Area Forecast Discussion
Issued by NWS Louisville, KY
Issued by NWS Louisville, KY
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068 FXUS63 KLMK 111723 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 123 PM EDT Sat May 11 2024 ...Updated Aviation Discussion... .KEY MESSAGES... * Breezy Saturday with brief light rain possible in southern Indiana and northern portions of central Kentucky. * Lots of sunshine with moderate temperatures and light breezes on Sunday. * Active pattern next week with almost daily chances of showers and storms Monday through Friday. Best chance for a dry day will be Thursday. Severe weather is not expected through at least Thursday. Strong storm chances may increase slightly by Friday. && .UPDATE... Issued at 1032 AM EDT Sat May 11 2024 Low pressure is spinning over the Great Lakes this morning, with a sfc cold front draped southwest along the Ohio River. A band of mid- level clouds just ahead of the boundary extends into central KY. Clear skies are noted in southern IN with winds veering northwesterly. The rest of the day looks mainly dry and breezy with just a few brief showers possible in the eastern CWA. The clouds will continue to quickly clear out from northwest to southeast into early afternoon. Temperatures will warm from the 60s into the low to mid 70s by mid-afternoon with winds gusting to 20-25 mph. Peak wind gusts will approach 30 mph. && .SHORT TERM /THROUGH TONIGHT/... Issued at 326 AM EDT Sat May 11 2024 Currently, satellite imagery shows mostly clear skies over southern Indiana and central Kentucky. A few mid-layer clouds remain, but they are on the move, leaving clear skies behind. Some light fogging can be seen, mostly in the Lake Cumberland area, but for the rest of the night, things should remain quiet as temperatures drop into the mid 40s in the eastern Bluegrass to the low to mid 50s along and west of Interstate 65. To the north, a low pressure system over the Great Lakes has a trailing cold front stretching through the Chicago area. In the coming hours, shortly after sunrise, the front will make it closer to Louisville. This will bring added forcing to a fairly dry atmosphere. Precipitable water values ahead of the front will top out around three quarters of an inch. Model soundings show moisture in the mid-levels, in the 800-700mb level, but below and above that things are dry. Around the 700mb level, an inversion is in place which would further limit convection. With this being said, the front could produce a broken line of showers. The southwest extend is expected to be limited with better chances along and northeast of a line from Louisville to Lexington, but later this afternoon, precipitation chances could extend into the Lake Cumberland region. With the low dry levels, virga will also be possible. The front will provide a better chance for some scattered to broken 5-10,000 foot clouds to pass overhead. Light southwest winds will veer towards the northwest and gust to 20-25 mph as the front passes. This will help hold temperatures to the low to mid 70s for highs. Tonight, surface high pressure to our southwest will move a little father to the east. This will help winds to begin backing as they ease towards the southwest. Model soundings show a near surface inversion and a dry profile, resulting in strong radiative cooling which could result in some patchy fog. Lows are expected to drop into the mid 40s to low 50s. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 326 AM EDT Sat May 11 2024 Sunday - Sunday Night... Dry NW flow aloft and surface high pressure will control our region to end the weekend. This should yield a very nice Sunday with mostly sunny skies and temperatures in the mid to upper 70s. Sunday night also remains dry, although will begin to see some mid and upper sky cover return. Lows will dip into the low and mid 50s. Monday - Wednesday... A closed low over the central Plains will slowly meander toward our region early week, and then over our region and eastward by mid week. This moisture laden system will already have some Pacific moisture, and then will have plenty of time to draw on Gulf of Mexico moisture as it approaches. As a result, expecting PWATs to surge up around 1.5" through the column by Tuesday, lingering around that range through early Wednesday before the center of the system pushes east. Not a whole lot of instability to work with, although there may be a bit more CAPE to work with by Wednesday. Overall, soundings take on a mostly tall/skinny type of profile, and given high PWATs and not a lot of speed shear in the column (slow movement), heavier showers/storms are the biggest concern. Monday starts out dry, however some isolated to scattered showers or possibly a storm could develop by afternoon, mainly west of I-65. From there, Tuesday looks pretty wet with continued categorical pops. Coverage scatters out a bit by Wednesday, but could still have some intense rainfall rates given a bit more instability. Right now, QPF is expected to be mostly in the .75" to 1" through Wednesday. For context, probabilities of greater than 1" through Wednesday are around 40%, but fall to below 20% for greater than 1.25". Temperatures look to be in the 70s each day, with just how warm dependent on breaks in the rain, and perhaps a few peeks at the sun. Wednesday Night - Thursday... Looks like we should get a brief period of dry Wednesday night through Thursday with upper riding and surface high pressure in place. NBM still wants to paint some scattered pops for later Thursday into Thursday night, but I generally like a deterministic consensus over NBM at this range. Looking for highs a degree or two either side of 80. Thursday Night - Friday... Overall consistent signal for another shortwave arriving by late week, although the fine details are still quite erratic amongst the models. In general, it appears that shower and storm chances will increase by Friday ahead of an ejecting system out of the Plains. Looks like there could be more instability to work with, and perhaps more shear too, depending on which model solution ends up verifying. If so, a few stronger storms would be possible. Way to early to speculate more much more than that, but a day to watch. && .AVIATION /18Z TAFS THROUGH 00Z MONDAY/... Issued at 122 PM EDT Sat May 11 2024 VFR conditions are likely through the forecast period. A cold front is dropping southeast through Kentucky this afternoon and could help generate a few showers in the I-75 corridor this afternoon. At this point, RGA would have the best chance (20%) at seeing a brief shower but confidence is low. Coverage will be pretty limited. VFR cumulus continues to clear off to the southeast this afternoon with mainly clear skies overnight. Winds are veering northwesterly in the wake of the cold front, and expect gusts of 20-25 kt through 22-23Z. Winds diminish tonight as the low levels decouple and high pressure slides slowly eastward across TN. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ UPDATE...EBW SHORT TERM...KDW LONG TERM...BJS AVIATION...EBW