Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/30/22

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
911 PM CDT Thu Sep 29 2022 .UPDATE... Issued at 906 PM CDT Thu Sep 29 2022 Main issue for the overnight will be watching potential for sprinkles or light showers/thundershowers. Weak lift moves across the region tonight with low-level jet development as well. Latest HRRR runs trying to show isolated sprinkles/showers moving across the CWA overnight. Lower levels of the atmosphere remain rather dry and ceilings would be fairly high. Current radar shows a few blips around KPIR and more "organized" isolated activity across southwest SD that could find its way into the southwest CWA later tonight. May need to add slight chance POPs for the overnight hours and will continue to monitor this potential. Otherwise, the rest of the forecast is on track with little changes needed. UPDATE Issued at 625 PM CDT Thu Sep 29 2022 Aviation discussion updated below for the 00Z TAFs. && .SHORT TERM...(This Evening through Friday Night) Issued at 255 PM CDT Thu Sep 29 2022 The overall 500mb pattern through the period will feature a strengthening ridge over the eastern Dakotas as a large low sinks from northern ID to southeastern ID and western WY. Although winds will diminish overnight, they will remain breezy over much of eastern South Dakota. This is in response to our area remaining between large high pressure over the Lower Great Lakes, and an area of low pressure nearing from western South Dakota. The higher elevations of the Sisseton Hills could tap into some of these winds, as a 35 to 45kt low level jet sets up at 900mb out of the south to southwest. Closer to the surface ridge, areas west of the Missouri River will experience lighter winds. We`ll be monitoring the trends over central South Dakota tonight for the potential inclusion of small chance pops. While a couple of CAMs do pick up on the potential for showers over our southwestern counties, the consensus is for dry weather to continue. One of the more robust solutions come from the FV3, which even brings light showers to eastern SD shortly after daybreak Friday as a surge of warm air shifts north across that area. Given the weakening low level jet at that time, and not a lot of other models going in that direction, have opted to keep the forecast dry. Highs Friday will range from the low to mid 70s along and west of the Sisseton Hills, to the upper 70s to mid 80s elsewhere. 850mb temperatures will vary significantly, from around 15C east to closer to 24C over our southwestern counties. At this point, there looks to be a sizable cap set up around 800mb, with mixing to around 850mb at most locations by the end of the day. Showers, and potentially a couple of thunderstorms, could sneak into our central SD counties Friday night. This will be while the surface low stretches from south central SD through western NE/and far eastern CO. .LONG TERM...(Saturday through Thursday) Issued at 255 PM CDT Thu Sep 29 2022 Few chances of precipitation through the long term and continuing warmer than average temperatures through the weekend before cooling down a bit by next week. Clusters are in good agreement and confidence is fairly high with the upper level closed low continuing to stay fairly stationary over the Northern Rockies on Saturday with a shortwave ridge over much of the eastern Northern Plains and Upper Midwest. This is below quite the upper ridge stretched across Canada. Clusters indicate the closed low/trough finally starts to push east over the Northern Plains on Sunday as the shortwave ridge pushes east. (Of note, a few of the ensembles/deterministic models suggest the low opens up within the trough.) By early next week, the troughing pattern pushes east with another ridge building over the western United States bringing us back to northwest flow aloft, ushering in cooler air. The timing of this between the models start to diverge a bit along with a lower amount of confidence. Clusters 8- 10 day outlook continues this overall ridging pattern (difference on the amplitude/position) to our west which will continue to put most of the Northern Plains in a northwest flow aloft. A few shortwaves noted in GFS with this nw flow by the end of next week. With the low/trough and its shortwave energy, NBM indicates (~15- 32%) chance of rain, mainly across our western CWA Saturday. Sunday this rain threat pushes more east and more widespread across the CWA with chances (15-35%). As the trough moves east, continuing widespread chances of precipitation (up to 45% chance) possible Monday-Tuesday before the chances decrease midweek. Temps still above average for the weekend with winds starting out as east/southeast then turning southeast Sunday. We will start to see a more north/northwest flow as the low pushes through and behind it cooling us down to back around average/below average early next week. Again, depending on timing of the exiting trough and building ridge out west. && .AVIATION...(For the 00Z TAFS through 00Z Friday Evening) Issued at 625 PM CDT Thu Sep 29 2022 Terminals KABR,KATY,KPIR,KMBG VFR conditions are forecast through the TAF period. LLWS will be an issue overnight for KABR/KATY and have inserted mention of this into the TAFs. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...TMT SHORT TERM...KF LONG TERM...MMM AVIATION...TMT
Area Forecast Discussion
National Weather Service Amarillo TX
627 PM CDT Thu Sep 29 2022 ...New AVIATION... .SHORT TERM ... (This evening through Friday night) Issued at 228 PM CDT Thu Sep 29 2022 Midlevel satellite water vapor coupled with the 500mb RAP analysis shows the remnants of Ian entering the Atlantic off the eastern Peninsula of Florida today. Meanwhile, the next system is building across the Pacific Northwest. A weak ridge rests between the upper lows including the Panhandles. A surface lee trough has developed today with typical downsloping breezy southwest winds and warm temperatures into the 80s and 90s. Not much will change with the pattern tomorrow other than the weak flow aloft will become more predominantly southwesterly. In addition, the upper low over the Pacific Northwest will have transitioned southeast over Idaho. Similarly, another surface lee low will develop off the Rockies in eastern Colorado with slightly stronger southwest breezes given the potential for tighter pressure gradients. Rutt && .LONG TERM ... (Saturday through next Wednesday) Issued at 228 PM CDT Thu Sep 29 2022 Starting Saturday through early next week, an Omega Block will set up with a ridge over the central and southern Plains. With weak steering flow and with an upper level low over the intermountain west and what could be the remains of T.S. Ian over the Appalachians, this Omega Block pattern will keep the Panhandles dry through early next week. As the upper level low becomes an open wave Tuesday into Wednesday, it will move across the Plains. This will bring us a chance for some rain, around 20-30% at most, favoring the western Panhandles at this time. Temperatures will be near average as we start early October. Meccariello && .AVIATION... (00Z TAFS) Issued at 625 PM CDT Thu Sep 29 2022 All sites are expected to remain VFR through the period. Winds are starting to ease back to under 12kts this evening, but should pick up with winds of 15-20 kts and gusts of 20-30 kts will be possible during the day. Beat && .FIRE WEATHER... Elevated fire weather conditions return to a portion of the Panhandles today and tomorrow. ERCs are quickly approaching the 80th to 90th percentile across the Oklahoma Panhandle and the 70th and 80th percentile across the Texas Panhandle. Despite the green grasses, recent lack of rainfall and continued hot temperatures are leading to fuels becoming more susceptible for fires. Winds are expected to become breezy around 15 to 25 mph both today and tomorrow across the western Oklahoma Panhandle and northwest and north central Texas Panhandle. In addition, relative humidity values are dipping into the mid to upper teens across a similar portion of the area. Red Flag Warning conditions are not quite there with fuels still transitioning in some places and the weather pattern not having a strong signal for wildfire outbreaks. Rutt && .PRELIMINARY POINT TEMPS/POPS... Amarillo TX 56 86 55 86 / 0 0 0 0 Beaver OK 58 90 57 89 / 0 0 0 0 Boise City OK 57 85 52 84 / 0 0 0 0 Borger TX 59 91 59 90 / 0 0 0 0 Boys Ranch TX 57 87 55 87 / 0 0 0 0 Canyon TX 55 86 55 86 / 0 0 0 0 Clarendon TX 56 86 55 85 / 0 0 0 0 Dalhart TX 54 85 50 85 / 0 0 0 0 Guymon OK 57 89 55 88 / 0 0 0 0 Hereford TX 53 87 55 87 / 0 0 0 0 Lipscomb TX 58 88 55 88 / 0 0 0 0 Pampa TX 57 87 57 87 / 0 0 0 0 Shamrock TX 56 86 55 87 / 0 0 0 0 Wellington TX 56 86 55 87 / 0 0 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...None. OK...None. && $$ SHORT TERM...23 LONG TERM....29 AVIATION...16
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
804 PM EDT Thu Sep 29 2022 .AVIATION... Sprawling surface high pressure is in place throughout much of eastern North America with a local maximum invof of southwestern Ontario and Southeast Michigan. Winds have already become variable to calm which signals textbook conditions for radiative cooling overnight. The question comes down to whether or not there will be fog as there is some potential to favor a heavy dew formation. Surface dewpoints remain elevated in the lower 40s so not overly concerned about frost. Given the long night, do think there will be shot for some shallow ground fog right at daybreak/after 10Z. The MOS signal is bearish at Metro and the HRRR surface pressure deficit progs suggests immediately adjacent/shoreline to Lake Erie and Lake St Clair. DTW THRESHOLD PROBABILITIES... * Low for ceilings aob 5kft tonight. * Low for ceiling 200 ft and/or visibility 1/2 SM towards sunrise Friday morning. && .PREV DISCUSSION... Issued at 255 PM EDT Thu Sep 29 2022 DISCUSSION... Sprawling high pressure centered over Lower Michigan with the center checking in at 1036 MB this morning (still holding around 1034 MB this afternoon). 12z DTX showed a good subsidence inversion, with very dry mid level air as 700 MB dew pt depression came in at 45 C. Some low level moisture, enhanced by the Great Lakes, remains trapped underneath the inversion. In fact, low clouds are still hanging around at press time over Central/Southern sections of the CWA, holding high temperatures near 60 degrees. Further lowering of inversion heights should dissipate these clouds, but the 12z NAM is still indicating high RH (~85 percent) values at the 925 MB level. With the near surface flow becoming easterly overnight, Lake Erie will become a player for areas toward the Ohio border, in addition to Lake Huron for northern areas. Otherwise, favorable radiating night and still some modest surface moisture (indicated by current dew pts in the upper 30s to lower 40s) which will likely be conducive for areas of fog (locally dense) as temperatures reach those values. There is a weak upper level wave coming out of the Midwest which could lead to some high clouds, but probably limited on the extent and not much of a factor. A stronger upper level wave looks to be slowly tracking through Western Great Lakes tomorrow and into Lower Michigan Friday night. Not expecting an impact to sensible weather however, as high degree of low level static stability will be in place with 850 MB moisture confined to Mid Atlantic States/southern Ohio. Remnants of Ian/500 MB low progged to reach the Central Appalachians by Saturday, and it appears the return of a massive/strong high pressure building along the southern Ontario/Quebec border will be sufficient to keep us dry through the Weekend into early next week. Fairly tight pressure gradient will allow for northeast winds over the weekend, peaking in 20-30 mph range, with the afternoon hours being the favored time frame with the deepest boundary layer mixing. Medium range models then suggest an amplified trough/strong 500 MB low sweeping into Eastern Canada for the end of the work week, delivering a very healthy cold shot, as 850 MB temps progged to lower to -4 C in the Thursday/Friday time-frame per Euro. MARINE... Quiet marine conditions continue through remainder of the work week as high pressure drifts directly over the central Great Lakes. Light, largely variable winds shift to the northeast and increase in strength over the course of Saturday in response to the remnants of Ian advancing into the Mid-Atlantic states. Tightened local pressure gradient will support peak gusts up in the 25-30kt range, particularly over central Lake Huron, late Saturday. Winds gradually weaken to finish the weekend/start the next week as Ian`s remnants move back east out over the Atlantic. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....CB DISCUSSION...SF MARINE.......KDK You can obtain your latest National Weather Service forecasts online at
Area Forecast Discussion
National Weather Service Green Bay WI
1007 PM CDT Thu Sep 29 2022 Updated aviation portion for 06Z TAF issuance .SHORT TERM...Tonight and Friday Issued at 223 PM CDT Thu Sep 29 2022 The latest RAP analysis and satellite/radar imagery show high pressure stretching from Wisconsin to the eastern Great Lakes early this afternoon. 12Z regional raobs show ample dry air exists below about 15 kft while satellite-derived total precipitable water values are running between 50-75% of normal from eastern Minnesota into Wisconsin. Weak shortwave impulses are pushing areas of mid and high clouds across the northern Mississippi Valley with a few radar returns showing up across northern Minnesota and eastern North Dakota. Many of these returns are likely reaching the ground northwest of Duluth. Forecast concerns mainly revolve around the chance of light rain over far northern WI tonight, followed by temps. Tonight and Friday...The shortwave impulse over northern Minnesota will track east and send a few showers towards north-central WI by this evening. Mid-level lapse rates won`t be quite as robust further east, so it`s uncertain whether showers will have enough intensity to reach the ground as they fall out of a mid-deck. Will add a sprinkle mention to the forecast north of Rhinelander. There will be more in the way of cloud cover tonight, so min temps should be warm enough to prevent another round of frost. Still though, patchy frost appears possible north of the Fox Valley where lows in the mid 30s are expected. High pressure will have drifted just enough east for light southerly return flow to take place on Friday. Some of the warming from this return flow will be offset by cloud cover associated with the lingering weak shortwave energy aloft. Similar to tonight, any showers will be falling out of a 10 kft deck and have a difficult time reaching the ground. Will see how the showers evolve tonight before adding small precip chances across the north for Friday. Under partly cloudy skies, temps should warm into the middle 60s at most locations. .LONG TERM...Friday Night Through Thursday Issued at 223 PM CDT Thu Sep 29 2022 Forecast concerns: Timing of the next rain chances next week. Otherwise, focus mainly revolves around temperatures. Friday night through Saturday night...Weak shortwave impulses will be traversing the region on Friday night and Saturday. But a surface ridge axis will be extending south across northeast Wisconsin during this time frame. Forecast soundings show ample dry air associated with the surface ridge, particularly below 10 kft. While there will likely be mid and high clouds overhead at times, saturation is not low or deep enough for a chance of precip. Very little change to forecast temperatures, which should be near to slightly above normal. Rest of the forecast...High pressure over Canada will build into the region on Sunday and Monday. 850mb temperatures cool a few degrees on Sunday behind a dry cold front, so should see highs fall back into the lower to middle 60s. The next cold front is forecast to arrive in the Tuesday to Wednesday time period. Temperatures should rebound ahead of the front somewhat on Tuesday before clouds and a chance of light rain arrives with the front. && .AVIATION...for 06Z TAF Issuance Issued at 1004 PM CDT Thu Sep 29 2022 Favorable aviation weather conditions will continue through Friday evening as ridging remains centered just southeast of the area. Middle clouds will stream across the area from time to time and could produce a few sprinkles in the north, but VFR conditions are anticipated. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM.....MPC LONG TERM......MPC AVIATION.......Skowronski
Area Forecast Discussion
National Weather Service Tucson AZ
206 PM MST Thu Sep 29 2022 .SYNOPSIS... Scattered afternoon and evening showers and thunderstorms are expected across parts of southern Arizona through Saturday with highest chances south and west of Tucson. Chances decrease Sunday into next week but isolated storms will still be present each afternoon, especially over the higher elevations. Temperatures remain near normal for the next several days. && .DISCUSSION...Today through Wednesday. Light shower activity continues to develop early this afternoon along with a couple of storms on the northern edge of a mid-level low centered just south of the international border. The cloud cover from earlier today has inhibited destabilization and latest RAP mesoanalysis focuses any SBCAPE south of Tucson over Santa Cruz County. CAMs have picked up on this trend and backed off quite a bit since this morning regarding convective development this afternoon. By tomorrow, clearing in the cloud cover should allow for improved diurnal heating. The mid-level trough will still be situated to our south which will provide some additional upper level support. This support combined with instability and sufficient moisture still in place should lead to more scattered storm activity on Friday afternoon and evening. Storm chances remain highest along the border at roughly 50%-60% in closest proximity to the low then chances decrease as you head northward. Tucson is currently running a 40%-50% chance for rain so we could add some additional rainfall onto the monsoon total on the last official day of the monsoon. Heading into the weekend, the low continues to meander to our south as a more pronounced trough settles over the Great Basin to the north. Scattered showers and storms will continue into Saturday as a result before the trough to the south weakens and opens up going into Sunday. The Great Basin trough will also shift eastward with a ridge building over much of the western U.S. early next week. Moisture will decrease slightly late in the weekend through early next week but there will still be enough to support isolated to scattered storms pretty much each day through Wednesday. The higher elevations will see the best chances each day with more isolated activity across the lower elevations. Temperatures will remain consistently near normal for this time of year with lows dropping a couple of degrees this weekend into early next week as moisture decreases slightly. && .AVIATION...Valid through 30/12z. SCT/BKN at KTUS and BKN/OVC at KOLS between 6-11k ft agl this afternoon. Expect this to continue through this evening with SCT TSRA/SHRA at KOLS and ISO SHRA around KTUS through 30/02z. SFC winds remain E/SE around 6-11 kts with the occasional gusts around 20 kts also through 20/02z when gusts will subside as speeds drop to around 8 kts or less overnight. Gusty outflow winds and brief visibility reductions in heavy rain possible with TS. Another day of SCT SHRA/TSRA is expected for Thursday after 20z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER... Scattered afternoon and evening showers and thunderstorms are expected through Saturday, generally from Tucson south and west. The main threat from the storms besides lightning will be strong and gusty outflow winds. Storm chances will decrease Sunday into early next week but isolated activity is still expected each afternoon. 20-foot winds will remain less than 15 kts each afternoon. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Guillet Visit us on Facebook...Twitter...YouTube...and at