textproduct: Blacksburg

SYNOPSIS

A low pressure system over the Tidewater of Virginia will shift north and weaken along the northeast coast by Thursday. High pressure builds in Thursday into Friday with a moisture-starved backdoor front making it into our area this weekend. A few showers are possible but not a lot is expected.

NEAR TERM /THROUGH THURSDAY/

As of 141 PM EDT Wednesday...

Key Messages:

1) A dry weather pattern tonight into Thursday.

2) May have some dense fog issues late tonight in portions of the area.

An upper low was located the Tidewater of VA this morning. It will track slowly to the north-northeast into this evening and weaken.

Main changes to the forecast were to lower pops further west and increase sunshine. Otherwise, forecast on track as should be dry for most by mid afternoon.

With rain and clearing skies/light winds dense fog looks to be a potential especially in the Piedmont and north of the Roanoke/New River Valley late tonight. Will have to monitor for an advisory.

Thursday after any fog lifts, expect mainly sunny skies and highs about 5-10 degrees warmer than today with upper 70s to lower 80s in the mountains, to mid 80s east.

SHORT TERM /THURSDAY NIGHT THROUGH SUNDAY/

As of 116 PM EDT Wednesday...

Key Messages:

1) High pressure wedging returns to the region.

2) A chance of precipitation this weekend.

Weather prior to the weekend is a bit mundane due to a surface high pressure system to our northwest in Canada and another to our east in the Atlantic and little action in between. Around this time there will be ridging to our north and troughing to our south with the Mid- Atlantic stuck dead in the middle. The weekend, however, is a little different as a cold front that precedes the Canadian high will likely pass through. The Canadian high will proceed to move east over New England and reintroduce another wedge into the mountains. The cold front will reflect this wedging as it will bend around the mountains and part of the front over the Ohio River Valley will retreat northeastward as a warm front while the cold front down in the Carolinas will stall. The weather pattern setup heavily suggests easterly winds east of the Blue Ridge and southeasterly winds along and west of the Blue Ridge as the wedging takes shape. These winds could be a bit breezy and gusting between 10-20 mph, especially on Sunday. With the front will come a small chance of precipitation for the region late Saturday into Sunday. While PWATs do climb to about 1-1.5", the high pressure wedging will put a limit on any serious convection. Otherwise, temperatures will slightly change as the front passes. Friday, before the front, will be the warmest with highs in the upper 80s east of the Blue Ridge. Post-cold front, highs will be in the 70s and lows will likely be in the lower 60s to lower 70s. Dew points will drop a little after the cold front, but will recover to as high as the mid-60s due to the easterly winds.

LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/

As of 117 PM EDT Wednesday...

Key Message:

1) Cutoff low moves in the Great Plains next week.

Wedging will deteriorate as the surface high pressure system over New England moves further east and into the Atlantic early next week. An upper level low pressure system from western Canada moves southeast into the Great Plains and becomes cutoff from the main zonal flow. This cutoff low stays relatively stationary for the duration of the forecast period. It's specific location will heavily determine the weather pattern for the area for next week so it is currently difficult to state for certain what can be expected. Recent model guidance suggests the cutoff low will be too far west to affect the Mid-Atlantic which would result in a relatively quiet weather pattern. PWATs are forecast to continue to climb to the 1.25- 1.75" range which would be around the 90th percentile climatologically speaking. So, if this cutoff low were to move east and bring precipitation chances to the area, heavy rain would be a concern. This system will be monitored in future forecasts.

Also, Tropical Storm Gabrielle has formed in the Atlantic and is currently not expected to affect the area or make landfall over the United States.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/

As of 150 PM EDT Wednesday...

VFR conditions expected through 18z Thursday for most. But there will be a window from 06-13z where fog will form and could drop vsbys to IFR or lower over most of the area. Highest confidence is LWB/BCB/LYH with moderate confidence of at least MVFR at ROA/DAN/BLF.

EXTENDED AVIATION FORECAST...

Should maintain VFR into the weekend aside from any late night fog normally at LWB/BCB. A front this weekend looks limited on moisture so am anticipating VFR. Potential sub-VFR early next week as high pressure wedges down while warm lifts back north.

RNK WATCHES/WARNINGS/ADVISORIES

VA...None. NC...None. WV...None.