Area Forecast Discussion
Issued by NWS Louisville, KY
Issued by NWS Louisville, KY
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
337 FXUS63 KLMK 230721 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 321 AM EDT Thu May 23 2024 .KEY MESSAGES... * Strong/severe storms possible region wide this afternoon with damaging winds, hail, and very heavy rainfall being the main threats. * Stormy pattern with a risk for localized flooding Thursday through Tuesday with strong/severe storms possible Sunday. && .SHORT TERM /THROUGH TONIGHT/... Issued at 320 AM EDT Thu May 23 2024 Remainder of the Overnight and into the Morning... A 35-40kt LLJ located over the KY/TN border and a stalled surface front over the Ohio River has allowed for convective initiation within the last hour. As these showers and storms move NE, they will be separated from the best (although weak) forcing and have very limited instability to work with. Low stratus over the I-64 corridor and north will remain until sunrise. Patchy fog is possible in low lying areas. Mid-morning through Early Afternoon... Model guidance is not initiating well with current early morning convection. However, given radar trends, much of the morning and into the afternoon will likely remain dry. Drier conditions will allow for increased heating and increased instability potential. Mid 60s dew points and high temperatures in the upper 70s and low 80s will lead to muggy conditions. Late Afternoon - Evening... Weak shortwave troughing and CVA will move over the region in the afternoon. This feature, coupled with the stalled surface front and ample moisture will allow for scattered convective initiation over the region. Weak, but sufficient shear will keep convection disorganized and pulse-like. Main threats will be gusty to damaging winds, heavy rain with downbursts, and marginal hail. Very limited tornado threat due to weak low-level shear. Thursday Night into Friday Morning... With sunset, the nocturnal inversion will settle into the region and convection will dissipate. The remainder of the night will feature weak ridging, thinning skies, and calm to light winds. These conditions coupled with recent precip will likely bring some patchy fog to the region in the early morning hours. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Issued at 320 AM EDT Thu May 23 2024 Overall unsettled pattern through the holiday weekend, with multiple waves of showers and storms, but also dry periods in between. Best chances for dry weather will be Saturday and Saturday night, with fairly widespread showers and storms for portions of Friday and especially Sunday. Organized severe weather is also in play on Sunday. The upper pattern Friday is quasi-zonal without much phasing between the northern and southern streams. Sfc warm sector will push PWATs up to 1.5 inches or more, with decent instability but not much shear. Could see gusty winds, perhaps near-severe, with the steep low-level lapse rates, as well as brief heavy rainfall resulting in localized flooding. Can`t rule out isolated/scattered convection on Saturday but that should be a mostly dry day. Sunday is the most interesting day with a sub-1000mb sfc low tracking to our north, moderate instability and strong speed and directional shear. Organized severe weather is possible with all modes on the table including tornadoes. SPC extended outlook highlights central and western Kentucky, so all interests in the lower Ohio Valley should remain weather aware through the holiday weekend. Cold front pushes through early Monday, but cyclonic flow will mean a slow exit for precipitation. Better chances for dry weather Tue- Wed under a more NW flow regime, with temps on the lower side of climo. && .AVIATION /06Z TAFS THROUGH 12Z FRIDAY/... Issued at 320 AM EDT Thu May 23 2024 Low stratus is building over I-64 terminals and will continue through the remainder of the early morning. Radar shows some convection beginning to develop over north-central TN and southern IL along a cold front and weak LLJ, respectively. As these showers and storms move NE through the Ohio Valley, they will incur very limited instability and little forcing for sustainability. Showers and storms are most likely to impact BWG and HNB, while keeping other terminals precip free until the afternoon. In the afternoon, instability will increase over the region and coupled with a frontal boundary and mid-level shortwave will allow for convective initiation. VCTS is expected at all terminals with some TSRA possible. Further TAF issuances will be able to narrow a timeframe for convective impacts. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ SHORT TERM...SRM LONG TERM...RAS AVIATION...SRM