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STORMcast Discussion 2022-03
Time: 0615 EST
Good morning everybody. As the morning models roll in for the path of Nicole's remnants, I thought I'd put out a quick Discussion on what we can expect in the Philly region as it cruises by overnight tonight.
In general, I do not think this will be a big deal other than the fact we're experiencing it in November which is pretty unusual. As the storm tracks northward (its center is currently near Atlanta), two main things will happen. First, the low will come in contact with a trough currently over the Midwest that will scoop it up and begin to steer it on a more northeasterly track taking what used to be the eye over central PA around 1 AM Saturday. Second, the storm will make a structural transition from a tropical to an extratropical cyclone which will have some impact on our own weather tonight.
Severe Weather Threat
The alert map at right shows the northern edge of a large Tornado Watch posted for much of VA and the Carolinas (the yellow boxes). Although this threat exists today, by the time the remnants of Nicole reaches our area and becomes consumed by the incoming trough, this threat should diminish considerably. However, with a very warm air mass injected by Nicole, its associated instability, and a strong cold front approaching from the west, there's still room for a burst of isolated strong to severe weather during the overnight hours. The threat should be short-lived and peak during the predawn hours but it cannot be ruled out entirely. If this risk increases, we might see the Tornado Watch gradually marched further north but, at least for now, I do not see this affecting the Philly region. Pay attention to the NWS for this development if it occurs at all.
Honestly, the precipitation estimates are not all that impressive with the focus of the rainfall being more focused near the center of circulation to our west. 1" to 2" seems reasonable at this point with localized street flooding possible due to all the leaves on the ground but I do not expect a widespread flooding threat. The transition of this storm into an extratropical cyclone also means that, instead of coming as a big blob of precipitation, we'll actually get two bursts of rain with what might be a sizable gap in between. The first shot will likely occur Friday afternoon from around lunchtime until around dinner. This is basically an outer rain band from the original tropical system. It will come with some downpours, wind and unusually warm temperatures for November.
NWS advisory map as of STORMcast issuance time.
(Map courtesy of the NWS)
HAZARDOUS WEATHER OUTLOOK - Entire forecast area for the possibility of isolated severe weather potential associated with Nicole remnants overnight Friday.
WIND ADVISORY - Coastal NJ from 11 PM to 9 AM Saturday. 20-30 mph sustained wiwinds with higher gusts expected.