DAYS 1-5 (NOVEMBER 30 – DECEMBER 4)
On this final day of November our main focus will be a storm system that will impact the region today, as well as into the first couple days of December, albeit much less so after this evening. The evolution of this system began over the weekend as a jet stream trough made its way eastward across the US. Surface low pressure developing near the western Gulf Coast region and has made its way northeastward as of this morning to a point it is about to move northeastward out of the Tennessee Valley then up the Appalachians and into the St. Lawrence Valley via New York State. The upper level system driving it is becoming a closed off low pressure area and as the surface storm maxes out while passing west of New England, a strong pressure gradient between it and offshore high pressure will result in a strengthening southerly wind flow across our area today. Also a significant ribbon of moisture will produce a significant bout of rainfall in the form of steady moderate to heavy rain ahead of a warm front then widespread moderate to heavy rain showers and embedded thunderstorms in the warm sector after the warm frontal passage and ahead of the cold front from midday through late evening. It is in the warm sector with the convective rainfall that the both the strongest gradient wind and strongest wind gusts will occur. If you have outdoor decorations, make sure they are secured as strong wind gusts could disturb them greatly. With trees mainly leafless, the chance of tree damage has dropped off, but some older, weakened trees may still come down or lose limbs, and this can result in some property damage and/or power outages. Street and parking lot flooding will be an issue due to heavy rain, and exacerbated where any leaves block storm drains. Coastal flooding will not be a significant issue as the tide should be shy of reaching its high for the night while the strongest winds occur, and this particular tide is not nearly as high as the series with saw with the new moon a couple of weeks ago. Once the axis of moisture gets beyond our region, the clouds will break and the air will remain quite mild overnight into Tuesday, but being on the eastern side of a closed low pressure area keeps us in the risk area for additional rain showers, although these should be just scattered. So December will start off feeling a bit more like a day in mid spring. As the upper low lifts its way into and through eastern Canada, our winds turn more westerly here Wednesday and Thursday, driving drier and seasonably chilly air into our area. By Friday, the next low pressure trough will be moving in from the west rather quickly (a little more quickly than previously anticipated) so the weather will be unsettled, mild enough for rain, but not nearly as stormy as the system we will see later today.
TODAY: Overcast. Rain arriving late morning through midday southwest to northeast, may be heavy at times during the afternoon. Highs 57-64 occurring late-day. Wind SE to S increasing to 10-20 MPH except 20-30 MPH coastal areas with higher gusts all areas by late in the day.
TONIGHT: Overcast evening with widespread rain showers and a chance of thunderstorms. Breaking clouds overnight with a chance of additional isolated to scattered rain showers. Lows 45-52. Wind S 15-35 MPH with gusts as high as 45-60 MPH evening (gusts above 60 MPH may occur in isolated coastal locations and higher elevations), shifting to SW 10-20 MPH with gusts 30-40 MPH overnight.
TUESDAY: Variably cloudy. Chance of rain showers. Highs 57-64 occurring in the morning, then falling through 50s by late-day. Wind SW to S 10-20 MPH with higher gusts.
TUESDAY NIGHT: Variably cloudy with a chance of rain showers evening. Partly cloudy overnight. Lows 33-40. Wind SW 5-15 MPH, higher gusts.
WEDNESDAY: Sun/cloud mix. Highs 42-49. Wind SW to W 10-20 MPH.
WEDNESDAY NIGHT: Mostly clear. Lows 28-35. Wind W 5-15 MPH.
THURSDAY: Mostly sunny. Highs 39-46. Wind W 5-15 MPH.
THURSDAY NIGHT: Increasing clouds. Lows 31-38 occurring in the evening. Temperatures may rise overnight. Wind W up to 10 MPH shifting to SW.
FRIDAY: Mostly cloudy. Chance of rain showers. Highs 45-52. Wind SW 5-15 MPH shifting to W.
DAYS 6-10 (DECEMBER 5-9)
A lot of uncertainty in this period. Watching the computer models try to “figure this out” has been interesting. Based on what I know through Friday, my best guess is the previous “weekend storm threat” actually holds off until the December 6-7 time frame with the first part of the weekend more likely to be dry. The storm that would result from the passage of a low pressure trough has a very questionable evolution and potential track, so it will be something to watch for now and I will once again try to pin down more detail as we get closer. A period of windy/colder weather would likely follow this threat (whether the storm impacted the region or missed it), perhaps with some snow showers.
DAYS 11-15 (DECEMBER 10-14)
Continuing to watch the potential for a colder and stormier period of weather in this time frame due to less high pressure in the US Southeast and a temporary disruption of the polar jet stream with indications for a fairly large scale trough of low pressure impacting the central and eastern US, including our region. Low confidence forecast at this time.