textproduct: Columbia

WHAT HAS CHANGED

Updated Key Message 1 with current conditions. Aviation discussion updated for 00z TAF.

KEY MESSAGES

- 1. Generally low chances of rain through Friday, favoring the CSRA with a warming trend expected across the area.

- 2. Increased chances of rain over the weekend with highest chances on Sunday into Monday.

DISCUSSION

Key Message 1: Generally low chances of rain through Friday, favoring the CSRA with a warming trend expected across the area.

Showers and thunderstorms continue to diminish this evening as temperatures are decreasing. A couple of outflow boundaries are noted on radar imagery, but they haven't had much luck generating any new activity. The rest of the night should be fairly quiet with skies clearing and temperatures falling into the mid 70s. Similar expectations for tomorrow regarding convection and the potential for some heavier downpours given high PWATs and slow storm motions. Coverage will likely be confined to the CSRA and may be even less as some of the drier air to our north works southward.

Temperatures will be warming on Thursday and Friday as the upper ridge axis shifts southeastward from the upper Midwest to the Carolinas. NAEFS shows 850mb temperatures above the 99th percentile both days while the ECMWF also highlights anomalously high max temps to end the week. Expect high temperatures to push back into the mid and upper 90s with Friday being the warmest day. While deep mixing should result in some drier air mixing down to the surface, heat indices are expected to rise back above 100 degrees and could reach 105 by Friday.

Key Message 2: Increased chances of rain over the weekend with highest chances on Sunday into Monday.

Ensemble guidance suggests the upper ridge will retrograde and become re-established over the western CONUS by Saturday with an upper weakness left behind across the deep south and northeastern Gulf. This will allow for troughing across the OH Valley into Mid-Atlantic and New England bringing shortwave energy into the region interacting with above normal PWATs resulting in an increase in chances of convection late weekend into early next week.

There may be a slightly better chance of severe weather on Sunday as well with some increased wind shear and upper forcing from shortwave energy combining with diurnal instability. Also of note, NHC has added a 20% area across the northeastern Gulf for possible tropical development in the next 7 days.

AVIATION /00Z THURSDAY THROUGH MONDAY/

VFR conditions are expected throughout the period.

Quiet weather has really settled into the area this evening, with a few weak showers hanging around mainly the Augusta sites. These are forecast to diminish this evening as the sun sets and instability settles into the area. Clear skies are expected tonight, with restrictions not expected. AGS/OGB may be the exception as this is a setup that tends towards some IFR ground fog, so have a TEMPO in for that. Beyond that, the period should feature VFR conditions. Winds will generally be light out of the west or southwest.

EXTENDED AVIATION OUTLOOK...The threat for restrictions eases for the end of the week into the upcoming weekend as conditions begin to dry out. Restrictions from showers and thunderstorms return this weekend.

CAE WATCHES/WARNINGS/ADVISORIES

SC...None. GA...None.