through the region early tomorrow and temperatures will respond by turning noticeably cooler on Wednesday afternoon as compared with yesterday and today with highs well up in the 80's. High pressure will tend to extend southward from eastern Canada later this week and it will have an influence on our weather by generating a cool ocean flow of air (ie E-NE low-level winds). This ocean flow will help to confine high temperatures on Thursday to the 60's in the region and there will likely be low clouds and occasional showers. Another cold front is likely to arrive by the weekend with high pressure to follow for Saturday and Sunday.

Video

httpv://youtu.be/Rp4H8qiyhhg

11:40 AM | Meteor shower after midnight and it could be quite good

[Comet 209P/LINEAR is still quite faint, but it was captured recently in this time exposure photograph]

Discussion

The Earth will pass through a stream of debris this weekend from a comet known officially as “209P/LINEAR”. This encounter could produce an outburst of bright meteors numbering more than 200 per hour if some forecast models are correct. The best time to look for these “May Camelopardalids” is between 2 and 4am early tomorrow morning. Earth won't be the only body passing through the debris zone. The Moon will also be encountering this debris field and meteoroids hitting the lunar surface may actually produce explosions that are visible through backyard telescopes on Earth.

There is much uncertainty about the strength of this meteor shower, however, both on Earth and on the Moon. As far as we know, our planet has never passed directly through a debris stream from Comet 209P/LINEAR, so no one knows exactly how much comet dust lies ahead. A magnificent meteor shower could erupt, with streaks of light in terrestrial skies and sparkling explosions on the Moon--or it could be a complete dud.

This comet is rapidly approaching Earth with its closest approach arriving on May 28th-29th. Hopefully, it will be bright enough to view in telescopes within just a few days. Comet 209P/LINEAR was discovered in February 2004 and unlike long-period comets like Hale-Bopp or ISON, it will be a frequent visitor as it swings around the sun every 5 years or so. Fortunately, the moon should not be much of an obstruction for viewing this week (waning crescent) and next when 209P/LINEAR is closest and brightest.

7:00 AM | Long holiday weekend looking pretty decent

6-Day Forecast

Today

Mostly sunny, breezy and cooler than yesterday, chance for an afternoon shower or thunderstorm, highs in the mid 70’s

Tonight

Chance for a shower early then becoming partly cloudy late, cool, lows by morning in the low 50’s

Saturday

Partly-to-mostly sunny, mild, chance for an afternoon shower or thunderstorm, mid 70's

Saturday Night

Mostly clear, cool, low-to-mid 50’s

Sunday

Mostly sunny, pleasantly warm, near 80

Monday

Mostly sunny early, some clouds late, warmer, low-to-mid 80’s

Tuesday

Mostly cloudy, warm, showers and thunderstorms likely late, mid 80’s

Wednesday

Partly sunny, warm, chance for showers and thunderstorms, low 80’s

Discussion

An upper level trough currently situated over the Great Lakes will drop southeastward towards our area today and this will keep the atmosphere on the unstable side allowing for the possibility of showers and thunderstorms to form later today. There will be a tendency for the instability in the atmosphere to diminish as we progress through the long weekend, but another shower or thunderstorm cannot be ruled out for Saturday afternoon in the Mid-Atlantic region; especially, north of the PA/MD border. By Sunday, high pressure will take control along the east coast and it should turn a bit warmer in the region. By Monday, that same high pressure will shift off the east coast and the flow on its backside will promote a warming trend and high temperatures in much of the I-95 corridor between DC and NYC will approach or surpass the 80 degree mark on Monday and Tuesday.

Video

httpv://youtu.be/Y5EfiaCkymQ