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KEY MESSAGES

* Cold temperatures tonight will result in frost for some areas, which could result in damage to sensitive outdoor vegetation.

* Warmer weather in store for Sunday with dry and windy conditions in the afternoon.

* Well-above normal temperatures and precipitation chances return early-to-mid next week, with waves of unsettled weather likely later next week.

SHORT TERM /THROUGH TONIGHT/

Issued at 305 PM EDT Sat Mar 28 2026

As of early afternoon Saturday, RAP 500 mb model analysis and water vapor imagery showed a trough of low pressure across the Ohio Valley with a ridge of high pressure building to the southwest. Dry air in place over the area had observations as low as the upper 30s across the forecast area with steady northeast wind between 10 to 15 mph. Temperatures were in the upper 40s to lower 50s.

Strong surface high pressure associated with the upper level building ridge in the southwest will continue to shift eastward tonight into Sunday with warm air advection returning to the area. Until then with light winds, clear skies and cold air still in place, many locations tonight will see frost development. The greatest confidence in low temperatures at or below freezing for several hours would be in the Bluegrass region with greater than 50% chance via NBM data.

With southerly wind flow return, temperatures will quickly rebound into the upper 60s to low 70s. RAP soundings show plenty of dry air with dry adiabatic soundings mixing up to 800 MB, which will likely tap into wind gusts up to 25-30 mph Sunday afternoon with relative humidities in the 20s. As a result, the forecast was nudged toward the 75th percentile of NBM windspeeds. Some locations could see even drier RH values than what the NBM forecast has with the good mixing on tap. Wind gusts will diminish after sunset as the diurnal inversion returns, but some southerly wind gusts may continue as the pressure gradient across the region remains elevated. Warm air advection will keep overnight lows Sunday night into Monday morning in the 50s with very low chances (via NBM data) to drop lower than 50 degrees (5% chance).

LONG TERM /SUNDAY THROUGH SATURDAY/

Issued at 305 PM EDT Sat Mar 28 2026

Sunday, with mildly a amplified, almost zonal, upper ridge sitting over the CONUS, surface high pressure sits along the Virginia/North Carolina coast with low pressure centered over the Plains, keeping south to southwest winds blowing in the CWA. WAA lifts highs to the mid 60s to low 70s on Sunday before the low 70s to near 80 on Monday.

Monday, with the surface high sitting over the Atlantic, anti- cyclonic flow continues to carry Gulf moisture up the Mississippi and Ohio Valleys, resulting in PWAT values increasing to just over an inch on Monday. With afternoon warming, an isolated shower or two could develop, but chances are only around 10 percent. This chance of an isolated shower continues again Tuesday afternoon during the mostly sunny day as temperatures return to the low to mid 80s.

Tuesday night into Wednesday, a surface low quickly moving east through southern Quebec and drags a cold front through the CWA. With the continued funnel of moisture from the Gulf, PWATs increase slightly to 1.25-1.3" ahead of the front, and with the front becoming more west to east oriented over the Ohio Valley, it could keep showers and thunder in the area through Wednesday night. There continues to be little chance for anything severe, but widespread waves of showers are expected. The front will limit high temperatures to the low 60s over southern Indiana to the mid 70s near Clinton County on Wednesday.

Wednesday night, a shortwave moving along messy zonal flow is expected to develop a surface low near the Ozarks and quickly push it northeast through the Ohio Valley as PWATs increase to 1.5-1.6" or so, developing another surge of rain for Thursday through at least midday on Friday. Again the severe threat continues to look pretty low, but widespread showers are expected. Limited warming keeps highs in the mid 50s to mid 60s Thursday before WAA brings a return to the 70s for Friday and Saturday.

Models are starting to pick up on a longwave trough disturbance pushing through the central plains and toward the midwest late next weekend into early next week. There is disagreement on timing, but the general pattern exists similarly among medium range models. The next chance for strong thunderstorms could be in this time period, but stay tuned for more details as the forecast evolves.

AVIATION /18Z TAFS THROUGH 00Z MONDAY/

Issued at 125 PM EDT Sat Mar 28 2026

VFR for area terminals for the next 24-30 hours with a few high level clouds (mainly SKC) and east/northeasterly winds shifting to the south. Introduced wind shear to the forecast mainly for central KY terminals, although southern Indiana terminals along the Ohio River may see wind shear as well tonight from 7z into early morning tomorrow around 14z at 2K feet from the south/southwest between 30-40 kts. Wind shear diminishes after 14z as surface gusts pick up from the south up to 25 kts for tomorrow afternoon and diminishing after 00z March 30th.

LMK WATCHES/WARNINGS/ADVISORIES

KY...Frost Advisory from midnight EDT /11 PM CDT/ tonight to 10 AM EDT /9 AM CDT/ Sunday for KYZ024-025-028>036-038>041- 045>049-053>057-063>067-077-078. Freeze Warning from midnight tonight to 10 AM EDT Sunday for KYZ037-042-043. IN...Frost Advisory from midnight tonight to 10 AM EDT Sunday for INZ076>079-084-090>092.