Subj : HVYRAIN: Excessive Rainfall Discussion To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Jan 13 2024 08:25:16 FOUS30 KWBC 130825 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 324 AM EST Sat Jan 13 2024 Day 1 Valid 12Z Sat Jan 13 2024 - 12Z Sun Jan 14 2024 ....THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR COASTAL NORTHWEST CALIFORNIA AND A VERY SMALL PORTION OF SOUTHWEST OREGON... ....Northwest Corner of California and Southwest Oregon... On-shore flow of deep moisture will persist today with an additional 2-4" of rainfall...and isolated maximum amounts now closer to 6 inches in the higher terrain... along the coast of coastal northwest California and a portion of adjoining southwest Oregon. Neighborhood probabilities for 5 inch amounts in the 24-hour period ending at 12Z on Sunday was over 60 percent in the within the King Range...with the probability of 2 inch amounts in the same period having a large footprint of at least 50 percent or great encompassing northwest CA and far southwest Oregon. This reflects an expansion compared with the model/deterministic QPF over the 24-hours...and nudges made in the previous outlook still looks good and only a few minor adjustments were needed in this outlook.=20 ....New England... Remnant moisture and some lingering dynamics on the eastern flank of the broad cyclonic circulation over the Great Lakes will continue to support lingering rain across portions of coastal New England today...with rain tapering off later today/tonight as the system finally exits into Canada. Consistent timing in the model mass fields resulted in similar QPF amounts compared with previous forecast cycles...resulting in little need for more than a few cosmetic changes to the outlook. All the rainfall and snowmelt within the past series of events will culminate in some localized flood potential. Bann Day 2 Valid 12Z Sun Jan 14 2024 - 12Z Mon Jan 15 2024 The probability of rainfall exceeding flash flood guidance is less than 5 percent. Bann Day 3 Valid 12Z Mon Jan 15 2024 - 12Z Tue Jan 16 2024 ....THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PARTS OF THE FLORIDA PENINSULA... A cold front will be pushed off the Gulf coast on Monday by an expanding area of high pressure that noses in from the southern Rockies into parts of the adjacent Southern Plains late. This front will be in place as a disturbance embedded within the subtropical jet approaches Monday night or very early Tuesday morning. NCEP guidance is more bullish with QPF over the northeast Gulf and sweeps it across the northern portion of the Florida peninsula...while the ECMWF offered a weaker/faster solution that produced less rainfall. Rainfall has been trending downward over the past couple of model cycles...making this a low-confidence Marginal. Later outlooks may be able to remove this area if the downward trends continue. Bann Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_Bt56mk81EdUeDciOE2qiX-X_sQqKL7650wSbNAxZKo3= YQSEfwElidTKKjo1301Lvsz4si8ndFnQfbZntgPXjto0cqc$=20 Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_Bt56mk81EdUeDciOE2qiX-X_sQqKL7650wSbNAxZKo3= YQSEfwElidTKKjo1301Lvsz4si8ndFnQfbZntgPX0ZoRucM$=20 Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_Bt56mk81EdUeDciOE2qiX-X_sQqKL7650wSbNAxZKo3= YQSEfwElidTKKjo1301Lvsz4si8ndFnQfbZntgPXuWBt8yU$=20 $$ =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .