Area Forecast Discussion
Issued by NWS Oklahoma City, OK
Issued by NWS Oklahoma City, OK
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145 FXUS64 KOUN 030508 AFDOUN Area Forecast Discussion National Weather Service Norman OK 1208 AM CDT Fri May 3 2024 ...New AVIATION... .SHORT TERM... (This evening through Friday) Issued at 242 PM CDT Thu May 2 2024 Today`s forecast primarily concerns the potential for severe weather and flooding especially across western north Texas and southern Oklahoma. Regional surface observations and satellite data show a cold front across northern Oklahoma early this afternoon. This front is expected to advance southward toward a position just north of I- 44 by late afternoon. Despite rather persistent cloud cover south of the front, rich boundary-layer moisture will still lead to MLCAPE values around 2,000 across southwest and central Oklahoma, while somewhat greater heating across western north Texas will lead to MLCAPE values around 3,500. CAMs are rather bearish on deep convective development in the face of neutral or slightly rising heights, but storm initiation is likely across two zones. The first zone will be just south of the front, particularly in central Oklahoma. Rather weak deep-layer shear and steering flow primarily moving the storms eastward will encourage the front to undercut this convection fairly rapidly. Prior to that, a low-end risk for damaging winds will occur, as well as the risk for one or two non-supercellular tornadoes very early in the convective cycle as storms have the potential to use moderately strong low-level instability to stretch surface vorticity along the surface front. This convection will tend to propagate southward along the cold front over the evening. The second, and potentially greater severe threat will occur this afternoon and evening across western north Texas along the triple point low. There is some uncertainty primarily related to whether or not the triple point ends up south of our area or not, but one or a few storms will likely develop by late afternoon. Forecast soundings show rather straight hodographs with effective deep-layer shear of about 40-50 knots, sufficient for splitting supercells. Given the strong instability, large to giant hail is probable. Given the strong low-level instability in place and the presence of the surface low, the tornado risk will remain low, but not zero. The threat for storms to persist overnight tonight will be somewhat lower than over the previous several days given the lack of a presence of a low-level jet. However, amalgamation and propagation of cold pools will probably lead to a cluster of storms or an MCS in the Red River Valley as the front continues to push south. A low threat for damaging wind gusts will continue, but the greater concern will be the potential for flooding as storms move over areas that have been deluged over the past week. 1-hour gridded flash flood guidance is below 1 inch across much of the Arbuckles and surrounding terrain features. Thus, while QPFs will likely remain in the 0.25-0.75 inch range across much of the region, there will most likely be a couple of areas that see either training or a stalled storm, and flash flooding could occur rather rapidly in that area. Meister && .LONG TERM... (Friday night through next Wednesday) Issued at 242 PM CDT Thu May 2 2024 The storm risk will reach a relative minimum for the first time in days tomorrow, with storms exiting the southeast portion of the area by early morning and the next round not expected until near of after sunset out west. In the meantime, enjoy the quiet weather, with highs reaching into the upper 70s as the moist airmass sloshes back to the northwest across our area. The next round of storms comes in tomorrow evening and overnight as one or more clusters move eastward off of the Caprock and into our area. A modest low-level jet will be present, so the threat for damaging winds will be rather modest. The likeliest impact will be the potential for another round of heavy rainfall across the Red River region if an MCS is able to sustain itself. The most widespread round of rain over the next several days will be Saturday night, as yet another round of storms moves in from the west. Forecast soundings show deep saturation throughout the troposphere with rather weak steering flow. Right now, our forecast QPFs are in the 2-3 inch range along and south of the Red River, and this will need to be watched very closely in case a serious flash flood concern develops. On Monday, the potential exists for a more widespread severe weather event to occur. Uncertainty is obviously modulated by the multiple rounds of storms that will occur between now and then, and their attendant impacts on the boundary layer, as well as the potential for the primary forcing to remain well to our north across Kansas and Nebraska. With that said, the environment now appears to support supercells with a continued severe/flooding threat. Who knows whether this will last, but there does not appear to be another evident round of storms after Monday/Monday night. Buckle up, folks. The risk for high-impact weather is definitely not over yet. Meister && .AVIATION... (06Z TAFS) Issued at 1203 AM CDT Fri May 3 2024 MVFR and VFR ceilings expected with this TAF period with IFR ceilings possible at a few sites early Friday. Scattered showers/storms will remain possible overnight into early Friday for mainly areas east of the TAF sites except for KDUA. Additional storms will be possible Friday evening but chances too low at some sites for mention. Frontal boundary is expected to slowly move a bit more with NE winds N of the front. Southeasterly winds will return Friday as the front lifts back north as a warm front. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 63 76 61 74 / 40 80 80 80 Hobart OK 60 76 59 76 / 50 80 90 70 Wichita Falls TX 64 79 62 77 / 40 70 80 70 Gage OK 54 71 52 76 / 60 50 70 50 Ponca City OK 60 75 58 73 / 50 80 70 80 Durant OK 66 79 64 77 / 30 60 60 80 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...Flood Watch until 4 AM CDT early this morning for OKZ038-039- 041>048-050>052. TX...Flood Watch until 4 AM CDT early this morning for TXZ090. && $$ SHORT TERM...04 LONG TERM....04 AVIATION...25