Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/13/22

Area Forecast Discussion
National Weather Service Billings MT
818 PM MDT Sun Jun 12 2022 .UPDATE... Another quick update to refresh pops given current conditions. Area of showers w/ embedded thunderstorms exists from near Lodge Grass to Miles City and Baker, and although the risk of severe storms has ended, these elevated storms will produce some heavy rainfall and pockets of small hail. Rainfall is less intense over the west, but stream of Pacific moisture continues to produce healthy rainfall rates over the Beartooth/Absarokas. Satellite imagery shows large area of upper diffluence over southern ID, and the moist southwest flow will continue to produce widespread rain (and high elevation snow) over our southwest mountains thru Monday morning. Focus remains on river levels over the next couple days. JKL && .DISCUSSION... Rest of Today through Monday Night... All eyes are still focused on the flooding concerns over the mountains and foothills, while also still darting over to the far SE and the ever present severe thunderstorm situation that is still expected out there. FLOODING... Latest water vapor imagery shows a large pool of moisture continuously feeding into southern Montana, and prominent upper jet coupling that will continue to provide ample ascent to keep the flow of rain present through Monday. Further supporting the high rain are PWATs 0.8-0.9" in the mountains and foothills. A majority of streams in the Beartooths and Bighorns are already flowing high and fast and reaching minor flood stages, and with rain expected to persist, stream levels will only continue to rise throughout today. Rain won`t begin to lighten and shift east until late Monday morning. For more details, view our Hydrologic Outlook and assortment of Flood Watches and Warnings that are current in place for many areas and streams. THUNDERSTORMS... The ever-present stream of cloud cover and rain has kept much of southern MT on the cool side, and although far SE MT has no cloud cover and is warming up, some north flow is keeping instability lacking out there and waiting south of Montana. As the surface high over far SE MT shifts east, winds should shift to the southeast later this afternoon to introduce instability to the area, which is really the only ingredient lacking in order to get severe thunderstorms to fire up. Otherwise, ample shear is present, with 0.6 km Bulk Shear values of 70 kt already in place. Another item of note is with dewpoints approaching 60+ degree values and HREF showing 0.1 km SRH moving in later this afternoon evening, one can`t rule out the potential for a tornado to occur this evening. However, all of this will be dependent on winds becoming southeasterly, which while latest HRRR guidance has that occurring around 21z, any more of a delay may vastly limit our severe weather potential. Or at the very least, decrease the area extent of severe storm potential, and really keep it more focused to just Powder River and Carter counties. On Monday, a strong cold front will pass through and bring yet again another shot of severe storms to far SE MT. Better confidence to see southeasterly winds and increased instability there, and ample shear will still be present. Instability Will be confided to far SE MT though as downslope flow will be across much of south-central MT. So although still a small spatial area... large hail, damaging winds, and heavy rain will all again be possible with those storms. IMPACTS... With regards to hydro, please check existing flood watches and warnings for localized impacts. WIth regards to thunderstorms, a worse case scenario can expect to see hail above 2+" inches in diameter to occur in far SE MT, and winds gusting 60-70 mph, all on top of the small chance for a tornado to occur with any storm down there as well. While storms should be moving at a moderate speed, PWATs around an inch will bring about heavy rain with each storm as well. Vertz Tuesday through Sunday... Snow/snow showers continue across mountains on Tuesday (mainly for elevations above 8000 ft), then very windy conditions are expected across the region on Wednesday as low pressure deepens over southern Saskatchewan. West/northwest winds gusts of 45 to 55 mph are possible. Tuesday`s highest winds will be more focused in the foothills west of Billings, with widespread high winds expected on Wednesday. Then ridging builds in Thursday into Friday with temperatures quickly warming. WPC clusters continue to show good agreement building the ridge into the region Friday into Saturday, but now the members (cluster 4) which favors the Canadian, suggests and even stronger ridge. So, confidence remains high that we will see highs climbe well into the 90s on Friday across the plains, 70s to 60s in the mountains. Saturday looks to be another warm day with highs in the 90 over the plains, but there is some uncertainty regarding the timing of a cold front and the when the ridge shifts east. A trough then swings through late Saturday into Sunday cooling highs back into the 80s and bringing chances for showers and thunderstorms. Wetenkamp/Vertz && .AVIATION... Showers and embedded thunderstorms with local MVFR/IFR will continue tonight and Monday. Mountains will be frequently obscured. West winds will gust 20-30 knots along the western foothills tomorrow afternoon. JKL && .PRELIMINARY POINT TEMP/POPS... Mon Tue Wed Thu Fri Sat Sun ----------------------------------------------------------- BIL 056/070 047/065 046/073 048/084 055/098 065/095 060/083 83/T 22/W 10/N 00/U 00/U 11/B 34/T LVM 049/062 039/059 040/068 044/081 052/091 058/086 053/076 98/T 63/W 30/N 00/U 00/U 12/T 45/T HDN 056/073 046/066 045/073 046/084 055/100 062/095 060/085 84/T 32/W 10/N 00/U 00/U 11/B 33/T MLS 057/074 049/064 048/068 051/080 059/096 067/095 064/082 +6/T 32/W 21/N 00/U 00/U 00/B 22/T 4BQ 057/076 049/064 045/069 050/079 058/096 070/095 065/085 66/T 63/T 11/N 00/U 00/U 10/U 22/T BHK 057/075 049/063 045/065 050/076 055/089 065/093 063/083 86/T 53/W 11/N 00/U 00/N 10/U 22/T SHR 054/074 043/066 041/072 046/083 057/098 064/093 060/083 57/T 63/T 10/U 00/U 00/U 11/B 33/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...Flash Flood Watch in effect through Monday morning FOR ZONES 56-139. WY...None. && $$
Area Forecast Discussion
National Weather Service Duluth MN
734 PM CDT Sun Jun 12 2022 .DISCUSSION...(This evening through Saturday) Issued at 354 PM CDT Sun Jun 12 2022 Summary: A stalled out warm front across western MN is helping to fire off a few storms this afternoon. Some of these storms may be strong to severe with hail, and damaging winds being the main threats. Model guidance suggests that an MCS will form in the Northern Plains overnight and push east impacting Brainerd Lakes Monday morning. These storms will also have the potential to be severe. Showers and storms will spread east through the morning and early afternoon with the severe risk decreasing the closer they get to Lake Superior. A brief warming period going into Tuesday with some areas climbing into the 80s and 90s, cooler temperatures will still be around the Lake. A warm front is currently stalling out over southwest MN with some showers extending into the Brainerd Lakes and into NW WI. A few lightning strikes have been observed with these cells but as they move further west they are running into more stable air provided by Lake Superior. As we head into this evening we will maintain a weak inversion in the lower levels and some weak MUCAPE values. The frontal boundary is expected to stay outside of our CWA but some storms may be able to fire off to our west and cross into our western counties this evening. Strong shear but weak instability looks to favor some elevated convection with damaging winds and hail being the main threat. SPC has a marginal threat encompassing our western half of counties. The best timeframe for severe still looks to be in the afternoon and evening hours. The further east storms move the stronger the stability they will run into, likely to leading to just general thunder and showers overnight for the eastern half of our counties. Monday morning the severe threat returns. A low pressure system is expected to eject out of the Northern Plains moving east. The 12Z suite of deterministic models still show some variations on the Lows path which will greatly impact how the storms evolve. There is fairly good consensus on the storms initiating tonight over the Red River Valley and possibly forming an MCS as it approaches north central MN. If the low manages to trek further into northern MN then we will see a stronger response in the low level jet ahead of the system promoting heavier rainfall and stronger storms. The HRRR in particular is signaling a bowing line moving through Brainerd and into NW WI in the morning hours. SPC has increased this threat to slight. Additionally, this system could be quite a super soaker. Both the NAEFS and GEFS show a signal for PW above the 99.5 percentile of climatology. This lines up well with the ALPW showcasing a stream of mid level moisture being advected across CA and into the Northern Plains. When this combines with the low level influx of Gulf moisture lingering over the Midwest we may see localized rain totals in excess of 1.5 inches stretching from the Brainerd Lakes to Washburn County. By the afternoon the mid levels begin to quickly warm and may end up capping off storms from firing off once again. Overnight a shortwave rotating through the pattern may be enough to ignite some strong to severe storms. The region is going to see a warming trend as we head into Tuesday. However, strong easterly winds off of Lake Superior should keep things a bit cooler. This forecast package has trended those temperatures slightly cooler to account for the Lake, additionally, we introduced the potential for lingering fog over the Twin Ports and into the low lying areas of Carlton and Douglas. The mix of warm air clashing with the cool Lake should be a good set up for long lasting fog. A cold front will move through Tuesday night with highs dropping back into the 70s and 80s for Wednesday. There is another chance for showers and rain Wednesday as well with a surface low moving out of the Central Plains towards the Great Lakes. It`s too soon to make a call on the severe weather potential with this system given the high degree of differences among the thermal profiles. For now, NW WI has the better odds of seeing rainfall out of this system. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 734 PM CDT Sun Jun 12 2022 Showers and a few thunderstorms over far northern Minnesota in the vicinity of KINL and perhaps also KHIB are expected to dissipate over the next few hours, but showers may linger overnight, mainly over northern MN. Showers and storms overnight may bring a short period of IFR conditions. Another round of showers and storms are expected to move into the area after 10z, which are also expected to bring a period of IFR or even LIFR conditions to the terminals through the morning and early afternoon, with conditions returning to VFR after 20z. && .MARINE... Issued at 354 PM CDT Sun Jun 12 2022 Northeast winds of 10 to 15 kts with gusts of 20 kts will continue through this evening. Overnight, there is a chance for some showers and thunderstorms. Tomorrow morning, models suggest an MCS moving in from the Northern Plains. If these cells manage to hold together they will likely enter Western Lake Superior by late morning. Additionally, winds are expected to increase out of northwest Monday a Small Craft Advisory has been issued beginning Monday afternoon. && .PRELIMINARY POINT TEMPS/POPS... DLH 50 60 53 76 / 60 60 30 20 INL 56 71 58 85 / 50 40 40 30 BRD 63 74 64 91 / 60 70 20 10 HYR 58 73 62 93 / 30 60 20 10 ASX 50 66 55 91 / 50 60 20 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Small Craft Advisory from 2 PM Monday to 5 PM CDT Tuesday for LSZ140>146-150. && $$ DISCUSSION...Britt AVIATION...LE MARINE...Britt
Area Forecast Discussion
National Weather Service Des Moines IA
1102 PM CDT Sun Jun 12 2022 ...Updated for the 06z Aviation Discussion... .DISCUSSION.../Tonight through Sunday/ Issued at 241 PM CDT Sun Jun 12 2022 Take Home Points: *Storm chances overnight, mainly north *HOT and HUMID conditions settling in Mon/Tue *Storm chances Tue night into Wed *Summer appears to have arrived Discussion: Today/Tonight through Tuesday... A weakening upper level wave and weak boundary draped across the state this morning from NW to SE allowed for some lingering showers, which had all but diminished by late morning. By early this afternoon primarily high clouds remained over southern Iowa, remnants from vigorous morning convection, and fair weather cumulus to the NE where mixing and temp/dew point spreads were more favorable. With fairly humid conditions already in place, today has been a "warm" preview of the next couple of days. Broad ridging continues to slide into the Midwest/Plains as troughing digs into the PNW and exits the Great Lakes region. Gradually increasing low-mid level flow will continue to advect in increasing 850mb temperatures, especially in the overnight hours. More on that in a moment though. Model guidance, synoptic and CAMs, have remained consistent in a pair of shortwaves topping the ridge helping initiate strong/severe storms in western Nebraska and Dakotas late this afternoon and evening. Consistency also remains in MCW development with the environment ahead pretty favorable. The main question, as it pertains to Iowa, is whether or not that activity will carry into Iowa? CAM guidance has consistently suggested the Nebraska cluster to weaken/decay as it approaches/crosses the Missouri River, where as the Dakotas cluster will be in more favorable flow/support for MCS propagation. That said, IF the Nebraska cluster can maintain some strength, it will be moving into Iowa at a time when MUCAPE values will be around 1500-2000 J/kg. Again, overall flow is not as supportive as further north into Dakotas/Minnesota, but the chance/threat cannot be wholly dismissed. In fact, 17z/18z HRRR runs have actually trended upwards for said Nebraska cluster in/around the Missouri River. For the time being, have not made large changes to PoPs, but may need to be revisited this evening by following shift. Now back to the heat... Expectation for widespread mid-upper 20s deg C 850mb temps remains, as well as a shot at low 30s deg C in the SW Monday. Fortunately, mixing depth is not expected to be able to tap into its full potential with combination of initial cloud cover and gradually increasing surface flow. Regardless, Mid to upper 90s deg F highs across the SW half or so of the state are forecast. Dew points in the lower 70s deg F pile on to yield heat index values in the 100 to 105+ deg F range. Overnight conditions are not much better with lows only in the mid to upper 70s deg F anticipated. The ridge and peak 850mb temps begin to exit eastward Tuesday, but stronger surface flow and deeper mixing will yield another day in the mid to upper 90s deg F for many. The deeper mixing should also keep dew points a few degrees cooler than Monday, placing heat index values in the upper 90s to near 105 deg F range. All that said, should surprise no one that a heat advisory is in place for a large portion of the CWA and state from Monday afternoon through Tuesday. Have carried the advisory overnight Monday due to the mid-upper 70s deg F lows, which would be detrimental to those without access to AC. Kept the advisory area simple, Highway 20 and south, but note that the NE and NW portions of the advisory are borderline on Monday and Tuesday respectively. Either way, it is the first real hot conditions of the year. Additionally, a few records, both High Temperatures and High Minimum Temperatures may be at risk, including the following at our major climate sites: Monday Highs: Lamoni (95, 1963) Ottumwa (98, 1987) Monday Night Max Mins: Des Moines (75, 1994) Waterloo (75, 1994) Mason City (73, 1994) Ottumwa (77, 1981) Tuesday Highs: Lamoni (99, 1987) Ottumwa (96, 1987) Wednesday through rest of forecast... Some degree of temperature relief is seen as the thermal ridge exits eastward and a cool front enters the state Tuesday night. The front, along with the LLJ, will be the focus for storm development Tuesday overnight and then again Wednesday afternoon/evening. The strong/severe threat appears best Wednesday afternoon/evening with potentially substantial instability ahead of the front, versus Tuesday night when a hydro risk may the greatest concern. Largely zonal flow through the middle CONUS will moderate temperatures a bit, yielding highs mainly in the 80s, but that bit of relief may be short lived with a highly amplified pattern and ridge overhead expected late week into next weekend. What that may mean for the area is another push/round of heat and dry conditions. && .AVIATION.../For the 06Z TAFS through 06Z Monday night/ Issued at 1102 PM CDT Sun Jun 12 2022 VFR conditions will deteriorate into MVFR with pockets of IFR cigs as showers and thunderstorms move through the area, especially in northern terminals (FOD, MCW, ALO). Still low confidence in precip reaching DSM and OTM. Patchy fog possible at all terminals. Precip will begin to taper off by mid to late morning with increasing gusts over 20kts. Low level wind shear will increase after sunset across DSM and OTM with northward expansion beyond the current period. && .DMX WATCHES/WARNINGS/ADVISORIES... Heat Advisory from noon Monday to 7 PM CDT Tuesday for IAZ023- 033>039-044>050-057>062-070>075-081>086-092>097. && $$ DISCUSSION...Curtis AVIATION...Hagenhoff/Jimenez
Area Forecast Discussion
National Weather Service Goodland KS
1005 PM MDT Sun Jun 12 2022 .UPDATE... Issued at 730 PM MDT Sun Jun 12 2022 Two severe thunderstorm watches are in effect, one for our northern counties and another for our southern. Storms are just now entering far eastern Colorado and are approaching an instability axis extending from near Yuma to Tribune. Its anticipated that once the storms cross the axis they should become strong to potentially severe. The second area of storms over Leoti are presently producing wind gusts to 56 mph. They are expected to continue to the northeast skirting our southern forecast area through Hill City. These too are expected to be strong to severe. 00Z HRRR is again showing heat burst potential on the outflow as temperatures rise into the lower 90s and relative humidity falls into the teens, similar to last night. Locally researched blowing dust parameters from the 18z NAM favor some blowing dust across both severe thunderstorm watch areas through this evening. Otherwise, have let the Heat Advisory expire for all but Graham and Norton counties where it continues overnight through Monday. && .SHORT TERM...(This evening through Wednesday) Issued at 230 PM MDT Sun Jun 12 2022 Convection has initiated this afternoon near the Front Range in response to a shortwave trough moving out of the central Rockies. Storms will be moving into an increasing unstable environment towards northwest Kansas and southwest Nebraska. In addition, a frontal boundary has settled near the Kansas and Colorado border area which may serve as an additional focus for initiation or enhancement. All in all, latest HRRR and NAMNEST show that northwest portion of the area and into southwest Nebraska will have the best chances for thunderstorms through about 06z. Large hail and damaging winds will be the primary hazards, but with deep layer shear at around 30-35kts cannot completely rule out a supercell and attendant risk of a tornado, but probability is low. Low temperatures tonight will be in the 60s and 70s. Monday will be very hot and windy with high temperatures well into the 100s and southwest winds gusting generally 40-45 mph, though do see up to 60 mph in the deeply mixed forecast soundings of western portion of the area. Another shortwave trough in the southwest flow aloft may trigger scattered thunderstorms along a subtle surface boundary in the afternoon and evening, roughly along a Norton to Tribune line. Low CAPE/inverted-V forecast soundings in those areas suggest the possibility of damaging wind gusts near stronger storms. Cold front will then move through the area late Monday night and into Tuesday morning. Lows will range from the upper 50s behind the front in northeast Colorado to the middle 70s ahead of it in Hill City. On Tuesday models show front possibly stalling out across the southern forecast area in the afternoon, though the ECMWF does have it south of the area. High temperatures will range from the upper 80s in Colorado to the middle 90s in southern areas due to later frontal passage. Precipitation chances should hold off until Tuesday night with best chances across eastern and northeastern areas. Surface instability appears to stay south of the area ahead of the front, however elevated instability does develop Tuesday night with MUCAPE up to 1500 j/kg. Lift may also be enhanced by the presence of a 50-55kt low level jet at around 750 mb. Set up suggests a few storms may be capable of producing large hail through about 06z before the MUCAPE begins to diminish. Low temperatures will be closer to normal, even slightly below normal, ranging from the lower 50s to lower 60s. Set up for Wednesday not that different than Tuesday. Front stalled out just south of the area with post frontal upslope flow in the forecast area. Temperatures will be slightly above normal with highs in the upper 80s. Another shortwave trough moves through Wednesday night. However, unlike Tuesday night MUCAPE stays just out of the area and there is no low level jet. Nonetheless, may see a few storms develop in those southern areas near the front Wednesday night with some weak isentropic lift around 700mb, but most areas will be dry. Low temperatures will be in the 50s and 60s. .LONG TERM...(Thursday through Sunday) Issued at 132 PM MDT Sun Jun 12 2022 Hot and dry conditions will highlight the period beyond mid-week next week and into next weekend. The upper ridge amplifying over the Intermountain region between low pressure systems moves over the Rockies and High Plains region Thursday and Thursday night as high pressure across the southern United States expands across the plains and becomes part of the ridge of high pressure over the central U.S. as it extends northward into south central Canada on Friday and Friday night. the upper ridge moves slowly eastward into position over the eastern Plains states and Mississippi Valley regions through next weekend. Surface high pressure will expand across the Plains states through Saturday with a trough of lower pressure deepening along the front range that begins pushing east over the northern plains and extends southward through the central and southern high plains ahead of the main upper trough approaching from the west. With high pressure at the surface and aloft, expect dry conditions and warming temperatures, especially into next weekend as persistent southwest surface flow assists in producing hot temperatures and dry conditions. Relative humidity values will be low enough through next weekend that even though ambient air temperatures are expected to be in the lower 100s across a good portion of the area, Heat Index values will remain in the 90s. Therefore, there does not appear to be a need for Heat related products late next week into the weekend. Looking a little further ahead, by Sunday night into early Monday morning, there may be a chance for thunderstorms moving in from the west as the surface trough and trough aloft move into the western sections of the forecast area. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1005 PM MDT Sun Jun 12 2022 KGLD...VFR conditions are expected through the period. South winds up to 11kts at taf issuance will continue through sunrise then increase from the southwest with gusts up to 40kts during the day Monday. South winds gusting up to 25kts or so are expected Monday evening. KMCK...VFR conditions are expected through the period. An east wind around 10kts at taf issuance will quickly become light and variable through the remainder of the night. On Monday, southwest winds increase through the day, peaking around 40kts in the afternoon. South winds gusting to 25kts or so are expected Monday evening. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Heat Advisory until 7 PM CDT Monday for KSZ004-016. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...024 LONG TERM...LOCKHART AVIATION...99
Area Forecast Discussion
National Weather Service Grand Rapids MI
751 PM EDT Sun Jun 12 2022 LATEST UPDATE... Aviation .DISCUSSION...(This evening through next Sunday) Issued at 338 PM EDT Sun Jun 12 2022 -- Squall line potential Monday afternoon and evening -- Most of the focus of the forecast is on tomorrow afternoon and evening. Models continue to produce a squall line that sweeps from west to east across portions of the forecast area Monday likely between the hours of 200pm and 800pm. SPC continues to have portions of the area in a slight risk for severe weather associated with a bowing squall line. The upper level wave responsible for our storms tomorrow is in Colorado at this time. It moves into the plains this evening and reaches Southern Minnesota by Monday morning at 800am. We will be able to monitor the approach of the squall line as it will likely stay together in some fashion from Minnesota as it works east towards Lake Michigan through the course of Monday morning. There remains some uncertainty as to the exact timing and location, but all of the higher resolution models have the signal in some fashion. The HREF 4hr max reflectivity has the first approach to the lake at 100pm on the Wisconsin side. Higher reflectivity continues over the lake and into Western Lower Michigan into the afternoon and evening as different members of the HREF have slightly different timing. The HRRR is a bit later in timing. The concerning factors for a squall line with damaging winds are related to the wind fields in place. The first item that jumps out is the strength of the mid level winds. The NAM12 has 70 knot winds at 500mb`s Monday evening near MKG. 30-40 knot 850mb level winds are noted around the same time. Our stronger wind events usually always have stronger wind fields in place in both the low and mid levels and this event is no exception. The CAPE field just off to the south that noses in during the afternoon should be at least in the moderate category. The northern edge of this will be bounded by the warm front and that will likely be into the GRR forecast area at the time of the squall line will be moving through. The system will likely have a MCV associated with it given it will be a long live system originating tonight in the plains. So, winds will be the primary severe weather threat, but hail and a few tornadoes cannot be ruled out given good forcing. Tornadoes would be of the fast spin up QLCS variety. Bottom line... possibility of some higher end wind gusts Monday afternoon and evening associated with a squall line. Large hail and tornadoes are both a non zero threat as well. -- Heat is still on for Tuesday and Wednesday -- +24 to +26C air moving into Western Lower Michigan at 800pm on Tuesday is some of the warmest 850mb temps I have seen in my years at GRR. The ECMWF MOS max temp on Wednesday has gone to 94. The deterministic ECMWF temps may be a bit high, but are totally within the realm of possibilities in the mid to upper 90s both Tuesday and Wednesday. So, we could be looking at power outages going into Tuesday which will be into the teeth of two days of heat. Heat advisories are possible both days. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 750 PM EDT Sun Jun 12 2022 VFR conditions will prevail overnight and into Monday afternoon. There could be some shallow ground fog late tonight but this was left out of the forecast since it should be transient. Thunderstorms are possible late Monday afternoon, but coverage should be greater around and after 00Z Tuesday when a squall line with large hail and winds greater than 50 knots is possible. Refer to later forecasts and discussions for specifics on the potential for severe storms Tuesday evening. && .MARINE... Issued at 338 PM EDT Sun Jun 12 2022 We expect no advisory level wind or waves tonight through Monday in terms of the gradient/synoptic scale variety. We do have the potential for a squall line Monday afternoon and evening. This wind will be of the short term variety and is expected some time between 200pm and 800pm over southern portions of the lake most likely. If the line is moving at a higher rate of speed, which it looks like it will be in the higher resolution models, it will have the potential to produce a seiche or meteotsunami. The two phenomenon are different processes and are dependent on the pressure setup with the squall line. We will be monitoring the speed of the line tomorrow, higher speeds (40-60+ knot movement) favor the formation of a meteotsunami. Tuesday night into Wednesday night south-southwest winds will be on the increase in the warm sector and we may approach or attain advisory level winds and waves. The main concern would be for Wednesday night into Thursday morning as 35 knot winds are noted Wednesday night at 1,000 feet. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...None. && $$ DISCUSSION...Duke AVIATION...Ostuno MARINE...Duke
National Weather Service Jackson KY
946 PM EDT Sun Jun 12 2022 .UPDATE... Issued at 940 PM EDT SUN JUN 12 2022 Latest RAP analysis shows a subtle shortwave moving through the area which appears to be providing just enough support to touch off some widely scattered light rain showers. Adjusted PoPs to have a slight chance across much of the area this evening, and continuing through the overnight with some isolated thunder possible. Additional adjustments will likely be needed after the 00Z data comes in. Updates sent to NDFD and web servers. UPDATE Issued at 725 PM EDT SUN JUN 12 2022 Freshened up the grids with the latest obs. Made some slight adjustments to PoPs this evening, along with sky cover. Updates sent to NDFD and web servers. && .SHORT TERM...(This evening through Monday night) Issued at 355 PM EDT SUN JUN 12 2022 Light rain showers are continuing to stream across the northern periphery of the CWA. Any convective storms look to remain well to the north and west of the region at least through the remainder of the afternoon. Cloud cover has filtered back over the area, which has leveled out temperatures in the mid to upper 80s in the southwest, and in the low to mid 80s across the rest of eastern Kentucky. The main synoptic feature affecting the region is the broadening upper ridge centered over the south Central and Gulf States. The influx of rising height values will aid the influx of unsavory heat and humidity into the Ohio Valley, especially towards the latter half of Monday into Tuesday as the ridge axis moves to directly to the south of the area. Dew points rise from the mid to upper 60s tonight through early Monday, to the low to mid 70s by Monday evening into Monday night. Despite the increase in low level moisture and instability, the weaker forcing over the area should cause most overnight convection to be north or south of the CWA. Some of the CAM`s feature a weak wave progressing southwestward from southern Indiana early Monday morning through early Monday afternoon. For that reason, the 20-30 POPs were kept for the majority of the daytime hours. If storms were to develop, they could be strong to severe, but the chances are conditional. Low temperatures tonight and tomorrow night are quite mild, only dropping into the upper 60s to low 70s; and with the increased cloud cover, the ridge/valley split potential is quite limited. Highs Monday will rise into the upper 80s to low 90s with heat index values peaking in the upper 90s. .LONG TERM...(Tuesday through Sunday) Issued at 315 PM EDT SUN JUN 12 2022 The story in the extended remains much the same. An amplified trough/ridge/trough pattern is expected to set up and remain in places across the CONUS. A strong ridge situated over the Great Lakes and the Ohio and Tennessee Valley regions will bring much warmer and muggy weather to eastern Kentucky. Conditions Tuesday and Wednesday are still quite favorable for record, or near record setting, temperatures around the area. Strong daytime heating and subsidence beneath the ridge should allow things to really heat up for the middle of the week. As for precipitation chances, they will hinge on whether or not our forecast area is more firmly entrenched on the down stream side of the upper ridge axis. If we are more directly beneath the ridge, we can expect hot and muggy weather around the area, but little in the way of rain, as any showers and storms would be shunted off to our north and northeast. However, if the ridge axis shifts more to our west, then we could see increased chances for rain, particularly in our northern and northeastern counties. With this uncertainty coming into play, it was decided to keep Tuesday, Tuesday night, and the first half of Wednesday dry, with increasing rain chances around the area from late Wednesday into the weekend, as the models have the central breaking down a bit and flattening out. This would allow a more southern intrusion of shower and storm activity that would form to our west and northwest. Therefore, the best PoPs in the extended will be from late Wednesday through Friday. Going into the next weekend, it appears that another ridge will settle over the region, and may usher slightly cooler and drier air into the area. Temperatures are expected to be well above average in the extended, especially Tuesday through Friday, when most locations will see highs in the 90s. In fact, highs on Tuesday, Wednesday, and Thursday should be able to reach the low to mid 90s around the area, with a few spots maybe even teasing the upper 90s Tuesday and Wednesday. Nightly lows will range from the upper 60s to lower 70s around the area. All in all, the upcoming work week looks to be hot and steamy with a rain chances possible here and there toward the middle and end of the week. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) ISSUED AT 725 PM EDT SUN JUN 12 2022 VFR conditions to start the 00Z TAF period with mainly SCT high clouds moving across the area. Light and variable winds expected overnight. Some patchy river valley fog is possible but should not impact any of the terminals. Guidance is suggesting MVFR ceilings towards dawn as a frontal boundary sags closer to the area, but confidence is low at this time. SCT showers and isolated thunderstorms are possible late tonight and overnight, however chances are too low for mention at any of the sites, so will handle with amendments as needed. If there are MVFR ceilings in the morning, they should improve back to VFR by late morning and then VFR is expected for the remainder of the period. Winds on Monday will be W/SW around 5 kts. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CMF SHORT TERM...LUEHRS LONG TERM...AR AVIATION...CMF
Area Forecast Discussion
National Weather Service Pocatello ID
941 PM MDT Sun Jun 12 2022 .UPDATE... The heavy rain showers have exited the central mountains so will update to remove the areal flood watch and flash flood watch. River flooding is ongoing in some locations and additional river flood warnings are likely on Monday as the combination of snowmelt and rainfall from this system makes its way down area streams and rivers. Otherwise, forecast update includes minor adjustment to rain chances, amounts and winds for Monday based on 00Z model guidance and evening trends. 13 && .PREV DISCUSSION... /issued 238 PM MDT Sun Jun 12 2022/ SHORT TERM...Tonight through Tue night. A negatively-tilted upper level trough trough has enough entrained moisture and instability to put together a marginal risk of severe thunderstorms and a threat of excessive rainfall for the central Idaho mountains, which, along with the Island Park area, will be bearing the brunt of the heavy rains and general bad weather. During the overnight hours, the available moisture in the air will decrease, but there is still a threat of showers and thunderstorms on Monday as well. The upper level trough will close off and become an upper level low, slowing its eastward progress and thus lingering around the northern rockies for all of Monday. With a northeastward track, by Tue mid-day the low tracks into Canada, reducing the threat for the southern half of the forecast area, but a continuing threat for showers and thunderstorms to the northern half and the ID-WY border. The closed low then rotates a trough through Wed evening which will keep the thunderstorms going Tue evening until late. This trough-turning-into-a-low is also bring strong wind aloft already today and continuing Mon. Local study indicates wind in the entire Snake River plain starting early Mon morning will start reaching 30 mph, with the area growing substantially by afternoon. Gusts to 55 mph area also supported. This low has a number of features going for it: a 100KT jet max aloft over eastern Idaho, strong cold air advection, 500mb and 700mb wind very strong in the morning, a gradient across southern Idaho in excess of 10mb the entire time, and the surface low slowly moving through Montana and Wyoming. Expect this to subside sometime after 14/00Z. The cloud cover will bring afternoon temperatures down strongly, with a 12 to 18 degree drop Sun compared to Sat having already occurred. Expect another 10 to 14 degree F decrease in the afternoon high for Mon. The decreased clouds for Tue means the start of a warming trend, but just a minor start, perhaps up 2 to 8 deg F. Messick LONG TERM...WEDNESDAY THROUGH NEXT SUNDAY... Our sprawling longwave low pressure center finally starts to move east Wed with a shortwave ridge bringing dry conditions Wed/Thu and a STRONG/FAST warming trend. Highs should make a run at 65-70 Wed, then 80-90 Thu, and 85-95 Fri! As the previous forecaster noted, NBM v4.1 probabilities of reaching or exceeding 90F have increased from 24 hours ago, now running at 60-75% from Pocatello through the Burley area and in some of the valleys along the UT border. A fresh low pressure system is forecast to bring a renewed chance for showers/t-storms starting Fri eve and continuing into the weekend, with much cooler temps again for the weekend as well. WPC 500mb height cluster analysis suggests some forecast uncertainty with the exact timing of this system, which will ultimately determine whether or not we will squeak out a third consecutive dry day Fri. 01 AVIATION... Few overall changes were made to the TAFs with the 18z/noon package...utilized the latest high-res CAMs to refine start time for VCTS this afternoon (generally 20-21z/2-3pm) as well as end time. Continued to hold predominant cigs at VFR...cannot rule out brief dips to MVFR in t-storms along with gusty/erratic winds over 40kts and small hail, but will need to watch radar trends for any potential direct hits to a TAF terminal and amend accordingly. Degree of destabilization/instability is the main limiting factor today for sev && .SHORT TERM... .LONG TERM... && .AVIATION...ere t-storms with KBYI, KPIH, KIDA, and KDIJ all sitting right along the edge of better clearing to the SE where instability may end up being greatest. Watch for a SW crosswind at KSUN this afternoon/eve. Regional winds should generally be WSW at the Snake Plain terminals this afternoon/eve (KBYI, KPIH, KIDA), but VWPs are a bit messy with some suggestion of a period of NNW winds, and the HRRR is super contaminated with convective outflows, so confidence in wind trends today is low with potential for winds to get pretty variable depending on how t-storms evolve. -SHRA or -RA linger overnight tonight from the Snake Plain south/east, as regional winds start to ramp up once again by 08z/2am with an additional increasing trend after sunrise. Can`t rule out some additional isolated showers/t-storms Mon afternoon for all terminals except KBYI, but biggest impact should be the winds potentially exceeding 20g35kts out of the WSW through just after sunset. As usual, KSUN and KDIJ will remain a bit more sheltered. 01 HYDROLOGY...The moist air mass has brought the potential for flash flooding if thunderstorms develop this evening, with only some partial lowering of the moisture content overnight and Monday. The moderate to heavy rain that has fallen already, as much as one inch already today, will also increase snow melt. This combination has led to areal flood watches and flash flood watches in the central Idaho mountains, and main stem river flood warnings for the Big Wood River at Hailey and the Big Lost River at Howell Ranch (near Chilly). Minor flood stage is expected to be reached during the overnight hours, plus or minus an hour from midnight. With the additional rainfall possible Monday, do not expect a drop below flood stage until Tuesday morning at the earliest. Messick && .PIH WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 6 AM to 9 PM MDT Monday for IDZ051>055. && $$
Area Forecast Discussion
National Weather Service Sacramento CA
129 PM PDT Sun Jun 12 2022 .Synopsis... Showers and thunderstorms ending this evening. Breezy north and east winds develop early this week with low RH and elevated fire weather concerns. Warming trend into the middle of the week. && .Discussion... HRRR and High Resolution short term ensemble models did good job with convection today in northern Sacramento Valley. Strong cell with very heavy rain (0.50" in Red Bluff in 15 min) has since decreased. Will still be risk of a few more organized cells through early this evening. Upper trough that caused this activity will be east of the area Monday. Behind it still expecting some gusty northerly winds. No doubt where it did rain will help with fuels but overall thinking is strength of winds and fuel status should keep us under a critical fire weather situaiton...but definately at least elevated concerns with lower RH and the north winds. Winds on Tuesday should not be as bad. Wednesday upper level ridge builds in pretty good with hot temperaures returning in the mid to upper 90s. Very good agreement in ensembles and clustering for this scenario. Rasch && .EXTENDED DISCUSSION (Thursday THROUGH Sunday)... Ensemble in good agreement that another trough will move to west coast by this weekend. Cooling from this will begin on Thursday. System is pretty dry but also pretty deep for this time of the year again. Agree with NBM solution of slight chances across the north and higher terrain as cold pool aloft should cause some instablity. Over impacts from it looking prety minimal though. Perhaps biggest concern will be winds at higher elevations but fuels still holding good in those area as of right now. Rasch && .AVIATION... VFR conditions next 24 hours, except local MVFR conditions vicinity scattered showers northern Sacramento Valley and surrounding mountains thru 04Z Monday (isolated thunderstorms possible until 02Z). Areas southwest surface wind gusts 15-30 kts through 06Z, then becoming northerly. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$