Area Forecast Discussion
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
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709 FXUS63 KOAX 030436 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1136 PM CDT Tue Jul 2 2024 .KEY MESSAGES... - Scattered strong to severe thunderstorms are possible this afternoon and evening across portions of southeast Nebraska and southwest Iowa. The primary hazard will be damaging winds, though a tornado or two cannot be ruled out. - Additional rounds of thunderstorms will be possible Wednesday night through Thursday evening. - A third system will bring another potential round of rain and thunderstorms to the region this weekend. && .DISCUSSION... Issued at 324 PM CDT Tue Jul 2 2024 The cold front is currently draped across the southeastern portions of our forecast area, with far southeast Iowa the only area left in the warm sector ahead of the front. This is the best area to see some severe weather this afternoon. Shear and instability behind the front could support a stronger updraft or two behind the front as well, but it will be much harder. Skies will be clearing as showers move out of the area this evening with high pressure sliding across the area overnight. This will lead to winds becoming nearly calm leading to nearly ideal conditions for fog development overnight. Best area for fog development will likely be along and east of the Missouri River. Fog should clear by mid-morning on Wednesday leading to a fairly nice summer day with partly cloudy skies and highs in the mid-80s. We`re watching Wednesday night into Thursday morning as an upper-level trough swings through bringing another MCS across our area with potential for additional severe weather. Storms will develop again out over the Nebraska Panhandle and morph into a line of storms by the time they reach central Nebraska. This line of storms will continue east, with some question how long it will hold together before it weakens as it moves into a more stable environment across eastern Nebraska into western Iowa. We could still see some potential for damaging winds and large hail, though, with the highest risk for our western counties. During the day on Thursday, for the Fourth of July holiday, the base of the upper-level trough swings through transitioning our upper-level flow pattern from southwesterly to a slightly tamer northwesterly flow regime. This will continue shower and storm potential through the day, though heavier rain will fall to our north across eastern South Dakota into northwest Iowa and southwest Minnesota. We could potentially see significant rainfall in this area to the north which may reinvigorate the flooding along the Missouri River going into next weekend and beyond so we will want to watch this closely. Though rain may dampen spirits on the holiday, I don`t think it will be a complete washout. Precip chances will be decreasing through the afternoon into the evening, and many areas may clear out just in time for evening fireworks displays. Friday and Saturday are looking dry after the pattern shift. Friday will be very mild with high temperatures only in the upper 70s, and a bit warmer on Saturday with highs in the low- to-mid 80s. Our next chance of rain looks to be with our first MCS of the northwesterly flow regime Saturday night into early Sunday, so we`ll want to monitor this period for potential severe weather and heavy rainfall. Low shower chances continue through the day on Sunday. This type of pattern lends to uncertainty farther out in the forecast and generally doesn`t pick up on subtler shortwaves, so we could potentially see another MCS early next week, but right now models keep the forecast dry on Monday. Trends show a warmer pattern for next week with potential for overnight MCS`s as the stationary ridge to our west remains in place. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1136 PM CDT Tue Jul 2 2024 Light winds, mostly clear skies, and residual moisture will favor fog development tonight, especially at LNK and OMA. However, confidence in density and how widespread it becomes is on the lower side as guidance has trended toward less coverage and continues to bring in some mid to high level clouds. At OFK, thinking winds aloft will stay too strong for widespread development, though can`t completely rule out reductions there. Otherwise, VFR conditions are expected with light westerly/southwesterly winds overnight becoming southeasterly Wednesday afternoon. A few hints at some light showers in southeast Nebraska around 17Z to 21Z, but not much should hit the ground and consensus keeps them south of the TAF sites. Additional storms may move in toward the very end of the period, but exact timing and coverage remain in question. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...McCoy AVIATION...CA