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
838 FXUS64 KMRX 021728 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 128 PM EDT Sun Jun 2 2024 ...New AVIATION... .UPDATE... Issued at 1148 AM EDT Sun Jun 2 2024 Forecast is on track this morning with rain showers moving across the region through the early afternoon. Convection should be primarily across the eastern portions of the forecast area later this afternoon, generally east of I-75, with rain showers and embedded thunderstorms. With limited instability, severe thunderstorms are not expected. && .SHORT TERM... (Today and tonight) Issued at 309 AM EDT Sun Jun 2 2024 Key Messages: 1. Breezy winds continue across the east TN mountains and foothills through late morning, with gusts up to 35 mph. 2. Scattered to widespread showers, and scattered storms, are expected today. Skies begin to clear west of I-75 by late afternoon. Discussion: 30 to 35 kt winds at 850 mb will continue to produce breezy winds across the east TN mountains and foothills through at least mid morning. Wind gusts up to 35 mph are expected. A shortwave is currently moving into the area this morning and producing light and scattered showers. Coverage of showers and storms should increase to our west by mid morning. Then, scattered to widespread showers and storms will move across the area through the day as the shortwave moves marches through. Soundings continue to show 1000 to 1500 J/Kg MLCAPE. Effective shear still ranges from 15 to 20 kts so perhaps enough to keep convection loosely organized but non severe, just general thunder. Areas west of I-75 should begin to see clearing by late afternoon as precip moves east. Most areas will see less than 0.25 inches. However, any location that receives a thunderstorm could pick up a quick 0.5 to 0.75 inches of rain. The bulk of the precip should be finished by early evening for the majority of the area. This is due to the shortwave exiting east and drier air beginning to build in from the west. However, lingering moisture will likely keep at least iso/sct showers in through midnight east of I-75, especially across northeast TN, southwest VA, southwest NC, and the east TN mountains. && .LONG TERM... (Monday through Saturday) Issued at 309 AM EDT Sun Jun 2 2024 Key Messages: 1. Daily chances of showers and thunderstorms exist throughout the extended. Best chance/highest coverage is expected Wednesday and Thursday. 2. Above normal temperatures will trend slightly cooler late week and into the weekend. Discussion: Shortwave ridging will limit coverage of a more diurnal trend in showers & storms for Monday, The best chances(30-40%) will generally be focused across higher terrain of the East Tennessee mountains. Model derived soundings from convective allowing models suggest MLCAPE will be limited to near 500J/kg or less. No concerns for any severe weather as a result. Vort lobes will swing across the area associated with additional disturbances Tuesday into the late week, allowing for daily chances of showers and storms to persist. Will note that model guidance has generally trended downward, with Tuesday looking more like typical summertime diurnally driven activity. An additional frontal boundary will approach the region Wednesday into Thursday and result in heightened coverage of showers and storms. Ensemble guidance trends towards increasing instability with this activity so perhaps stronger storms with gusty winds and small hail cannot be ruled out. Based off recent soundings, Wednesday seems to be the most likely day to keep an eye on for potential severe threat. Additionally, PWAT hovering around 1.7" may pose a threat for locally heavy rainfall and possible flash flooding concerns. Still some timing discrepancies among models however, and timing will play an important role in the aforementioned potential hazards. Given there are no significant jet influences across our area(they remain to our north-northwest), overnight arrival of the main frontal forcing would lead to less available energy for storms to work with. Will continue with low probability wording for the time being. Continued uncertainty remains into the weekend as some models depict lingering rain chances and others mostly dry. Slightly cooler conditions are expected in a post-frontal air mass for the weekend as well, though weak frontal characteristics suggest only a few degrees difference from mid-late week temperatures. && .AVIATION... (18Z TAFS) Issued at 125 PM EDT Sun Jun 2 2024 Rain showers will continue to move east this afternoon with generally clearing conditions from west to east. There is a low chance of a thunderstorm in the vicinity of terminals this afternoon, but with the probability only around 10 percent, have left this out of the TAF at this time. The highest risk of a thunderstorm this afternoon, around 20 percent, will be at CHA. With clearing sky conditions tonight, especially near CHA and TYS, widespread fog and low cloud development is expected across the valley with MVFR and IFR impacts by Monday morning. Conditions will improve to VFR by 14 to 15z Monday morning. Winds remain light. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 82 66 87 67 / 70 10 10 0 Knoxville McGhee Tyson Airport, TN 78 63 85 64 / 80 20 10 0 Oak Ridge, TN 77 63 85 64 / 80 20 10 0 Tri Cities Airport, TN 76 61 81 61 / 80 30 30 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM... LONG TERM....KRS AVIATION...JB