Area Forecast Discussion
Issued by NWS North Platte, NE
Issued by NWS North Platte, NE
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815 FXUS63 KLBF 300510 AFDLBF Area Forecast Discussion National Weather Service North Platte NE 1210 AM CDT Thu May 30 2024 .KEY MESSAGES... - Severe storms are possible this evening, mainly along and west of highway 61 - Severe storms are possible Thursday afternoon, mainly along and east of highway 83. - Large hail and wind damage are the main concern both days. && .SHORT TERM /THROUGH FRIDAY/... Issued at 333 PM CDT Wed May 29 2024 The CAMs, including the HREF are firing a few areas, or clusters, of storms off the Laramie Range and Pine Ridge around 18z this afternoon. The models generally show modest upscale growth and move the storms in an easterly direction arriving in wrn Nebraska around 23z-00z this evening. A general east southeast motion is expected tonight and weakening is expected by 04z. The storms should continue to drift east through ncntl Nebraska late tonight, carried along by the nocturnal the low level jet. Some of the salient severe weather features are modest winds aloft, 15-30kts at h500-300mb, 20-30kt southerly winds at h850-700mb for effective shear 30-40kts. Strong 850-700mb moisture and theta-e advection is shown by the RAP model this evening. The CAMs wind gust products suggest strong moisture advection and modest shear aloft will cause the storm complexes to form cold pools. Fairly strong WAA will be directed through the WY and Colo ranges and this often produces the severe weather near those ranges. As the storms move away into wrn Nebraska, they weaken. This is the basis for the SPC Day1 outlook of a relatively narrow north-south stripe of severe weather potential along the high Plains. Heating today will cause the warm lapse rates this morning to become steep by late afternoon. The associated MLCAPE, 1000-1500J/KG, supports a large hail threat while damaging winds appear to be the primary severe weather hazard. It is worth noting, the non-CAM RAP model shows just isolated storm coverage; the strength of the CAMs are their ability to predict upscale growth. The models show a weak frontal boundary draped across Nebraska oriented across southwest to northeast Thursday afternoon and this will be the focus for additional storm development mid-afternoon onward, generally along and east of highway 83. For this event, the RAP model suggests scattered storms while the CAMS suggest slightly less storm coverage. The HREF indicates isolated coverage. Winds aloft Thursday are problematic; the westerlies at h500mb back and become south at h300mb. This is not the favored profile for severe storms. Lapse rates, associated MLCAPE and moisture availability are still strong during the daytime. SPC gives just a marginal severe weather risk for this set up. The POP forecast tonight leans on the CAMs and HREF and the RAP model Thursday for likely POPs along and west of highway tonight; mostly east of highway 83 Thursday. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Issued at 333 PM CDT Wed May 29 2024 Sunday and Tuesday are the best chances for thunderstorms in the extended forecast. This storm activity will be guarded by nrn stream disturbances emanating from an upper level low parked across the Gulf of Alaska. Jet winds of 30-40kts at h500-300mb Sunday suggest the potential for severe storms. These winds increase to 40-50kts Tuesday. Isolated storm chances are in place during much of the rest of the extended forecast. The NAM, SREF, GFS and ECM all show isolated storms forming Saturday afternoon, for example. The 850-700mb theta-e advection and moisture transport in both the GFS and ECM support strong storms. The best minds at SPC will make the call on the level of severe weather most likely to develop in later forecasts. For severe weather is possible Saturday through Tuesday. Thereafter, the models are in good agreement amplifying heights across the Rockies. The ongoing heat wave across Mexico will build north into the wrn U.S.. Wrn/ncntl Nebraska will not be in the heart of the heat, but near the ern edge of the ridge. This type of northwest flow appears to be favoring storm development off the Colo Rockies which will dive south through KS and the srn Plains. The forecast is dry next Wednesday. && .AVIATION /06Z TAFS THROUGH 06Z FRIDAY/... Issued at 1201 AM CDT Thu May 30 2024 Scattered -TSRA across southwest and north central Nebraska will continue to move east overnight with no impacts to KLBF and KVTN. Otherwise, VFR conditions are expected at both KLBF and KVTN until at least 12Z. Thereafter, ceilings will lower with MVFR conditions expected at both sites through the early afternoon with a return to low-end VFR conditions for remainder of the period. Southerly winds will veer towards the north/northeast by this afternoon. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...CDC LONG TERM...CDC AVIATION...Viken