textproduct: Raleigh

SYNOPSIS

Seasonably chilly high pressure will settle across the Southeast US through Tuesday. A trough of low pressure will approach from the northwest mid-week.

NEAR TERM /TODAY THROUGH TONIGHT/

As of 257 AM Monday...

High pressure centered over the TN Valley this morning will shift south of the region later today and tonight. Seasonably cold conditions today and tonight will begin to moderate Tuesday. Highs today generally 48-52. Lows tonight 25-30.

SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/

As of 257 AM Monday...

Moderating temperatures can be expected with the SW flow increasing. Expect sunny skies Tuesday with some increasing clouds Tuesday night out ahead of the next approaching trough from the NW. Highs moderate into the 55-60 range, with lows in the mid 30s to lower 40s.

LONG TERM /WEDNESDAY THROUGH MONDAY/

As of 400 AM Monday...

A northern stream shortwave will dive SE out of Canada into the Great Lakes on Wednesday and Wednesday night, before developing into a closed low over the OH Valley, swinging east then northeast across the Mid-Atlantic and New England on Thursday and Thursday night. Meanwhile a pair of southern stream waves will move east across the northern Gulf and FL, then northeast into the Atlantic. At the surface, low pressure will develop over the northern Mid-Atlantic on Wednesday, then deepen over New England on Thursday, dragging a cold front that crosses central NC on Wednesday night.

There is a slight chance of rain on Wednesday (mainly in the Sandhills and Coastal Plain) as the first southern stream wave passes to our east along the coast, followed by another small chance on Wednesday night with the frontal passage. But any amounts look light (around a tenth of an inch or less). The potent shortwave aloft will pass through the area on Thursday afternoon and evening in the wake of the surface low/front, but 00z runs of the GFS and ECMWF have trended drier and essentially have no precipitation with it anymore across our region, as do the vast majority of their ensemble members. So while a bit of rain or snow can't be ruled out as the cold air rushes in, chances are decreasing and the "cold air chasing the precip" setup is rarely favorable for much if any snow. So impacts if any look very limited.

Wednesday's temperatures will be 5-10 degrees above normal with SW flow ahead of the front, generally in the mid-to-upper-50s, followed by lows Wednesday night in the mid-to-upper-30s. Thursday's highs may end up occurring at midnight as CAA behind the front drops temperatures into the 30s through the day. NW post-frontal gustiness is also expected, in the 20-30 mph range. Some breeziness will continue on Thursday night, and with lows dropping into the upper- teens to lower-20s, wind chills will drop into the lower-teens and maybe even single digits in some spots.

Dry and sunny conditions will return on Friday as surface high pressure builds in from the SW. High temperatures will turn 5-10 degrees below normal, in the lower-to-mid-40s. As the high moves offshore on Friday night, temperatures won't be quite as cold but still below normal, with lows in the 20s. The next mid/upper trough will approach from the west on Saturday and move across central NC on Sunday, as a surface low moves from the Great Lakes into SE Canada, dragging another cold front that passes through central NC on Saturday night. Ahead of the front, conditions will briefly turn a bit warmer on Saturday with highs in the upper-40s to lower-50s. While the GFS is largely dry over the weekend as the best upper forcing goes to our north, the ECMWF has a sharper trough and develops a secondary surface low that tracks along the Eastern Seaboard, which would result in a threat of rain or snow on Sunday. Too much divergence in the models for anything beyond slight chance POPs at this time, but will continue to monitor. Dry and sunny conditions will return for Monday. Temperatures will turn below normal again on Sunday and Monday with highs in the 40s and lows in the upper-teens to mid-20s.

AVIATION /12Z MONDAY THROUGH FRIDAY/

As of 630 AM Monday...

VFR conditions are expected through 12z/Tuesday.

Outlook: Generally VFR conditions are expected into Thursday. A strong low pressure system will develop and deepen across and offshore the middle Atlantic region on Thursday, when a chance of showers and gusty winds with associated flight restrictions will be possible.

RAH WATCHES/WARNINGS/ADVISORIES

None.