textproduct: Columbia

WHAT HAS CHANGED

Aviation discussion updated for 18z TAF. No major adjustments made to Key Message 1 & 2.

KEY MESSAGES

- 1) Dry weather conditions continue today with slightly elevated Fire Weather concerns.

- 2) Beneficial rainfall still appears likely late Saturday night through Monday. Guidance remains consistent with a general 0.5"-1.0" across the area, and the potential for higher totals across the northern Midlands.

DISCUSSION

KEY MESSAGE #1: Dry weather conditions continue today with slightly elevated Fire Weather concerns.

A very dry airmass is expected to remain in place across the area today. Ran with a blend of the NBM10 and HRRR to account for dewpoints that were way lower than the forecast starting point earlier. As such, forecast minimum relative humidities in the 20% to 25% range can be expected this afternoon, though some spots could see values falling into the teens if we dry out even further than anticipated. Generally light winds will keep fire danger to a minimum, but appropriate precautions should be taken if burning today. Modest moisture recovery is then expected to begin Saturday night into Sunday ahead of the next system. At this point, PWAT values should increase, reaching 0.5"-0.75" by Sunday morning, with dewpoints following suit and reaching the 40s around the same time.

KEY MESSAGE #2: Beneficial rainfall still appears likely late Saturday night through Monday. Guidance remains consistent with a general 0.5"-1.0" across the area, and the potential for higher totals across the northern Midlands.

The forecast remains on track for our soaking rainfall on Sunday. Guidance is in good agreement in timing and location of the mid-level low, ejecting from the Baja region today and tomorrow, and the associated surface low. Overall, guidance is slightly slower with the progression of all of this but that really doesn't impact the overall forecast. LREF clusters are in good agreement that 0.5-1.0" of rainfall is expected with this system. The highest totals are likely to be in the northern Midlands, generally north of I-20, where the warm front lifts to and adds a bit of extra forcing/focus for rainfall on Sunday evening. Some thunder is possible with the rain as convection to our west develops, moves eastward, and weakens over the area Sunday evening. These heavier rain showers could enhance overall precip rates and allow other areas to approach the 1" mark. But overall, a good expectation is around 0.5" for most, which will be nice and beneficial. By next week, a major warm up is on tap with LREF guidance suggesting 90th percentile 500 hPa heights and at least 98th percentile 850 hPa temps overspreading the area by the middle of next week.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

VFR conditions expected through the TAF period.

Dry high pressure will settle across the region throughout the afternoon and into Saturday. As a result, no notable aviation restrictions are expected through the TAF period. Winds will remain light and variable through the period as well. Mid-level clouds will steadily move in towards the end of the period, but VFR.

EXTENDED AVIATION OUTLOOK...Restrictions continue to look most likely Saturday night through Sunday with the next system moving in, bringing widespread rain chances.

CAE WATCHES/WARNINGS/ADVISORIES

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