Area Forecast Discussion
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
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954 FXUS63 KOAX 171716 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1216 PM CDT Fri May 17 2024 .KEY MESSAGES... - Hot temperatures today with highs near 90. A bit cooler on Saturday though dry weather continues. - Increased chances for thunderstorms beginning early Sunday and lasting through at least Tuesday. Severe weather will be possible at times, especially Sunday evening and Monday. - The repeated rounds of storms may bring a threat of flash flooding. && .DISCUSSION... Issued at 419 AM CDT Fri May 17 2024 We have mostly clear skies across the area this morning with temperatures in the mid 50s to low 60s. Winds are out of the south but fairly light. We`ll see increasing winds out of the southwest through this afternoon with temperatures jumping up into the upper 80s to around 90 this afternoon as a shortwave passes through ramping up low-level winds. Increased southerly flow and little-to-no cloud cover should allow for excellent mixing which could allow temperatures to even overachieve, so have leaned on the higher side of guidance for temperatures this afternoon. Saturday morning we`ll see a cold front move across the Upper Plains as an upper-level shortwave trough moves across the region. The southwesterly flow regime ahead of this system will keep us too dry for any precipitation with this cold front, but we will see high temperatures drop down into the upper 70s to mid 80s and winds shift to northwesterly. The shortwave trough on Saturday sets us up for a very active pattern going into early next week with a shift to a southwesterly upper-level flow regime. This will bring a strong system through Sunday, with another system on it`s tail moving through on Monday. We see a ramp up of southerly moisture advection out ahead of these systems starting across central Nebraska overnight Saturday night into early Sunday. The low- level jet expands precip chances eastward by Sunday morning, with chances for strong to severe storms Sunday evening as we see a dry line move across the area. Monday we see the surface low move through, likely just to our southeast, which may limit the severe potential to far southeast Nebraska and southwest Iowa. Tuesday temperatures will be a bit cooler as we see a transition from northerly flow behind the Monday front to easterly flow out ahead of the next shortwave. We see the associated surface low track either across eastern Nebraska or northwest Missouri. A more northerly track of the surface low would mean another chance for severe storms Tuesday afternoon and evening. Wednesday, the ensembles start to diverge but we continue to see low chances for showers and storms. We keep these low PoPs and temperatures in the upper 70s to low 80s through Thursday. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1213 PM CDT Fri May 17 2024 Winds will prevail southerly through 12Z tomorrow morning at all TAF sites. Wind gusts up to 35 mph will be possible across northeast Nebraska (KOFK) until 00Z, but more modest estimates have been included in TAFs. Between 21Z and 01Z, there is a low probability of a stray shower or thunderstorms across northeast Nebraska (KOFK). Current probability of rain is 10 to 20 percent. A wind shift is expected sometime at or just beyond the TAF forecast period at all TAF sites from southerly to northwesterly with the passage of a cold front. Will include in TAFs in subsequent issuance. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...McCoy AVIATION...Darrah