Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/15/23


AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
947 PM CDT Sat Oct 14 2023 .UPDATE... Issued at 938 PM CDT Sat Oct 14 2023 Clouds continue to erode nicely from northwest to southeast with much of the west and portions of the north now under a mostly clear sky. For this update, we did decide to go ahead and expand patchy fog mention overnight further north and east to better reflect the latest short term guidance trends. Otherwise, just blended in the latest observations to the forecast and updated the aviation discussion below. UPDATE Issued at 631 PM CDT Sat Oct 14 2023 Most of western and central North Dakota remains under a blanket of clouds. However, clouds will continue to diminish from west to east overnight and into Sunday morning. No major changes were needed for this update. Just blended in the latest observations of the sensible weather fields to the going forecast. && .SHORT TERM...(This Evening through Sunday) Issued at 241 PM CDT Sat Oct 14 2023 The Northern Plains sit under an upper level deformation pattern early this afternoon, with longwave troughing to the east and west and longwave ridging to the north and southwest. At the surface, a meridional ridge axis extends from the Canadian prairie provinces to the Central High Plains. The weak flow regime has allowed cloud cover to remain persistent over much of North Dakota throughout the day. The cloud deck appears to be quite shallow and located between 850 and 800 mb, making its forecast difficult to diagnose using traditional two-dimensional RH fields in deterministic guidance. RAP time cross-sections of RH would suggest a slow erosion of clouds from west to east later this afternoon through tonight, but recent satellite trends show the contrary. Deep layer subsidence will promote dry weather through the short term period. The placement of the cloud cover through the night will likely be the discriminating factor between low temperatures remaining above or falling below freezing. Highs on Sunday will mainly be in the 50s and may approach 60 in the far west. Some guidance is suggesting fog development over far southwest North Dakota early Sunday morning. The kinematic and thermodynamic profiles in model soundings there do not appear to be exceptionally favorable for fog formation, but a mention of patchy fog was added to the forecast in acknowledgement of the consistency of rapid- refresh model trends. .LONG TERM...(Sunday Night through Saturday) Issued at 241 PM CDT Sat Oct 14 2023 The overall theme for the upcoming week is above normal temperatures, with a brief cool down accompanied by chances for rain in the middle of the week. Deep-layer, synoptic scale high pressure and anticyclonic flow are forecast over the central CONUS through Monday, with the upper ridge axis cutting through Montana and surface ridging from western Ontario to Texas. The NBM exhibits high confidence in temperatures rising into the 60s across most of western and central North Dakota on Monday, warmest in the far west where a few 70 degree readings are possible. A potent Pacific Northwest shortwave trough is forecast to quickly eject off the Northern Rockies Tuesday afternoon and dig into the Northern Plains as a closed upper low Tuesday night. The placement of the upstream shortwave Tuesday afternoon will focus the thermal ridge over North Dakota, allowing high temperatures to reach around 65 to 70. Low to medium chances for rain (around 30 to 40 percent in the latest NBM iteration) enter the forecast Tuesday evening and continue through Wednesday until the upper low departs to the southeast. Not every location may see rain with this system, and ensemble 90th percentile QPF only around one tenth to one quarter of an inch point toward a lighter intensity rainfall overall. There is effectively zero probability for thunderstorms or for any precipitation type other than rain. The passage of the trough cools the high temperature forecast back to near normal on Wednesday to the mid and upper 50s. Gusty northwest winds are also possible with the arrival of the cold front attendant to the shortwave Tuesday evening and continuing through Wednesday with the tighter pressure gradient on the backside of the surface low. Guidance favors a longwave upper ridge developing over the western CONUS late next week, though with varying degrees of amplification among ensemble systems and members thereof. Aside from the hint of a late week clipper system in some deterministic models, the resulting anticyclonic flow aloft would favor dry weather and temperatures rising back above normal into the 60s for Thursday into the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 947 PM CDT Sat Oct 14 2023 VFR conditions are expected through the period. 4 kft to 5 kft ceilings will gradually diminish from west to east overnight and into Sunday morning. Some patchy fog is possible across the southwest overnight. The latest short term guidance suggests a bit of a north and east trend for fog development, so it is possible that KDIK could be impacted with lower visibility values overnight and into Sunday morning. Timing and density uncertainty precludes mention in the forecast at this time. Winds will generally be light and variable through the period. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...ZH SHORT TERM...Hollan LONG TERM...Hollan AVIATION...ZH
Area Forecast Discussion
National Weather Service Billings MT
113 PM MDT Sat Oct 14 2023 .DISCUSSION... Tonight through Sunday night... Shortwave energy seen on water vapor imagery and mesoanalysis this afternoon was producing cloud cover as it pushed E into the forecast area. Cooke City and Red Lodge web cams indicated no precipitation, but the NBM had a 15% PoP for high elevations E of Cooke City this evening, so have gone with this forecast. HRRR showed more patchy fog developing tonight, so added that to the grids through early Sunday. Temps tonight will range from the upper 20s in KBHK to the lower 40s in the foothills. Upper ridging builds in for Sunday and Sun. night with dry weather. Highs on Sunday will be mainly in the 60s, with lows Sun. night from the mid 30s to the mid 40s. Arthur Monday through Friday... Monday will be a pre-frontal day, before a ridge breakdown looks to occur on Tuesday as a shortwave and associated cold front move through the region. Highs in the 70s on Monday will give way to 60s on Tuesday. Along with cooler conditions, the shortwave and cold front will bring gusty northwest winds and chances for showers. Wind gusts of 30-45 mph look possible with and behind the front on Tuesday, with breezy conditions continuing over the far east on Wednesday. Precipitation chances Tuesday afternoon and evening are currently 25-50%, with most shower chances shifting east by Wednesday morning. Ridging looks to build back over the region starting Wednesday, and continuing through the remainder of the week bringing drier and warmer conditions. High temperatures will be warming back into the 60s and 70s for most locations, a good 10 to 15 degrees above normal. STP && .AVIATION... VFR will prevail tonight through Sunday. Patchy fog may locally reduce visibilities to MVFR or lower tonight into early Sunday. Arthur && .PRELIMINARY POINT TEMP/POPS... Sun Mon Tue Wed Thu Fri Sat ----------------------------------------------------------- BIL 040/068 046/074 052/069 043/068 047/076 050/076 048/073 00/U 00/B 03/W 10/U 00/U 00/U 00/U LVM 037/068 041/075 046/064 038/066 044/073 044/076 044/074 00/U 00/B 13/W 10/U 00/U 00/U 01/B HDN 035/069 039/076 045/070 040/067 043/076 043/076 042/074 00/U 00/B 04/W 20/U 00/U 00/U 00/U MLS 033/064 039/073 046/067 044/060 041/071 046/072 042/070 00/U 00/B 02/W 31/B 00/U 00/U 00/U 4BQ 033/065 040/073 045/069 044/062 042/071 046/073 044/073 00/U 00/B 02/W 31/N 00/U 00/U 00/U BHK 029/059 036/070 044/067 041/057 037/066 042/068 040/066 00/B 00/B 01/B 21/N 00/U 00/U 00/U SHR 033/066 038/074 044/069 038/063 041/072 044/074 042/073 00/U 00/U 03/W 30/U 00/U 00/U 00/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
629 PM CDT Sat Oct 14 2023 .Discussion... Issued at 356 PM CDT SAT OCT 14 2023 Key Messages: - Cooler, Cloudy, Drizzle/Rain Tonight - Gradual Warm Up Through The Week Discussion: Deep H5 trough has moved over the Great Lakes Region as well as the attendant surface cyclone. The cold front is well into the southeast CONUS. The lower Missouri River Valley is still on the backside of the cyclonic flow. Plenty of moisture has wrapped around the back side this and has kept the stratiform cloud cover across the area. The boundary layer has remained saturated, and kept drizzle in place through much of the morning. There is a secondary short-wave and stronger vort max at 500mb over the Nebraska Sandhills that is moving toward the area. Height falls have already started this afternoon, and the extra lift likely helped to promote more drizzle even with the breezy winds. This will maintain cloud cover for the rest of the evening, and may even keep cloud cover through Sunday as this reinforces the backside of the cyclonic flow. Tonight, the short-wave trough axis moves through and may force a few showers. Overall QPF values are relatively low, less than 0.20 inches. GEFS and other synoptic scale ensembles have covered most of eastern Kansas and western Missouri with some QPF, though members of the HREF have been more conservative with just a few pockets of 0.10 inches. Overall ensemble probabilities for exceeding 0.10 inches this evening is less than 20 percent. Temperatures will drop into the mid 40s. Northwesterly flow will help to bring in more cold air, but the cloud cover should prevent radiational cooling this evening. NBM inner-quartile values for lows tonight are mostly in the 40s. Sunday afternoon, most deterministic solutions amongst NAM/ECMWF/GFS begin to show subtle H5 rises but the short-wave stalls over the western Ohio River Valley, which maintains cyclonic flow across the area. Therefore, will hang onto the cloud cover for much of the day, with HREF holding onto higher probabilities for clouds around 3000- 5000 feet. Drizzle and light showers may be possible while there is enough saturation, but a surface high pressure dropping out of the Plains behind the short-wave trough will bring northwesterly winds and transport drier air toward the area. By tomorrow afternoon, NAM and RAP soundings are relatively dry in the lowest 2500ft which should bring an end to most drizzle if it is ongoing. With the cloud cover, there will not be a considerable diurnal increase in temperatures with highs mostly in the 50s across the area. Monday, H5 ridge just west of the Rockies begins to amplify and will push the deep trough pattern into the Atlantic Coast. This will strengthen northwesterly mid-level flow across the area, and resulting in an AVA regime. The subsidence increase should start to clear out clouds by Monday, as well as strengthen broad surface high pressure across most of the Mississippi River Valley. At 850mb and below, this will turn flow southerly. This does not appear to be overly strong, thus weak WAA will keep the warm up more gradual. This is also reflected amongst NBM and other ensemble clusters, with the mean maximum temperatures only gradually rising through Wednesday with minimal spread with the inner-quartile ranges. The ridge axis quickly moves eastward with another compact short-wave moving from the Northwest CONUS. Heading into late Wednesday and early Thursday, this short-wave will then bring our next forcing and potential for precipitation. Amongst deterministic GFS and ECMWF, there is a timing discrepancy between the two with ECMWF being faster by about 6-8 hours. This is impacting the timing and also amount of QPF for the middle of next week. GEFS members tend to be better agreement with the GFS deterministic solution of a slower solutions which would bring most rain Thursday morning. Overall, QPF looks to remain light with this short-wave, as there is not a long period of return moisture flow on the backside of the exiting surface high pressure. Current ensemble probabilities for exceeding 0.10 inches of QPF for the middle of next week are less than 20 percent at the current moment. Overall, while there will be plenty of forcing around, any areas experiencing drought are not likely to see relief through the middle of the week. && .Aviation...(For the 00Z TAFS through 00Z Sunday Evening) Issued at 620 PM CDT SAT OCT 14 2023 Conditions are currently varying between VFR and MVFR across the region. Ceilings are expected to improve to VFR through tomorrow afternoon. However, confidence is low concerning the timing of cloud decks reaching VFR across the area. Winds will continue from a northerly direction and will gradually weaken through the TAF period. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...NONE. MO...NONE. && $$ Discussion...Krull Aviation...Collier
Area Forecast Discussion
National Weather Service Goodland KS
509 PM MDT Sat Oct 14 2023 .SHORT TERM...(This evening through Monday night) Issued at 250 PM MDT Sat Oct 14 2023 Across the Tri State region this afternoon, skies are mainly sunny for locales along/west of Highway 25, with a persistent low cloud veil still impacting most areas east of Highway 25. Northerly flow remaining over the area with a surface ridge to our north and west, and low pressure east. The latest RAP40 500 mb analysis and water vapor imagery are showing a shortwave digging south over the north central Plains, and another weaker system currently trudging through the central Rockies. For the remainder of the afternoon hours a continued slow erosion of the low cloud deck will continue east, as surface high pressure builds out over the Plains region. The ridge axis will build south over the area tonight allowing for winds to go light/variable for most. The latest HRRR continues to show fog formation potential after 06z Sunday, slowly rolling east into Sunday morning in tandem with the ridge axis. This will continue a previous forecast trend, but have increased the areal coverage of the fog based on newer guidance. The other concern overnight will be how much temps drop compared to last night. Current guidance has areas slightly warmer than last night in spots, but will be highly dependent on cloud cover coming in from the west in association with the Rockies shortwave. Guidance is mixed, but have issued another Freeze Warning for the remaining KS counties from 06z-14z Sunday. Winds should be light enough to support under clear skies, but the aforementioned clouds could dampen the forecasted lows. After getting through the expected cold morning on Sunday, southerly flow will kick in during the day Sunday, persisting into Monday, allowing for a warmup over the 2-day period. For temps, with high pressure pushing south and east over the Plains region in the short term, the area will see highs on Sunday into the lower and mid 60s, giving way to a range on Monday from the upper 60s into the lower 70s. Both days will have the western half of the CWA warmest due to the slow movement of the surface high, putting western zones into the return southerly flow the longest. Overnight lows tonight will range from the upper 20s west into the lower/mid 30s east. Temps west are dependent on cloud cover. Sunday night, lower to mid 30s expected and going into Monday night, a range from the mid 30s to the lower 40s is expected. With the cold overnight lows, wind chill readings in the 20s are forecasted this weekend. .LONG TERM...(Tuesday through Saturday) Issued at 224 PM MDT Sat Oct 14 2023 From the latest runs of the GFS/ECMWF, upper ridge axis does slide across the Plains region on Tuesday/Tuesday night. This will be ahead of a quick moving weak shortwave on Wednesday/Wednesday evening. The passage of this shortwave will bring about a cold frontal passage as well, ushering in a brief cool down midweek. A stronger upper ridge returns for the latter portion of the week, allowing for another warmup to above normal temps by next Friday and Saturday. With the passage of the shortwave/cold front Wednesday, models have been trending lower and lower for any pops in the eastern CWA. The ECMWF is much faster than the GFS, but both are trending to no chance for light showers Wed afternoon/evening. What looks to occur though are increased elevated chances for fire wx concerns Tuesday, Friday and Saturday afternoons. Decent S/SW flow Tuesday afternoon will keep RH values around 20 percent. Upper ridge pushing slowly off the Rockies next Fri/Sat will have NW flow aloft, and zonal/southerly flow. Looking for dry conditions to ensue each day, with the focus along/west of Highway 27. On Tuesday though, decent southwesterly flow at the surface and westerly aloft with upper ridge exiting the area, will afford the CWA another dry day. For temps, highs on Tuesday will range from the upper 70s east of Highway 83, through the lower to mid 80s in areas along and west of Highway 27. The passage of a cold front will drop highs Wednesday into the mid 60s through the lower 70s. For Thursday onward, lower to mid 70s will give way to mainly upper 70s by the first half of the upcoming weekend. For overnight lows, mainly lower to mid 40s are expected, but areas along/west of Highway 27 could see a dip into the upper 30s. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 505 PM MDT Sat Oct 14 2023 GLD: 10-15 knot northerly winds will become light/variable after sunset this evening and remain light/variable through the day on Sunday.. as surface high pressure over the Northern Plains extends southward over the Central Plains. VFR conditions will prevail through the evening, with ceilings confined to cirrus AOA 20,000 ft AGL. With mostly clear skies and light winds, it`s possible that IFR-LIFR fog/stratus may develop early Sunday morning.. depending [perhaps] on the thickness/opacity of orographic cirrus emanating from the Rockies. In other words, less cirrus equals a greater potential for fog/stratus development. The greatest overall potential for IFR-LIFR conditions appears to be in the ~08-14Z time frame. Fog/stratus, if present, will lift and scatter by late morning (15-18Z Sun). Thereafter and otherwise, VFR conditions will prevail. MCK: 10-15 knot northerly winds will become light/variable after sunset this evening and remain light/variable through the day on Sunday.. as surface high pressure over the Northern Plains extends southward over the Central Plains. As of 23Z this afternoon, visible satellite and observational data indicate that low-end VFR ceilings (~3,500 ft AGL) persist.. and that the western periphery of the stratus deck (where cloud cover gives way to clear skies) is situated ~35 nautical miles west of the MCK terminal. With this in mind, stratus may persist well into the evening.. and may (potentially) lower to MVFR. Although the aforementioned stratus deck should gradually erode from west to east this evening into tonight, IFR-LIFR fog/stratus may quickly re-develop early Sunday morning. The greatest overall potential for IFR-LIFR conditions appears to be in the ~08-14Z time frame. Fog/stratus, if present, will lift and scatter by late morning (15-18Z Sun). Thereafter and otherwise, VFR conditions will prevail. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Freeze Warning from midnight MDT /1 AM CDT/ tonight to 8 AM MDT /9 AM CDT/ Sunday for KSZ001-013-027>029-041-042. CO...NONE. NE...NONE. && $$ SHORT TERM...JN LONG TERM...JN AVIATION...Vincent