Flash Flood Guidance
Issued by NWS
Issued by NWS
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017 AWUS01 KWNH 280701 FFGMPD MOZ000-ARZ000-TXZ000-OKZ000-281300- Mesoscale Precipitation Discussion 0192 NWS Weather Prediction Center College Park MD 301 AM EDT Sun Apr 28 2024 Areas affected...Northern TX...Eastern OK...Western AR Concerning...Heavy rainfall...Flash flooding likely Valid 280700Z - 281300Z SUMMARY...Numerous to widespread areas of flash flooding are likely over the next several hours for areas of northern TX through eastern OK. Locally significant and life-threatening impacts are expected. DISCUSSION...The latest GOES-E IR satellite imagery in conjunction with regional dual-pol radars show an elongated and strong QLCS advancing gradually off to the east-northeast across northern TX and eastern OK. The portion of the line that is generally southwest of the Dallas-Fort Worth metroplex is advancing a bit more progressively off to the east, but there is evidence in surface observations of an area of low pressure riding up along the convective line which is resulting in a wavy structure that includes very strong convection over southern and eastern OK that is tending to slow its forward propagation. A nose of MLCAPE values on the order of 1500 to 2500 J/Kg remain in place across the broader Red River Valley with the greatest instability nosing up through northern TX and into southern OK. There is a corridor of very strong and deep moisture convergence across the region, with the latest CIRA-ALPW data reflecting strengthening layered vapor transport (LVT) magnitudes all the way up through 700mb. VWP data does indicate a 50 to 60+ kt low-level jet in place and this coupled with the stronger forcing in vicinity of the QLCS is resulting extremely heavy rainfall rates that are in the 2 to 3+ inch/hour range. The level of instability should tend to wane ever so gradually across the Red River Valley over the next few hours heading through sunrise, but the rainfall rates are expected to remain quite high as the QLCS continues to gradually advance off to the east-northeast early this morning. The biggest concern with the early morning setup will be the localized persistence of these extreme rainfall rates, as areas very slow cell-motions and cell-training occur. Expect areas locally in far northern TX, and south-central to eastern OK, to see in excess of 5 inches of rain in as little as 2 to 3 hours. This will include areas along a line from near Gainesville, TX northeastward up through McAlester and Stigler in eastern OK. Areas farther south across northern TX, generally south of the Dallas-Fort Worth metroplex will see lesser amounts, but even here there may be locally as much as 2 to 4 inches of rain through early this morning. Numerous to widespread flash flooding is likely and some areas are expected to see significant and life-threatening impacts. Orrison ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...FWD...LZK...OUN...SGF...SHV...SJT...TSA... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 36639399 36039354 34889387 33369498 32029655 31559784 31699875 32229891 33139841 34179745 35289630 36479504