Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
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
727 FXUS64 KMRX 110613 AAC AFDMRX Area Forecast Discussion...UPDATED National Weather Service Morristown TN 213 AM EDT Sat May 11 2024 ...New AVIATION... .UPDATE... Issued at 935 PM EDT Fri May 10 2024 A quiet Friday evening with no big forecast updates. Made slight adjustments to hourly temps and dewpoints to match up with latest obs but otherwise no changes. && .SHORT TERM... (This evening through Saturday) Issued at 303 PM EDT Fri May 10 2024 Key Message: Scattered showers and some thunderstorms expected this afternoon should dissipate after sunset. Discussion: Currently there are showers and a few thunderstorms present across northeast Tennessee and southwest Virginia as a shortwave is likely directly above us moving east/southeast. This also in conjunction with an upper level jet moving through the Tennessee Valley that is providing additional divergence aloft. Based on this synoptic set up and additional CAM guidance it still looks like the greatest coverage of storms and best chances to see lightning will be along and north of Interstate 40 this afternoon/evening. Storms that have already developed are moving southeast at around 20 mph, which will hopefully limit the flooding potential of them... But they could produce enough rainfall in to slightly re-aggravate flood prone areas this afternoon. But more widespread flooding is not anticipated at this time. As we move into the evening and overnight hours the shortwave and diurnal heating will both be over with and we`ll return to quiet weather. In addition the winds should slack off and we`ll likely see some patchy fog develop, especially in the river valleys and areas that still have some standing water from the recent rainfall. With the clearer skies and light northwest winds we`ll see temperatures drop to near 50 south of I-40 and into the 40`s for many places north of the Interstate. Tomorrow should be a similar story as today with afternoon showers and some thunderstorms expected to develop again. However, coverage should be less tomorrow with worse synoptic forcing in the region. && .LONG TERM... (Saturday night through next Friday) Issued at 303 PM EDT Fri May 10 2024 Key Messages: 1. Dry weather and near normal or slightly below normal temps to finish out the weekend on Sunday. 2. An active pattern sets up starting Monday afternoon, with rain and thunderstorm chances through at least Wednesday. Discussion: On Sunday, a ridge is moving into the region from the west. Sunday will be dry and sunny with highs around or slightly below normal as northerly flow continues in the lower levels. By Monday afternoon, high pressure is still over the Southeast but the ridge is drifting eastward as a trough is moving into the Mississippi Valley. POPs start to increase Monday afternoon but Tuesday has higher chances for showers and storms as that trough and a vertically stacked surface low move into the Ohio and Tennessee Valleys. By Wednesday afternoon or night a ridge starts to build into the region but another system may move in by Friday. Overall, a wet pattern will be in place next week with forecast rain totals of 1 to 2 inches. Instability does not look too impressive with dew points mainly in the lower 60s. A few strong to severe storms cannot be ruled out particularly Tuesday when shear looks most favorable but confidence is low this far out. With a wet pattern in place next week, highs will be near or below normal with increased cloud cover. && .AVIATION... (06Z TAFS) Issued at 208 AM EDT Sat May 11 2024 VFR conditions expected for much of the 06z TAF period. The exception may be KTRI where some fog is expected to develop over the next few hours. Guidance is mixed on how widespread this becomes, so will leave VSBY restriction capped at 5SM for now. Also have a weak cold front coming in today. Much like yesterday some scattered showers are expected to develop, with coverage being better the further north you go. Think VCSH from 17z - 00z at KTRI will be sufficient, and will leave other terminals dry. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 77 53 80 57 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 72 50 75 52 / 20 10 0 0 Oak Ridge, TN 74 48 77 53 / 20 0 0 0 Tri Cities Airport, TN 67 46 72 47 / 30 10 0 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM... LONG TERM....McD AVIATION...CD