Area Forecast Discussion
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
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
893 FXUS63 KOAX 220546 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1246 AM CDT Sat Jun 22 2024 .KEY MESSAGES... - Main focus will be centered around severe thunderstorms tonight and the potential for continued heavy rain across our north. - Flood Watch for northeast Nebraska and along the entire Missouri River. - At least small storm chances nearly every day through the middle of next week. Severe weather will be possible at times. - Gradually warming temperatures through the weekend into early next week. Heat indices approaching 100 to 110 on Monday and possibly Tuesday. && .DISCUSSION... Issued at 346 PM CDT Fri Jun 21 2024 Tonight A nearly stationary surface boundary remains draped just to the north of the Nebraska/South Dakota border and extends into northwest Iowa. This will serve as the primary focus for late afternoon/evening thunderstorm development where instability has increased through the heating of the day. In addition, a remnant MCV from overnight convection remains across southeast SD. The boundary is forecast to slowly sag southward through the evening across northeast Nebraska. Latest CAM output continues to show thunderstorm development near this boundary as large- scale forcing for ascent increases ahead of an approaching weak shortwave. This activity will slowly sag south tonight across northeast Nebraska. There remains a potential for supercells with a few tornadoes along the boundary and a low-end wind/hail threat. These will also be very efficient rain makers. In fact, OAX just had a pop-up brief downpour with a rainfall rate of 1.34"/hr. Heavy rainfall is expected across southeast SD and northeast Neb with some model output on the order of +2.00" as we move into the overnight hours. Storms should sink south and diminish by Saturday morning. As a result of the heavy rainfall upstream last night and the forecast for additional heavy rain, we have hoisted a Flood Watch for a large section of northeast Nebraska and then all areas along the Missouri River. The runoff from recent rain could potentially bring the Missouri River, below Gavins Point Dam, well into flood stage. With more rain expected today and again tonight, the situation looks to worsen. Due to the large amount of water coming down the river, the river will not crest until mid to late next week with some locations reaching moderate flood stage. Saturday into Sunday The above mentioned front will continue to slide south Saturday and is forecast to be south of our entire forecast area by 00z Sunday. The severe weather threat pushes to our east/southeast while surface high pressure builds south into the area Saturday night. By Sunday, strong southerly return flow brings the heat and we will warm up into Monday with upper level ridging overhead. By Monday, temps will peak in the mid to upper 90s with maximum heat indices near 105. HeatRisk will move into the Red/Major category on both days suggesting a need for effective cooling and hydration for anyone spending time in the afternoon sun. Heat headlines will likely need to be explored. Next week A continued active pattern will carry us to the end of June. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 631 PM CDT Fri Jun 21 2024 Rain and embedded TS continue to move across the region, likely to continue for a few hours at OFK, and will come very close to impacting LNK and OMA. At this time, believe OMA will have a couple hours of TS likelihood, while LNK may just have it in the vicinity. Both LNK/OMA will also have an outflow boundary move through with a wind shift out of the northwest, which will last for a couple hours before turning back out of the south. LLWS will continue at all sites tonight. A cold front will move through all site during the day on Saturday, with lower MVFR cigs at OFK after the front passes, but probably in the VFR category at OMA/LNK as it passes a bit later in the day. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Flood Watch until 7 AM CDT this morning for NEZ011-012-016>018- 030>033-042-043. IA...None. && $$ DISCUSSION...Kern AVIATION...Barjenbruch