Vencore Weather
21Nov/14Fri

12:15 PM | Cold and snow threat for Thanksgiving time period

Sfc_map_Thurs
[Surface forecast map for Thursday morning by the 12Z GFS-parallel model; map courtesy tropicaltidbits.com]

Discussion

Overview
Yes, a significant warm up is about to take place in the Mid-Atlantic region; however, it will be short-lived and colder air will return to the area by the middle of next week. In addition, there are reasons to believe that a storm may organize near the Mid-Atlantic coastline during the middle-to-latter part of next week at the same time colder air is becoming more and more established in the region.

The warm up
Temperatures will climb into the 50’s on Sunday in the I-95 corridor and then peak on Monday well up in the 60’s with an outside shot at a record-breaking 70 degrees in some isolated spots. A cold front will pass through the region by Tuesday and that frontal passage will begin a downward trend in the overall temperature pattern. High temperatures around here should drop to the 50’s on Tuesday and then the 40’s on Wednesday. Once this cold front moves off the east coast early next week, it’ll tend to stall out in a north-to-south orientation and this boundary zone may then play a pivotal role in the weather pattern later next week.

Cold and snow threat
By the middle of next week, colder air will become better established in the Mid-Atlantic region and abundant moisture will become aligned with the stalled-out frontal boundary zone just off the east coast. One upper-level short wave will ride up the east coast in the Wednesday time frame, but then a second wave will follow close behind. It is this second upper-level short-wave (bigger circled area on 500 millibar height forecast map below) that will become the crucial player later next week. This critical second upper-level feature will tend to hang back behind the first wave and could generate low pressure near the coastline after the cold air becomes well-established. The 12Z GFS-parallel surface forecast map (above) features one surface low pressure system near the coastline by next Thursday morning and also an important second system over the Ohio Valley which is associated with the second upper-level feature. Depending on the timing of the interaction between this second wave and all that moisture sitting along the coastline, the result could be some snowfall in the I-95 corridor later next week. Not all computer forecast models are in agreement with this threat and we'll see how things evolve over the next few days. The forecast maps in this posting come from today's 12Z updated GFS computer forecast model (called "GFS-parallel") and the latest 12Z European forecast model also contains a snow threat for later next week. Stay tuned.

500 mb anomalies_Thurs
[500 millibar height forecast map for Thursday morning by the 12Z GFS-parallel model; map courtesy tropicaltidbits.com]

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21Nov/14Fri

7:00 AM | Colder today, but significant (albeit temporary) warm up begins on Sunday and peaks on Monday

6-Day Forecast

Today

Mostly sunny, breezy, colder than yesterday, highs in the mid 30’s

Tonight

Mostly clear, calm, quite cold, lows near 20 degrees

Saturday

Mostly sunny, cold, low-to-mid 40’s

Saturday Night

Mostly cloudy, not as cold as recent nights, low 30’s

Sunday

Mostly cloudy, noticeably milder, periods of rain developing during the afternoon hours and continuing at night, low-to-mid 50’s

Monday

Partly sunny, very mild, an occasional shower possible, but much of the time will be rain-free, upper 60’s

Tuesday

Partly sunny, breezy, cooler, mid-to-upper 50’s

Wednesday

Mostly cloudy, colder, chance for some rain or snow, mid-to-upper 40’s

Discussion

A reinforcing shot of Arctic air moved in overnight and high temperatures this afternoon will be confined to the 30’s and there will be a noticeable wind chill. Winds calm down tonight and Saturday will be a tranquil day with plenty of sunshine, but still on the cold side. A significant warm up begins on Sunday and then peaks on Monday, but it will be accompanied by some more rainfall. The 50's are likely for highs on Sunday, 60's on Monday and perhaps even a flirt with the 70 degree mark and a record-breaker, and then we'll drop back to the 50's for Tuesday. Rain is likely later Sunday and Sunday night along with the warmer conditions and a few lingering showers are possible on Monday; especially, early in the day. Even colder air pushes in by the middle of next week in time for the Thanksgiving Day holiday and we'll have to watch an area of moisture that will likely ride up along the coast at mid-week as it could back in far enough to the west to produce some problems here around Wednesday.

Video

Filed under: WMA Comments Off
21Nov/14Fri

7:00 AM | Colder today, but significant (albeit temporary) warm up begins on Sunday and peaks on Monday

6-Day Forecast

Today

Mostly sunny, breezy, colder than yesterday, highs in the mid-to-upper 30’s

Tonight

Mostly clear, winds diminish, quite cold, lows in the mid 20’s

Saturday

Mostly sunny, cold, low 40’s

Saturday Night

Mostly cloudy, chilly, cannot rule out a shower, mid 30’s

Sunday

Becoming mostly cloudy, noticeably milder, periods of rain at night, low-to-mid 50’s

Monday

Mostly cloudy, quite mild, occasional showers, mid-to-upper 60’s

Tuesday

Partly sunny, breezy, cooler, mid 50’s

Wednesday

Mostly cloudy, colder, chance for some rain or snow, upper 40’s

Discussion

A reinforcing shot of Arctic air moved in overnight and high temperatures this afternoon will be confined to the 30’s and there will be a noticeable wind chill. Winds calm down tonight and Saturday will be a tranquil day with plenty of sunshine, but still on the cold side. A significant warm up begins on Sunday and then peaks on Monday, but it will be accompanied by some more rainfall. The 50's are likely for highs on Sunday, 60's on Monday and perhaps even a flirt with the 70 degree mark and a record-breaker, and then we'll drop back to the 50's for Tuesday. Periods of rain are likely on Sunday night along with the warmer conditions and lingering showers are likely on Monday. Even colder air pushes in by the middle of next week in time for the Thanksgiving Day holiday and we'll have to watch an area of moisture that will likely ride up along the coast at mid-week as it could back in far enough to the west to produce some problems here around Wednesday.

Video

Filed under: NYC Comments Off
21Nov/14Fri

7:00 AM | Colder today, but significant (albeit temporary) warm up begins on Sunday and peaks on Monday

6-Day Forecast

Today

Mostly sunny, breezy, colder than yesterday, highs in the mid 30’s

Tonight

Mostly clear, calm, quite cold, lows near 20 degrees

Saturday

Mostly sunny, cold, near 40 degrees

Saturday Night

Mostly cloudy, not as cold as recent nights, low 30’s

Sunday

Mostly cloudy, noticeably milder, periods of rain late in the day and at night, low-to-mid 50’s

Monday

Mostly cloudy, quite mild, an occasional shower possible; especially, early in the day, but much of the time will be rain-free, mid-to-upper 60’s

Tuesday

Partly sunny, breezy, cooler, low-to-mid 50’s

Wednesday

Mostly cloudy, colder, chance for some rain or snow, low-to-mid 40’s

Discussion

A reinforcing shot of Arctic air moved in overnight and high temperatures this afternoon will be confined to the 30’s and there will be a noticeable wind chill. Winds calm down tonight and Saturday will be a tranquil day with plenty of sunshine, but still on the cold side. A significant warm up begins on Sunday and then peaks on Monday, but it will be accompanied by some more rainfall. The 50's are likely for highs on Sunday, 60's on Monday and perhaps even a flirt with the 70 degree mark and a record-breaker, and then we'll drop back to the 50's for Tuesday. Rain is likely late Sunday and Sunday night along with the warmer conditions and lingering showers are possible on Monday; especially, early in the day, but there will be rain-free time as well. Even colder air pushes in by the middle of next week in time for the Thanksgiving Day holiday and we'll have to watch an area of moisture that will likely ride up along the coast at mid-week as it could back in far enough to the west to produce some problems here around Wednesday.

Video

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