textproduct: Jackson

KEY MESSAGES

- Today will be colder than normal in the wake of a cold front. There will be some light snow showers or flurries across northern portions of the area as the precipitation tapers off this morning. - Periodic rain chances are forecast from Monday night to Thursday, with temperatures trending to about 15 degrees above normal for Christmas.

- Overall, a minimum in rain chances is forecast for Christmas.

UPDATE

Issued at 620 AM EST FRI DEC 19 2025

No significant changes were made to the forecast with mainly just the inclusion of the latest obs and trends for the T/Td/Sky grids. Also, did a fine tuning of the PoPs for the cold front crossing the eastern part of the area this morning bringing a transition to a touch of snow. These adjustments have been sent to the NDFD and web servers along with a freshening of the zones and SAFs.

LONG TERM

(Saturday night through Thursday) Issued at 437 AM EST FRI DEC 19 2025

The period is expected to begin with an upper level low in Ontario to the north of Lake Superior with a trough south into the Upper and Middle MS Valley as well as western Great Lakes. Over the western Conus to Plains, west to west northwest flow is anticipated. At the surface, an area of low pressure is expected to be centered in Ontario with a cold front trailing into the Central Great Lakes to Lower OH Valley region with sfc high pressure south of eastern KY extending from east of the VA and Carolina coast to the Gulf while another sfc high is expected to be centered over the Central Plains. A secondary boundary is expected to extend from the low in Ontario to near the NE and SD border and then northwest into parts of MT and Alberta with another sfc high behind it centered in Saskatchewan extending into the Dakotas.

Saturday night to Sunday night, the upper low/trough in Canada will move into Ontario and then the Maritimes Crossing the Great Lakes, portions of the OH Valley, mid Atlantic, and Northeast. The sfc low should precede the upper low across eastern Canada with the first cold front crossing eastern KY Saturday night, followed by the secondary boundary on Sunday. Shortwave upper level ridging will move across portions the Rockies and into the Plains/central Conus to the Great Lakes to Lower OH Valley during this time. The associated sfc high will build southeast from Saskatchewan across the Northern Plains and Upper MS Valley to the Great Lakes and OH Valley and is progged to strengthen. The first cold front is expected to have some limited low level moisture with it with some upper level moisture with the associated trough the secondary boundary will be even more moisture starved and no precipitation is expected with either. However, a colder and a bit drier airmass is expected to arrive for Sunday behind the secondary boundary.

Highs on Sunday should be a couple of degrees below normal. The sfc pattern should set the stage for valleys to decouple Sunday night, especially those in the east and southeast, with a moderate ridge/valley split anticipated. Some of the colder spots are forecast to reach near 20 or the upper teens. Adjustments were made from the NBM min T for Sunday night to close to the Coop MOS numbers for these valley areas and to better fit the anticipated pattern.

Early Monday, the pattern will be rather zonal across the Conus downstream of an upper level trough nearing the west coast of the Conus initially with rather low amplitude upper ridging extending from Mexico into the High Plains/Plains. Shortwave upper ridging is expected to move east of the Commonwealth on Monday with a shortwave trough of two moving from the Central Conus to the Lower OH Valley Valley. These shortwaves are expected to progress across the Commonwealth Monday night to early Tuesday while a stronger shortwave is expected to track from BC/Northern Rockies near the US/Canadian border reaching western Ontario to the Upper MS Valley by early Tuesday with an associated sfc low also reaching western Ontario with the associated cold front trialing into the Upper MS Valley/SD to western Conus. Then from Tuesday to Tuesday night, the pattern is progged to amplify with upper ridging becoming centered over TX to the western Gulf/Lower MS Valley and also building north through the Plains/Central Conus and the TN Valley with this all occurring downstream of troughing in the eastern Pacific to west coast of the Conus. Over the Commonwealth/eastern KY region, shortwaves moving around this developing ridging are expected to cross the region while the shortwave over western Ontario to the Upper MS Valley rather quickly moves across Ontario and Quebec as well as the Great Lakes and Northeast and nears the Maritimes. The associated sfc low should track to Quebec and across the NOrtheast and near the Maritimes Tuesday to Tuesday night with the trailing boundary sagging south across the Great Lakes slowing down and becoming stationary or nearly stationary from VA to the Commonwealth to the Central Plains.

Across eastern KY, temperatures should moderate to near normal with lows Monday night above normal due to increased cloud cover as low and mid level moisture increases. The passing shortwaves followed by the approach of the front from the northwest will result in chances for rain or rain showers at times Monday night to Tuesday night as they interact with moisture that increases from the southwest and west.

Wednesday to Thursday, upper ridging centered in TX and the Gulf north into the Central Conus should build into the MS Valley by Wednesday evening and into the eastern Conus to end the period. The boundary initially over or near the region should shift north in response to the ridging building into the Southeast/OH Valley by later Wednesday to Wednesday night. Sfc low pressure is generally expected to develop over the Northern High Plains by Wednesday and then trek to the western Great Lakes vicinity in advance of the next notable shortwave moving from the Northwest Conus/BC tracks east near the US/Canadian border and nears Ontario the Upper MS Valley/Western Great Lakes having moved around an upper low/trough over the eastern Pacific to west Coast of the Conus vicinity. It is probable that that system and its associated cold front may affect eastern KY about a week from now. Before then, passing shortwaves will result in continued chances for rain showers at times Wednesday and Wednesday night. However, pending timing of the upper ridge axis crossing eastern KY and associated height rises, a min in rain chances may occur on the Christmas Holiday with 00Z operational guidance favoring dry weather on Christmas Day. A trend to temperatures around 10 degrees above normal is the guidance consensus for Wednesday (mid 50s norht to low 60s south) with highs about 15 degrees above normal for the Christmas Holiday. in the warm sector, mainly in the low to mid 60s.

AVIATION

(For the 12Z TAFS through 12Z Saturday morning) ISSUED AT 700 AM EST FRI DEC 19 2025

In the wake of the main cold front exiting the area, MVFR conditions are prevailing for all sites at 12Z TAF issuance due to low clouds. Scattered rain and snow showers will taper off to flurries over the next hour or so. MVFR and IFR CIGs will hang in just past dawn before some clearing and raising of any remaining clouds take place through late morning. Expect VFR conditions by mid afternoon at all sites - holding through the night. Winds will be west at 10 to 15 kts with gusts up to 25 kts initially, settling into the afternoon before going light this evening and continuing that way overnight.

JKL WATCHES/WARNINGS/ADVISORIES

None.