... Surface and upper-level ridging builds across the region today into Thursday. A strong low pressure system will approach the area from the Tennessee River Valley Thursday night into Friday. High pressure is expected to return over the weekend and persist into the first half of next week.
NEAR TERM /THROUGH TONIGHT/...
Nor'easter continues to linger just off the NE coast, packing very gusty winds across areas further north. Upper ridging is beginning to be felt across a large portion of the forecast area aside from along and west of the Allegheny Mountains, leading to mostly sunny conditions. Gusty northwest winds will prevail through the rest of the morning and early afternoon before beginning to subside later this evening ahead of the next system set to cross through the area late Thursday night. Upper trough should begin to push the Nor'easter further out in the Atlantic which will help the pressure gradients for the winds to begin to subside later this afternoon.
Dry and cooler for tonight with the ridge directly overhead. Should also start out mostly clear before some clouds start to build in towards Thursday morning. Low temps in the low to mid 40s for most, but the mountains dip into the 30s.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... For the first half of Thursday, high pressure will remain the primary influence on the weather, with dry conditions expected. However, looming to our west is a very deep upper-level trough over the Plains which will form a cutoff low over the MS River by Thursday night. A very strong surface low will also be occluding underneath the upper-low during this time, with the warm front pushing northward towards our region by Thursday evening.
Timing seems to have shifted more into the Friday timeframe for the actual frontal passage. Strong onshore flow ahead of this warm front will lead to an anomalously moist airmass for late October (1.5"+ PWATs). With U-wind anomalies in the 3-4 sigma range, expect a significant enhancement of rainfall along the Blue Ridge. This looks to be a rather quick-moving band of rainfall though. Think the primary flood threat will be along the higher terrain where enhancement will be greatest. A slight risk of excessive rainfall was introduced by WPC for portions of the area as a result. As far as severe weather is concerned, just think we are too stable with a wedge in place ahead of the frontal passage.
Aside from the heavy rainfall threat will come a pretty substantial wind threat once again. Very impressive flow in the 925-850mb level (on the order of 60-65 kts). Threat would primarily be over the higher terrain though, as the stable layer should keep winds somewhat in check closer the surface in the lower elevations. Could see wind headlines being introduced in future forecast cycles. Marine winds will also be a threat, but more on that in the marine discussion below.
Temperatures on Friday stick to the low to mid 60s amidst the rain and cloud cover associated with this system. In contrast, overnight lows won't deviate much, only dropping into the upper 40s to low 50s.
LONG TERM /SATURDAY THROUGH TUESDAY/... Upper level low pressure will be crossing the area Saturday afternoon with showery weather continuing. Ridging starts building over the area Sunday with improving weather conditions although a bit breezy on Sunday. High pressure builds at the sfc for next week supporting fair weather and seasonable temperatures.