textproduct: Blacksburg

SYNOPSIS

A wintry mix will arrive late tonight and continue into Tuesday morning. Wintry mix will turn to all rain by late Tuesday morning. Dry high pressure settles into the region for most of the week. Another potential disturbance on Friday could bring light frozen precipitation to the region.

NEAR TERM /THROUGH TUESDAY/

As of 715 PM EST Monday...

Overall no large changes to the forecast this evening. Low pressure continues to strengthen across the deep south and moisture has already begun to push into Tennessee and Georgia. Still looking at an arrival time of around midnight for the far southwest portions of the CWA, with precipitation spreading northward quickly thereafter. The 00z evening RAOB still shows some dry air aloft, and as initial precipitation evaporates into the dry airmass, should see temperatures briefly cool before warm air advection wins out over the cold. This may lead to a sleet mix at the onset across the mountains, but eventually most locations in the mountains and Foothills see just freezing rain. Still expecting just a cold rain for Southside Virginia and north central North Carolina.

As of 130 PM EST Monday...

Key Message:

1) Winter Weather Advisory expanded eastward due to Freezing Rain Hazard.

The main headline difference from the forecast earlier this morning is the Winter Weather Advisory has expanded a little eastward due to the potential for more widespread freezing rain. Surface temperatures flirting around freezing overnight in the VA Piedmont will increase the likelihood of ice. Between a trace and a tenth of an inch of ice accumulation is forecast for the added counties. Elsewhere, the forecast has not changed too much. Freezing rain is expected to be the dominant precipitation type between midnight and sunrise on Tuesday. Highest ice accumulations are likely to be between 0.10-0.20 inches but localized areas could see ice totals of a quarter inch. Snow will be concentrated along I-64 and but even in this location most of the area will only see between a trace and half an inch. Western Greenbrier may see between 1-2" of snow. By mid-Tuesday morning, most of the precipitation will have transitioned to rain and the system will out of the region by the afternoon. Some upslope snow may linger in Western Greenbrier, thus why they may receive more snowfall amounts. Total rainfall amounts are dependent on what converts to ice and snow, but places that only receive rain may have between 0.50-1.00".

Lastly, winds will start off easterly/southeasterly from the wedging of a surface high pressure system to our northeast but will become northwesterly as a surface low moves to our east and a surface high pressure system starts to approach from our west.

SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/

As of 1210 PM EST Monday...

Key Message:

1) Mainly dry with colder than normal temps.

Keeping this part of the forecast dry, though a front does push across Thursday, moisture is limited as it arrives from the west/northwest. Cloud cover could linger into Wed morning over the mountains behind departing Tuesday system. Not out of the question to have some freezing drizzle along those western slopes of WV Tuesday evening.

Highs will continue to run 5 to 15 degrees below normal while lows will be just below normal.

LONG TERM /FRIDAY THROUGH MONDAY/

As of 1217 PM EST Monday

Key Messages:

1) Trend is for less impact from next system Friday into Saturday but not totally dry.

2) Low confidence for the weekend into Monday forecast but leaning dry.

Trend in the models/ensembles is to have a stronger northern stream trough that shunts the southern stream system further south. This in turn will keep better precip chances over the southeast U.S. Still some models/ensembles have precip chances into our area, so cannot discount that. Leaned toward a blend of the models, which still looks like snow changing to rain scenario Friday, then back to snow Friday night over portions of the area. Wedge may allow for some freezing precip as well, but confidence is low on ice, based on track of the low from the Gulf Coast to off the SC/NC coast. Models keep this low weak until it gets well east of Virginia. Could see some deformation zone/upper enhanced precip into Saturday, with precip mainly changing back to rain, except some mix in the mountains.

Beyond Saturday, though another quick moving upper system/front pushes across Sunday with low chance pops.

Confidence remains low on the overall wintry setup this weekend.

EXTENDED AVIATION OUTLOOK

Return to VFR for most by Wednesday-Thursday, though the progression to become VFR will be slower at BLF. For Friday, another storm system will approach the lower Mid-Atlantic to bring wintry weather and degraded flying conditions.

RNK WATCHES/WARNINGS/ADVISORIES

VA...Winter Weather Advisory until noon EST Tuesday for VAZ007- 009>020-022>024-032>035-043>047. NC...Winter Weather Advisory until noon EST Tuesday for NCZ001>004- 018>020. WV...Winter Weather Advisory until noon EST Tuesday for WVZ042>044- 507-508.