Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/08/22


Area Forecast Discussion
National Weather Service Charleston SC
959 PM EDT Wed Sep 7 2022 .SYNOPSIS... A cold front will continue to push offshore tonight before it stalls to the south through the weekend. Another cold front could impact the region around the middle of next week. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... An upper trough will drop slowly through parts of the east and southeast states through the night, causing a cold front that is starting to trickle into the forecast counties, will push offshore overnight and late. Behind the front, high pressure will build out of the Great Lakes and the upper Midwest. The mix of deep moisture convergence, modest MLCAPE and slowly falling heights will allow for activity to persist as it moves further into the local counties. Based on latest trends we initially have 20/30% PoPs early on, then PoPs that are as high as 50-60% over the Charleston tri- county district. We show 20-30% PoPs many other sections, except holding onto a rainfree forecast roughly south of I-16 in Georgia. The bulk of the convection that does occur, happens through about 3 AM, with most activity fading in both coverage thereafter, as the cold front moves through. Some guidance continues hinting at fog late tonight far northwest. But condensation pressure deficits are not that favorable. So no mention in the actual forecasts. There is just enough cool advection that occurs behind the cold front to allow for min temps to get down to 70-75F, with even a few upper 60s in the Francis Marion National Forest. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... At the surface a weak lee trough across the Mid Atlantic will become replaced with high pressure, taking on more of a wedge- type pattern. As an upper ridge axis pushes offshore and becomes highly amplified, an elongated trough with an embedded low will deepen across the northern Gulf/LA coast. The quasi-stationary low will continuously feed shortwave energy into the area, rippling downstream the upper trough. Numerous showers and isolated embedded thunderstorms are expected, bringing rounds of rainfall each day and into the overnight periods. Instability remains extremely limited which should temper deep, if any, convection. In addition, Friday looks especially interesting as models show a hybrid baroclinic/convection type set-up with precipitation taking on more of stratiform nature at times as isentropic lift strengthens. By Saturday, the stationary front will lift northward slightly as a warm front and align itself along the coast. Low-level southeasterly flow will continue overrunning/isentropic upglide through Saturday. Heavy Rain: WPC currently highlights our area in a Day 2/Thursday marginal risk and a Day 3/Friday slight risk for excessive rainfall. General QPF totals are expected to range from 2-4 inches through the period with locally higher amounts possible. HREF probabilities show at least a 40-50% chance of 1 inch of rainfall or greater within a 3-hr period along the coastal areas each 3 hourly block from 5 PM Thursday through 8 AM Friday (which is as far as the current guidance extends). Flood Advisories could be needed in areas that experience a prolonged period of greater rain rates. Also, multiple days of rainfall could weaken soils and trees could become uprooted after long periods of saturated conditions. Temperatures will drop a few degrees Thursday with highs in the mid to upper 80s, lower 80s on Friday, and warming into the mid 80s for Saturday. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... The aforementioned upper low will eventually become absorbed by a secondary low that will slide across the central U.S. This disturbance will provide the ingredients to continue the active weather early next week, but convection coverage should return to more scattered in nature with a diurnal pattern. As the low advances eastward it will help push a cold front across the region Wednesday/mid-week. Rainfall will help moderate temperatures to near-normal through the period. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... KCHS and KJZI: Scattered SHRA and TSRA will be at or near the terminals late this evening and during the first part of the overnight period, until a cold front passes through. Until trends are more certain we prefer to show no more than VCSH and VCTS. However, should a direct impact occur, then flight restrictions would at least temporarily happen during this time. There is small chance of additional flight restrictions late tonight and Thursday morning with moisture trapped behind the cold front. And there could again be some flight restrictions late Thursday when the best moisture convergence occurs in tandem with energy aloft. For now we prefer to show no more than VCTS late in the day. KSAV: In all likelihood the convection upstream will fade before reaching the airfield. Thus we have VFR tonight into Thursday morning. Conditions favor a potential for flight restrictions in SHRA/TSRA Thursday afternoon due to the proximity of the front, energy aloft and strong moisture convergence. For now we have VCTS, but adjustments will be required in later TAF issuances. Extended Aviation Outlook: Periodic flight restrictions in showers and thunderstorms are possible through the weekend. In addition, prolonged low visibilities within heavy downpours are possible. && .MARINE... A backdoor front will slowly drop through the marine area overnight. Winds that begin the night from the SW or W around 15 kt or less, will eventually clock around to the N and NE overnight and late, as high pressure builds behind the front out of the upper Midwest and Great Lakes. Winds could surge out of the N on parts of the AMZ350 waters, although only briefly, as depicted by the HRRR between about 12 AM and 3 AM. Seas will average 2-4 feet, with much of the wave energy in the from of swells that originated from distant Hurricane Earl. Isolated to scattered t-storms, mainly between about 12 and 3 AM and most likely on the South Carolina waters, will occur in response to the cold front. Thursday through Monday: As a cold front stalls to the south of the Georgia waters, winds will shift out of the east/northeast. The majority of the local waters will receive plentiful rainfall through the weekend, where bouts of heavy rain/gusty winds are likely. Outside of any showers and thunderstorms, wind speeds will be less than 15 knots. Seas will average 2-4 feet, although some 5 ft seas will move into the outer Georgia waters Friday into Saturday. Early next week, winds will become more southerly ahead of an approaching front. Rip Currents: Long period swell around 11-12 seconds being generated from distant tropical cyclone Earl combined with onshore winds will lead to an elevated risk of rip currents at all of our beaches through the weekend. The current forecast features a Moderate Risk of Rip currents for all beaches Thursday and a High Risk for all beaches Friday. && .TIDES/COASTAL FLOODING... The combination of the upcoming full moon and onshore winds will lead to elevated tide cycles through the weekend. Coastal Flood Advisories are likely during the evening high tides Thursday and Friday. Additional Coastal Flood Advisories could be needed during the evening high tides through the weekend, especially given any rainfall that coincides with high tide. The risk will be highest along the Charleston and Colleton county coasts, where minor to perhaps moderate coastal flooding will be possible. Further south, tide levels could approach minor flood levels. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM... SHORT TERM...BRM LONG TERM...BRM AVIATION... MARINE... TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Corpus Christi TX
614 PM CDT Wed Sep 7 2022 ...New UPDATE, AVIATION... .UPDATE... Issued at 601 PM CDT Wed Sep 7 2022 Adjusted PoPs for the next few hours to account for current radar trends. Isolated convection will be possible over the next few hours with activity expected to wane with the loss of daytime heating. It`s possible we see activity linger a bit longer than expected as the RAP tugs a H5 vort max along the coast through the evening hours but confidence was not high enough to reflect in the forecast at this time. && .SHORT TERM... (Tonight through Thursday night) Issued at 245 PM CDT Wed Sep 7 2022 Key messages: - Isolated showers and thunderstorms early this evening over the northern CWA becoming isolated to scattered Thursday afternoon. - Dry (rain-free) conditions prevail beginning Thursday night. A band of positive vorticity on the backside of a mid-level low located over Louisiana along with a weak frontal boundary has initiated convection over the Hill Country this afternoon. Latest CAM guidance has this activity pushing southward, diminishing as it reaches our northern CWA. We`ll have to keep a close eye on this activity as recent events have shown that CAM guidance typically underplays the activity of outflow boundary driven convection heading into the evening. Can`t ignore the fact that instability will be decreasing with loss of heating but have included slight chances of showers and thunderstorms over the northern half of the CWA through the evening. Expect all activity to be done by midnight tonight. A shortwave extending from the aforementioned low is projected to send a second band of positive vorticity from 850 to 500mb north to south across South Texas through the afternoon into early evening on Thursday. Models do vary in the strength of this band with the GFS/NAM stronger than the ECMWF. But CAM guidance (HRRR & ARW) is also showing isolated to scattered coverage in the afternoon. Went with 20-30% PoPs across South Texas with greatest chances over the Victoria Crossroads. Highs will generally range near 90 along the coast to the mid 90s over the Rio Grande Plains with lows in the low to mid 70s. && .LONG TERM... (Friday through next Tuesday) Issued at 245 PM CDT Wed Sep 7 2022 A subsident and drier air pattern will be the main story for the long term period. To kickoff things off the upper air pattern will feature an upper trough draped across the eastern CONUS and ridging along west Mexico stretching up into the Desert SW. As we progress through the weekend, not much change for South Texas as expecting dry and warm conditions. Early next week the aforementioned trough becomes embedded in the overall pattern to the north and the ridge expands and shifts eastward. Meanwhile, a mid-level low tracking across the northern Plains will send a front surging southward. Looking at the latest deterministic guidance shows somewhat of a weak boundary approaching our CWA. Even if it does reach our border, not expecting anything more than a shift in the winds. PWAT`s are progged to dip to near a low of around 1.20" this weekend which is less than the 25th percentile for this time of year. Rain chances do increase slightly towards the middle of next week as precipitable water values increase closer to 1.50" combined with the seabreeze. Afternoon temperatures during the long term period will be mainly persistent, ranging from the upper 80s to the mid 90s. Meanwhile overnight lows will range in the 70s. Maximum heat indices will top out near 100 degrees across portions of South Texas through the middle of next week. && .AVIATION... (00Z TAFS) Issued at 601 PM CDT Wed Sep 7 2022 VFR conditions are currently in place across the region. Isolated showers and thunderstorms are currently ongoing north of the region and may impact COT and VCT from 00Z-04Z. As a result, introduced VCTS for the next few hours. Otherwise, there will be a brief window closer to sunrise where we may see some patchy MVFR fog across ALI/VCT with VFR returning by mid morning. Winds will be light and variable through the period. && .MARINE... Issued at 245 PM CDT Wed Sep 7 2022 Isolated showers this afternoon will diminish by early this evening. Isolated to scattered showers and thunderstorms redevelop late overnight tonight continuing through midday Thursday before diminishing later in the afternoon. Generally weak and variable flow will persist through early next week Isolated showers and thunderstorms are possible on Friday then drier for the weekend. Isolated thunderstorm chances return early next week. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 74 93 74 90 / 10 20 20 10 Victoria 72 93 72 92 / 20 30 20 10 Laredo 75 94 75 94 / 10 20 20 10 Alice 73 93 72 94 / 10 20 20 10 Rockport 76 92 77 91 / 10 30 20 20 Cotulla 75 97 75 97 / 20 10 10 10 Kingsville 73 92 73 91 / 10 20 20 10 Navy Corpus 77 92 78 89 / 10 20 20 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ SHORT TERM...EMF LONG TERM....BF AVIATION...TC/95
Area Forecast Discussion
National Weather Service Dodge City KS
535 PM CDT Wed Sep 7 2022 ...Updated Aviation Discussion... .SHORT TERM...(This afternoon through Thursday night) Issued at 1200 PM CDT Wed Sep 7 2022 Impressively strong and expansive midlevel high (near 600 dm) was near its peak intensity, centered over Utah at midday. Strong subsidence on the anticyclone`s eastern periphery continued to produce a clear sky across all of the Great Plains. High pressure aloft will begin collapsing Thursday, with appreciable height falls over SW KS. Despite this evolution, models show little change in 850 mb thermal fields, and the upper 90s expected Wednesday afternoon will be repeated Thursday afternoon. A few locations will flirt with 100 degrees today and/or Thursday. Sky grids will remain at 0% through Thursday as the weakening ridge axis remains overhead. Dry air will continue to promote large diurnal temperature ranges, with upper 50s and lower 60s at sunrise, and upper 90s to near 100 at 4 pm. Light winds will continue this afternoon, tonight and early Thursday. After 10 am Thursday, S/SE winds will increase some to 10-20 mph, gusting to 25 mph, in response to 995 mb lee cyclogenesis over NE Colorado. As shown by HRRR vertically integrated smoke forecasts, smoke will continue to be imported over SW KS through Thursday, transported by the northerly midlevel flow on the eastern periphery of the weakening upper high. The sky will appear hazy at times, but did not attempt to account for this in sky grids. Since most of the smoke will be well above the boundary layer, did not include smoke in the weather grids. .LONG TERM...(Friday through Wednesday) Issued at 153 PM CDT Wed Sep 7 2022 Much advertised cold front continues to be forecast to be entering NW Kansas during the day Friday. The cold front boundary is expected to collide with a very hot boundary layer over western Kansas Friday, which is expected to temporarily slow its southward progression. As such, Friday will be another very hot day, with afternoon temperatures well into the upper 90s across the central and southeast zones. Increased the NBM max temp grid several degrees. Prefer the fastest guidance regarding cold front progression, with the front accelerating through SW KS after sunset Friday evening. Given 12z NAM`s progged pressure gradient Friday evening, north winds will be strong and gusty during this time, stronger than NBM or other guidance. Expecting the cold front to clear the Oklahoma border by sunrise Saturday. Saturday will feature a welcome taste of fall, with increasing clouds, elevated north winds by afternoon, and much cooler temperatures. Northern zones will be reduced to the 70s Saturday afternoon. Models project shower and isolated thunderstorm coverage to increase Saturday afternoon, as moisture and lift increase over the incoming cool airmass. The best window of opportunity for sorely needed rainfall is focused on Saturday evening, when a frontogenetic band of showers is expected in the post frontal environment. NBM pops align with this thinking, but again purposely kept pops contained to the chance category (40-50%) given expectations in an exceptional drought. Ensemble average/12z ECMWF QPF is around 0.25 inch, and this appears to be a reasonable expectation for some locations Saturday evening. It won`t be much, but it is the only chance of rain in the forecast. North winds may be at their strongest as the rain falls, as 1028 mb surface high pressure builds south into NE Colorado Saturday night. Surface high pressure will build in strongly Sunday, with a clearing sky, light winds and wonderful temperatures. Sunday afternoon will present some of the nicest weather of the year with lower to mid 70s and light winds. Surface ridge is forecast to hold through sunrise Monday, allowing for radiational cooling with light winds, dry air, dry ground and a clear sky. Upper 40s are expected to be common Monday morning. High pressure ridging aloft builds in strongly Monday through Wednesday, with a rapid warming trend and no chance of rain. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 532 PM CDT Wed Sep 7 2022 VFR conditions for the entirety of the period for all TAF sites. Light south winds less than 10kts and clear skies overnight. Winds will increase out of the south after 15Z to 25kt gusts due to tightening of the gradient with leeside troughing deepening over eastern Colorado with more difluent northwest flow aloft. This will last through the end of the period before diminishing towards sunset due to radiational cooling. No other weather elements are expected at this time. && .PRELIMINARY POINT TEMPS/POPS... DDC 62 98 63 98 / 0 0 0 0 GCK 60 97 63 93 / 0 0 0 10 EHA 60 99 62 94 / 0 0 0 0 LBL 61 98 63 97 / 0 0 0 0 HYS 62 97 63 93 / 0 0 0 10 P28 63 98 61 98 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Turner LONG TERM...Turner AVIATION...Lowe
Area Forecast Discussion
National Weather Service Duluth MN
627 PM CDT Wed Sep 7 2022 .DISCUSSION...(This evening through Tuesday) Issued at 314 PM CDT Wed Sep 7 2022 Summary: Very warm temperatures are forecast Thursday with a chance for thunderstorms late Thursday into Thursday night as a cold front moves into the region. The front will move slow with chances for showers/storms lingering into the weekend over portions of the Northland. Much cooler temperatures arrive Friday. Drier conditions expected for most late weekend into mid-week. High pressure will move south and east of the region tonight leading to mostly clear skies. The pressure gradient will strengthen tonight between the departing high and low pressure off to the west and northwest. Strong warm air advection will occur tonight into Thursday driving highs to 80 to 90 degrees Thursday afternoon. Smoke should be on the increase tonight into Thursday which may temper highs some. Gusty southerly winds will occur ahead of the front Thursday with gusts of 25 to 35 mph. The strong warm air advection will lead to a strong cap as seen on forecast RAP soundings. We delayed shower/storm chances until late afternoon/early evening as it should take some time for the cap to weaken and it may not occur until later Thursday evening as the upper trough gets closer. Mid to upper sixties dewpoints won`t have far to go to get into the Northland as they were over central to southern Minnesota this afternoon. The RAP forecasts a zone of MLCAPE values from 1000 to around 1500 J/KG ahead of the front with surface dewpoints of 65-70 degrees, which are likely to occur. Deep layer shear will be favorable for organized severe storms once the cap weakens, the question is just when will it weaken. It`s possible some elevated storms may develop first Thursday afternoon but there is still decent CIN present for that. 700-500MB lapse rates will increase to 9 C/KM ahead of the front so large hail, greater than ping pong ball size, and damaging winds will be possible. The SPC has much of the Northland outlooked with a marginal risk which still is reasonable due to questions about the CAP. The front will be slow moving and will stretch from north central Lake Superior southwest into western Iowa at 12Z Friday. It will be cooler Friday with highs from the mid-sixties to lower seventies. Chances for showers/storms will continue over much of the Northland, highest over northwest Wisconsin and far northeast Minnesota with chances decreasing further west. An upper trough will settle over the region Friday and remain into Saturday. Chances for showers/storms will diminish Friday night into Saturday, lingering over northwest Wisconsin into adjacent east-central Minnesota. Global models show a stronger shortwave moving through the base of the trough with a closed upper low developing late Saturday night into Sunday. The GFS is faster moving the close upper low east with the ECMWF/Canadian slower. We prefer the slower ECMWF solution. The closed upper low is forecast to be far enough south of the Northland that dry conditions will occur for most areas. We do continue low chances for showers over parts of northwest Wisconsin. Drier conditions are expected for most Monday into Wednesday. Temperatures Saturday into Wednesday will be a few degrees either side of normal, cooler Saturday and Sunday. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 627 PM CDT Wed Sep 7 2022 VFR conditions across the Northland this evening. Overnight, LLWS will surge in from the southwest and impact most terminals until after sunrise. Winds will then translate down to the surface with southerly winds gusting into the upper 20s through the day. A cold front will be marching in from the northwest later in the period and may produce some showers and storms. Additionally, opaque skies will be widespread as smoke from the fires out west filter in. && .MARINE... Issued at 314 PM CDT Wed Sep 7 2022 Onshore winds less than 15 knots will continue through most of the night, becoming southerly late tonight into Thursday morning. The pressure gradient will strengthen Thursday and gusty southerly winds to 25 knots will occur, mainly from the Twin Ports region east along the South Shore. A few 30 knots gusts will be possible as well along the South Shore including Chequamegon Bay. A few thunderstorms will be possible along the North Shore late Thursday afternoon with chances increasing and spreading over the rest of western Lake Superior Thursday night. A few strong to severe storms will be possible. The gusty southerly winds will decrease Thursday night and veer to west to northwest behind the cold front. Speeds will be 15 knots or less later Thursday night into Friday. && .PRELIMINARY POINT TEMPS/POPS... DLH 59 85 58 65 / 0 20 60 60 INL 60 83 54 67 / 0 20 20 10 BRD 66 89 57 66 / 0 10 40 50 HYR 58 84 60 69 / 0 10 50 60 ASX 56 87 62 70 / 0 10 80 60 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Small Craft Advisory from 9 AM Thursday to midnight CDT Thursday night for LSZ121-146>148-150. Small Craft Advisory from 9 AM to 7 PM CDT Thursday for LSZ144- 145. && $$ DISCUSSION...Melde AVIATION...Britt MARINE...Melde
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Sioux Falls SD
1018 PM CDT Wed Sep 7 2022 .SHORT TERM...(This Evening through Thursday) Issued at 250 PM CDT Wed Sep 7 2022 KEY FORECAST POINTS: 1. Very warm Thursday with breezy winds 2. Fire weather concerns Thursday west of I-29 3. Rain chances Friday into Saturday 4. Cooler late week into the weekend Tonight: Quiet conditions expected through the overnight although winds aloft begin to increase after dark. Elevation favored areas such as the Buffalo Ridge likely stand the best chance to see the best fetch of this higher momentum air work toward the surface, pushing gusts into the 30-40 mph range. Thursday: Main concern for Thursday will be the increased fire weather danger courtesy of gustier winds, very warm temperatures and dry conditions. Prefrontal winds in a mechanically mixed atmosphere ahead of the front will result in south to southwesterly winds gusting between 25-35 mph through the afternoon hours. Meanwhile, 850 mb temperatures AOA the 90th percentile of climatology will push temperatures into the 90s and likely just above 100 through a narrow corridor of prefrontal compression near and west of the James River. .LONG TERM...(Thursday Night through Wednesday) Issued at 250 PM CDT Wed Sep 7 2022 Thursday Night: Initial wind shift to a more northerly direction arrives into our far western zones by late afternoon, continuing its southeastward trek through the overnight hours. Will carry a very small POP along/north of the Hwy 14 corridor through the first half of the overnight where a bit better support from the right entrance of the upper level jet may exist. Some additional light precip chances approach closer to the daybreak hours. We`ll also likely see an additional bump in wind gusts as stronger CAA arrives through the evening/overnight hours. HRRR smoke model suggest perhaps a bit of the upper level wildfire smoke may get drawn to the surface post-frontal but at this time, not expecting any impacts. Friday and Saturday: Post-frontal low/mid level frontogenesis should spin up a corridor of showers and embedded thunderstorms although progged soundings aren`t overly impressive for rainfall efficiency. The GFS/GEFS continue to sit on the low end of distribution in terms of QPF with only moderate odds (<50%) of greater than a tenth of an inch of rainfall while the deterministic ECMWF/NAM sit on the higher side with EPS odds of a tenth of an inch generally greater than 60%. GFS likely suffering from mixing biased issues but overall still looking at any rainfall amounts through the Friday/Saturday timeframe less than 0.5 inch in most locations. The potential caveat could be NW IA where amounts may sit on the higher side although ensemble probabilities suggest that WPC QPF may be on the higher side of the distribution. Run to run model consistency has been poor and thus will maintain the NBM/WPC approach to POPs/QPF at this time. Any rainfall by Saturday will likely focus through NE Nebraska, far SE South Dakota into NW Iowa. Amplified shortwave troughing overhead will allow for much cooler temperatures for late week with highs in the 60s and 70s. Sunday: Region sits through the backside of troughing by second half of the weekend with increasing sunshine, although temperatures remain seasonably cool in the upper 60s to mid 70s. Monday through Wednesday: Increasing influence from building ridging expected for the first half of the week although guidance spread on how quick temperatures respond still leaves some be to desire. GFS most aggressive with a wave later Tuesday with would result in a breezier period and perhaps some precip chances late in the period with ECMWF much more mute. && .AVIATION...(For the 06Z TAFS through 06Z Thursday Night) Issued at 1020 PM CDT Wed Sep 7 2022 VFR conditions prevail through Thursday as western wildfire smoke streams through aloft. Expect southerly winds to occasionally gust overnight with the southwesterly low level jet inducing low level wind shear through sunrise. Southerly winds strengthen ahead of an approaching front on Thursday with gusts of 20-30 kts expected. Winds will shift westerly and eventually northwesterly and gusty behind the front moving into central and eastern SD Thursday afternoon. && .FIRE WEATHER... Issued at 250 PM CDT Wed Sep 7 2022 Thursday will start the day with breezy south to southwest winds sustained 15 to 25 mph with some gusts 25 to 30 mph. As a cold front approaches from the northwest, winds will take on a more northerly direction. Meanwhile, adequate mixing and prefrontal compression will push temperatures into the 90s, even just above 100 for locations west of the James River. This will help drive relative humidity values toward or into critical values, especially west of I-29. The setback to perhaps more certain critical fire weather conditions will be a likely lull in wind speeds through this wind shift that may result in an ill-timed overlap of the stronger winds and lowest RH values. Current Fire Weather Watch covers the area of lowest RH (likely into critical values) while areas just east of the current watch may represent an area of higher winds but RH values just shy of critical values. One further fly in the ointment is any influence of upper level wildfire smoke on eventual mixing. Confidence just simply isn`t there to either expand the watch further east nor resolve the current watch area of a Red Flag Warning. Either way, areas west of I-29 and especially south of I-90 should see fire danger push into the Very High category, perhaps reaching warning criteria. Will allow future shifts to evaluate any headlines changes. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...Fire Weather Watch from Thursday morning through Thursday evening for SDZ050-052-053-057>059-063-064. MN...None. IA...None. NE...None. && $$ SHORT TERM...Kalin LONG TERM...Kalin AVIATION...BP FIRE WEATHER...Kalin
Area Forecast Discussion
National Weather Service Goodland KS
754 PM MDT Wed Sep 7 2022 .UPDATE... Issued at 752 PM MDT Wed Sep 7 2022 Forecast overall remains on track. Sky coverage was increased a bit for Thursday to account for the haziness from smoke aloft from the western CONUS fires as the HRRR Vertically Integrated Smoke continues to indicate that it will still be present. && .SHORT TERM...(This evening through Saturday) Issued at 109 PM MDT Wed Sep 7 2022 Hot and dry conditions continue through Thursday before cold front arrives on Friday and begins a dramatic cool down and chance for precipitation over the weekend. Temperatures will peak tomorrow in the upper 90s to lower 100s under the upper ridge centered over the western CONUS. Despite lack of much wind aloft for mixing, surface pressure gradient increases enough ahead of the front to the north to allow wind speeds to gust in the 20-30 kt range across much of the forecast area. The downsloping winds will also aid in drying, with dew points expected to tank into 30s and relative humidity to less than 15 percent. As a result, have issued a Red Flag Warning for all but the eastern areas for tomorrow. For Thursday night, cold front will begin to enter the far northwest areas (Yuma County) after 06z and already be about half way through the area by 12z. A few hours of breezy northwest winds will accompany the front. A few very light rain showers will also be possible. Low temperatures will be in the upper 50s to lower 60s. The cold front continues to move through the area Friday morning and will clear the final few counties in the southeast forecast area Friday afternoon. A few showers may linger into Friday morning along and behind the front. Thunderstorms will develop along the front Friday afternoon, but at this time appears that will occur just outside the area, but it will be close for Gove and Graham counties in Kansas. Otherwise, breezy north to northeast winds continue through the day behind the front with a rather large temperature gradient. Highs will range from the lower 70s in northeast Colorado to around 90 in Graham and Gove counties with later frontal passage. Post frontal showers and perhaps an isolated thunderstorms will develop Friday night. Low temperatures will range from the middle 40s to the middle 50s, coolest in Colorado. Saturday will be cloudy and much cooler with scattered light rain showers and isolated thunderstorms as the upper trough will be slow to move out and post frontal upslope continues. Precipitation amounts will generally range from a tenth to a quarter of an inch. High temperatures will generally be in the 60s. Showers will gradually come to an end Saturday night with lows in the 40s. .LONG TERM...(Sunday through Wednesday) Issued at 103 PM MDT Wed Sep 7 2022 Sunday is still looking to be cool with clearing skies followed by a warming trend through the first half of next week. In the upper-level, a trough will be sweeping through the area Sunday. As this trough moves through the region and exits to the southeast, it will remove most of the lingering moisture and clouds throughout the day Sunday. How fast the clouds move out will have an impact on the maximum temperatures, but we expect Sunday`s temperatures to top out in the low to mid 70s. Another dry spell is expected to set in and no precipitation is forecast in the long-term period. As the trough leaves, a ridge will begin building in behind it and keep the Tri-State skies mostly clear for the rest of the forecast period. At the surface early Monday morning, winds are expected to shift and begin coming from the south. These winds and clear skies will persist for the first half of next week and begin a warming trend throughout the region that could allow maximum temperatures on Wednesday to reach the low 90s. Minimum temperatures will follow a similar trend with Sunday night dropping into the mid and upper 40s while Tuesday night will remain in the 50s. Around Wednesday next week, guidance differs as the upper-level ridge axis begins to move over the region. The ECMWF is showing a more zonal flow with a less amplified ridge moving over the Rockies while the GFS is showing a well amplified ridge promptly followed by a mid-level shortwave. This will be a feature worth watching over the next few days to see how it develops. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 451 PM MDT Wed Sep 7 2022 VFR conditions are expected throughout the entire period at each site. An area of smoke aloft is moving south across the northern plains, no surface restrictions are expected. Winds will briefly become light for a few hours before the low level wind field increases again allowing winds to become sustained around 12-15 knots overnight at KGLD. LLWS is expected to occur overnight at KMCK as surface winds remain below 10 knots. LLWS will end around sunrise as winds become breezy mid morning as diurnal mixing begins. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Red Flag Warning from 10 AM to 7 PM MDT Thursday for KSZ001>003- 013-014-027-028-041-042. CO...Red Flag Warning from 10 AM to 7 PM MDT Thursday for COZ252>254. NE...Red Flag Warning from 10 AM to 7 PM MDT Thursday for NEZ079>081. && $$ UPDATE...Trigg SHORT TERM...024 LONG TERM...CA AVIATION...Trigg
Area Forecast Discussion
National Weather Service Grand Rapids MI
729 PM EDT Wed Sep 7 2022 LATEST UPDATE... Aviation .DISCUSSION...(This evening through next Wednesday) Issued at 203 PM EDT Wed Sep 7 2022 - Locally dense fog possible tonight Surface dewpoints will be elevated along and west of US 131 due to wind coming off of Lake MI. With mainly clear skies and light winds predicted for tonight...this should lead to good radiational cooling. Forecast low temperatures are shown to be at least several degrees below the current surface dewpoints. This all points to a risk for fog redevelopment. The 16z HRRR shows areas of dense fog closer to the lakeshore later tonight which could lead to some impact. We will feature a risk for fog tonight and mention the impacts in the Hazardous Weather Outlook. Any fog should not last long after sunrise...similar to today. - Increasing potential for showers and thunderstorms early next week Overall there is still a lot of model spread on how this scenario could evolve...but the general theme is for increasing potential for rain. A mid to upper level low forms over the Central Plains on Sunday. This system then drifts slowly east into the Southern Great Lakes region through Monday. At the same time...a low is shown to be lifting northward out of the Gulf and that system gets absorbed in the mid to upper level low. The added moisture from this southern system will increase the excessive rain risk. We will feature the highest POPs in the Sunday to Monday window. For Tuesday into Wednesday...the region will still be under the influence of this system but there are some indications the the deepest moisture will shift east of the CWA during this period. With a cold pool aloft...we may transition to more of a diurnally driven shower/storm pattern Tuesday into Wednesday. For the entire event...rainfall could be efficient with this system as the forecast soundings are showing low LCL`s and thin deep CAPE. In addition...PWAT values in most models suggest we will approach 2 inches especially over southern parts of the CWA Sunday into Monday. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 704 PM EDT Wed Sep 7 2022 I expect nearly clear skies tonight, and for that matter Thursday too. With the surface high overhead tonight, and then moving off to the east on Thursday, surface winds will be light and variable. MKG and maybe GRR will see a lake breeze wind shift mid to late afternoon Thursday. Shallow dense fog is expected from around 2 am till around 7 am Thursday morning. Seems the GRR and MKG taf sites would see the most impact from the fog early Thursday morning. All TAF sites will become clear by 13-14z. m && .MARINE... Issued at 203 PM EDT Wed Sep 7 2022 South winds will be on the increase Thursday night into Friday as a warm air advection pattern sets up. Gust for the most part look like they will stay under 20 knots so no headlines will be issued at this time. The highest waves will over the northern zones given the longer fetch...however they are projected to remain mostly under 4 feet. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...None. && $$ DISCUSSION...MJS AVIATION...WDM MARINE...MJS
Area Forecast Discussion
National Weather Service Northern Indiana
810 PM EDT Wed Sep 7 2022 .SYNOPSIS... Issued at 808 PM EDT Wed Sep 7 2022 High pressure will provide dry weather into at least Saturday morning. Temperatures start out close to normal on Thursday with highs in the upper 70s to lower 80s. The heat and humidity then gradually build into the weekend and provide a chance of showers and a few thunderstorms Saturday afternoon into early next week. The best chance of rain is Sunday afternoon into Sunday night. && .SHORT TERM...(This Evening through Thursday) Issued at 116 PM EDT Wed Sep 7 2022 Pleasant afternoon with plenty of fair weather cumulus under the mid-level inversion associated with high pressure ridging. Generally light winds and subsidence will allow high temperatures to rise to rise into the upper 70s. Northerly flow will enhance the lake breeze this afternoon and evening which will lead to slightly cooler temperatures near the lake where highs are expected to be in the low to mid 70s. Winds will die down overnight and skies will clear, leading to patchy to locally dense once again. Hi-res models are indicating that fog will be most likely across northwest Indiana. This is possibly due to slightly higher low level moisture being downwind from Lake Michigan. High pressure will shift east on Thursday, and the increased warming will cause afternoon high temperatures to rise to around 80. && .LONG TERM...(Thursday Night through Wednesday) Issued at 116 PM EDT Wed Sep 7 2022 It will continue to warm going into the weekend as the ridge moves over the region and then into the mid-Atlantic. The resulting subsidence will keep the area dry and push daytime highs into the low 80s for Friday and Saturday. A Gulf low will bring moisture and energy up through Mississippi Valley on Saturday, and showers and thunderstorms are expected to lift into the region Saturday evening. Another low will develop over the central plains on Sunday, which will then slowly meander across Illinois and Indiana for the through at least Tuesday, and keep convective activity going. A few showers may linger on Wednesday even as the low finally moves east of the region. Temperatures will fall into the low to mid 70s during this period. && .AVIATION...(For the 00Z TAFS through 00Z Thursday Evening) Issued at 808 PM EDT Wed Sep 7 2022 Subsident surface ridge over the Upper Great Lakes into the Middle Mississippi Valley will shift eastward into the Lower Great Lakes over the next 24 hours. Extremely dry air mass to provide VFR conditions. The only exception will be the potential for what should be only MVFR visibility restrictions around daybreak at peak of radiational cooling. Sharp surface based inversion and lows 2-4F below KSBN/KFWA of 57/56, respectively, along with supporting 21 UTC HRRR with expanding MVFR, plus/minus about an hour either side of sunrise. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...Murphy SHORT TERM...Cobb LONG TERM...Cobb AVIATION...Murphy Visit us at www.weather.gov/iwx Follow us on Facebook...Twitter...and YouTube at: www.facebook.com/NWSNorthernIndiana www.twitter.com/nwsiwx www.youtube.com/NWSNorthernIndiana
Area Forecast Discussion
National Weather Service North Platte NE
718 PM CDT Wed Sep 7 2022 .SHORT TERM...(This evening through Thursday night) Issued at 355 PM CDT Wed Sep 7 2022 The main concern in the short term will be near record to record highs on Thursday, fire weather concerns Thursday and precipitation chances for Thursday along with smoke potential. For high temperatures, models continue to trend warmer and went with the 90th percentile as this setup looks favorable for some very hot temperatures by September standards. Some of the warmest temperatures will be out ahead of the front with many locations reaching the low 100s. Currently some of the climate sites, including North Platte are forecast to break records, see climate section for record temperature information. There will be some smoke potential tonight and Thursday. The HRRR model is showing some sfc smoke however it remains pretty low through the day which leads to low confidence of smoke impacting visibility at the SFC. That being said, there is a somewhat significant increase in vertically integrated smoke across much of the forecast through this afternoon into Thursday, thus confidence has increased in the probability of having some elevated smoke in the area, or haze, have added some cloud cover to account for this. Confidence is low that this will have any impact on high temperatures for tomorrow. As for precipitation with the frontal passage, there will be a lot of dry air out ahead of the front with precipitation looking less likely at least through the afternoon. Heading into the evening hours there may be the potential for some thunderstorm development along and behind the front. However, again with low level moisture lacking there is more confidence that any thunderstorm that does develop with be LP in nature and there is the potential for some dry lightning, which could lead to fire starts. .LONG TERM...(Friday through Wednesday) Issued at 355 PM CDT Wed Sep 7 2022 With the ridge breaking down, it will finally give some reprieve to the hot summer temperatures with highs finally cooler with highs in the 60s to low 70s for Friday. This is actually below normal temps for this time of year, around 5 to 15 degrees below normal. As a trof pushes through on Saturday, another bout of colder air will pull in from the north reinforcing the cool temperatures with highs struggling to reach just above 60 degrees. Precipitation chances will increase Friday night into Saturday, as moisture returns look favorable for some widespread precipitation across the area. Most locations are expected to see some sort of moisture, but generally on the lighter side, less than a quarter of an inch. There is however some confidence in the models that a corridor of precip near a half inch total qpf may be possible across the eastern and central Nebraska into portions of the southwest Nebraska. If this holds in later model runs there is a good chance some locations in our southern and eastern forecast area may see some beneficial rains. Unfortunately the cooler temperatures are short lived as an upper level ridge begins to build back into the southwest CONUS at the start of the work week bringing us a return to the northwest flow and warmer temperatures next week. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 648 PM CDT Wed Sep 7 2022 VFR conditions are expected to prevail tonight through Thursday across western and north central Nebraska. There will be some hazy skies due to smoke but this should remain aloft and not impact VSBY at the surface. Low-level wind shear will be of concern tonight into early Thursday morning and this is outlined in area TAFs. Gusty south to southwest winds are expected Thursday. && .FIRE WEATHER... Issued at 355 PM CDT Wed Sep 7 2022 A Red Flag warning has been issued for the entire forecast area as conditions will be favorable as the combination of gusty winds, low humidity and even dry lightning concerns will lead to critical fire weather concerns. Overnight recovery tonight will be lacking, especially across western Nebraska and the northern Sandhills where RH will range from 30 to 50 percent overnight. As for tomorrow there will also be very warm temperatures in the afternoon with highs reaching the low 100s across most locations of western, southwest and north central Nebraska, including the Sandhills. There will also be the concern with dry conditions and thunderstorm potential that any thunderstorms that develop will have a lack of moisture, thus leading to dry lightning concerns, which could be fire starters. Winds will be gusty with wind gust of 25 to 30 mph expected mainly out of the southwest. There will be a wind shift to also take in consideration as the front moves across the Sandhills and north central Nebraska during the day, winds will shift to the north. && .CLIMATE... Issued at 356 PM CDT Wed Sep 7 2022 Temperatures for Thursday will range from 20 to 25 degrees above normal. For North Platte the record high for September 8th is 101 degrees set in 2013, with a forecast high of 104. The record highs for Valentine is 101 degrees set in 1931 with a forecast high of 104. Imperial`s record high is 102 degrees set in 1977, with a forecast of 104 degrees. && .LBF WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 11 AM to 8 PM CDT Thursday for NEZ204-206- 208>210-219. && $$ SHORT TERM...Gomez LONG TERM...Gomez AVIATION...Taylor FIRE WEATHER...Gomez CLIMATE...Gomez
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
829 PM CDT Wed Sep 7 2022 .UPDATE... Issued at 829 PM CDT Wed Sep 7 2022 Expecting redevelopment of patchy fog by early Thursday morning, with some potential for more widespread fog west and southeast of Chicago. Have made some minor adjustments to increase fog wording in these spots after midnight, otherwise going forecast is in good shape this evening. Quiet weather conditions remain in placed across the forecast area this evening, beneath eastern periphery of the western CONUS/Plains upper ridge. At the surface, 1019 mb high pressure was centered over the IL/WI/IA border region per latest analysis and was providing generally light/variable or calm winds across the area with the exception of light east-northeast winds near Lake Michigan associated with the decaying diurnal lake breeze circulation. Other than a little patchy, thin cirrus dropping south across northern and central WI (and a bit of haziness aloft associated with elevated smoke from western wildfires per late-day GOES-16 visible imagery and HRRR smoke graphics), skies will remain clear overnight. Only real weather concern overnight is the potential for patchy fog development again after midnight. Afternoon surface dew points in the upper 50s/low 60s in many spots combined with calm winds will likely allow for patchy shallow radiational fog away from the warmer core of the Chicago metro area during the pre-dawn hours of early Thursday. High-res guidance again indicates parts of north/northwest IL from the Fox River Valley westward, and areas from Kankakee eastward into northwest IN for perhaps the greatest fog potential. RAP forecast soundings depict the deepest moist hydrolapse profiles south and southeast of the Chicago area, and visibility guidance generally indicates lowest visibilities in the vicinity of the Kankakee River Valley into Thursday morning. Have increased fog coverage wording in forecast for now, and would not be surprised to again need a dense fog advisory for portions of the area by morning. Otherwise, expecting overnight lows from the mid-50s in coolest inland locations to the lower 60s in Chicago proper. Going forecast has this well in hand, and other than enhancing fog wording in aforementioned areas, no changes appear necessary. Ratzer && .SHORT TERM... Issued at 148 PM CDT Wed Sep 7 2022 Through Thursday night... Only forecast concern is fog potential tonight/Thursday morning. High pressure will settle across the area tonight allowing for clear skies and mainly calm winds. This should allow for at least patchy fog to develop away from Chicago. Much of the guidance shows fog by Thursday morning, but there remains uncertainty for how widespread or dense the fog may become. Appears the most favored area for potential dense fog will be the northwest cwa and trends will need to be monitored later this evening into early Thursday morning. Any fog that forms will dissipate quickly after sunrise Thursday morning. Low temps tonight likely to be in the 50s for most of the area, warmer in Chicago. Winds will remain light on Thursday, turning southerly as the high shifts east. A lake breeze is likely keeping the lakeshore area a few degrees cooler, with highs in the lower/mid 80s inland. Still some uncertainty for how far inland the lake breeze will move. While surface winds will remain light southerly Thursday night, likely under 10 mph, winds just above the surface are forecast to steadily increase through the night and this should limit if not prevent fog development Thursday night into Friday morning. cms && .LONG TERM... Issued at 303 PM CDT Wed Sep 7 2022 Friday through Wednesday... Another tranquil, mostly clear, and cool night is on tap at the start of the long term period Friday. Surface high pressure will begin to develop more meaningfully eastward on Friday, and this will allow southerly gradient flow to return. A lake breeze will turn winds out of the southeast/east-southeast which will probably hold lakeside areas across Lake County Illinois in the upper 70s/lower 80s, with mid 80s more prevalent with inland extent. Somewhat more unsettled conditions look to return during the weekend, but latest indications continue to point to much of Saturday likely staying dry as we`ll remain within a col/saddle point within the upper level flow. Any isolated shower/storm chances look to hold off until later in the afternoon, and it`s possible the entire afternoon remains precip-free area-wide. Guidance is still in decent agreement regarding the character of the large scale flow towards Sunday and Monday, with a large cut- off circulation developing somewhere across the Upper Midwest. However, the specifics regarding timing and location of any phasing associated with a southward-advancing PV anomaly still remain up in the air. Periods of scattered showers and perhaps a storm or two seem to characterize the most probable outcome of things on Sunday, and possibly into Monday, with just too much uncertainty to advertise anything more than high-end chance PoPs at this point. The cessation of precipitation chances and temporarily gloomier weather remains unclear at this time with slower/deeper solutions suggestive of chances lingering into Tuesday. Carlaw/BMD && .AVIATION... For the 00Z TAFs... The primary aviation weather concerns through the 00Z TAF period are as follows: * The potential for some Thursday morning fog at DPA, GYY, and RFD NE flow under 10 kts will continue into the latter part of the evening before winds subside to below 5 kts and become variable in direction for the night. By mid-morning on Thursday, winds will establish a southerly direction eventually building to just under 10 kts by the afternoon. Predominantly southerly flow will then take us through the end of the TAF period while remaining under 10 kts. It`s likely that winds will teeter on either side of southerly from time to time, especially Thursday morning and evening. Additionally, fog is expected to develop across parts of the suburbs early Thursday morning which could potentially impact DPA, GYY, and RFD. MVFR vsbys appear probable should fog develop over the airfields with a drop below IFR thresholds also possible. Conditions should improve to VFR by, or shortly after, 13Z. At ORD and MDW, VFR conditions can be expected through the entirety of the period. Doom && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...None. && $$ Visit us at weather.gov/chicago Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSChicago www.twitter.com/NWSChicago www.youtube.com/NWSChicago
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