Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/26/22


Area Forecast Discussion
National Weather Service Bismarck ND
1048 PM CDT Mon Jul 25 2022 .UPDATE... Issued at 1047 PM CDT Mon Jul 25 2022 A line of showers and thunderstorms continue to move along a cold front across the state this evening. Initial convection ran into increased 0 to 3 KM shear and a small pocket of high DCAPE over 1000 J/KG. This brought some wind gusts over 60 MPH this evening. Although the 0 to 3 KM shear and MUCAPE will remain elevated into the early overnight hours, DCAPE is diminishing. Perhaps a strong gust of wind up to 60 MPH is still possible tonight, although the window is closing fast. And with low overall shear and standard mid level lapse rates, the threat for hail is even lower. Made some minor tweaks to pops based on current trends. Look for cooler temperatures and an increased northwest breeze on Tuesday. Some showers may linger through tonight into Tuesday morning, then redevelop Tuesday afternoon. UPDATE Issued at 659 PM CDT Mon Jul 25 2022 Surface front and upper level wave starting to push into northwest North Dakota. As a result a few showers and thunderstorms are starting to develop early this evening. Ahead of this front mix layer and most unstable of 1000-2000 J/KG is currently being observed. This does get more and more capped as the evening progresses. The bigger inhibitor to severe weather through the evening is the lack of shear. Effective shear of 25 to 35 knots through the evening is enough to perhaps bring an isolated stronger storm, but overall widespread severe weather is still not expected. Some of the stronger storms could produce some hail up to quarter size. The main concern would be wind gusts up to 60 mph as DCAPE ahead of the front is near 1000 J/KG and the bulk of the shear is in the 0 to 3 km area. Made some minor adjustments to pops based on current trends. && .SHORT TERM...(This afternoon through Tuesday) Issued at 305 PM CDT Mon Jul 25 2022 Most of western and central North Dakota is under the influence of low amplitude ridging. However, a compact shortwave continues to move east southeast through South Dakota underneath the ridge in a split flow regime. The main impact from the southern wave will be continued cloud cover over the southern third of the state, keeping temperatures a bit cooler than initially expected. A few showers and an isolated rumble of thunder will continue to be possible this afternoon along and near the South Dakota border as the wave moves east. Later this afternoon and tonight, the next (stronger) wave will ride down a highly amplified western ridge, it`s axis extending almost into the Gulf of Alaska. At the surface, this wave should interact with a cold front that will move into northwest North Dakota this evening. Showers and thunderstorms will become likely along this front as it moves southeast across the state in the evening and overnight hours. When storms move into the northwest, the initial environment will not be very impressive with weak instability and marginal shear. However, as the front continues to move into the central and south central/southeast, storms will encounter richer moisture, leading to stronger elevated instability. The last few runs of the HRRR and RAP suggest MUCAPE could increase into the 1000 to 2000 J/kg range across portions of the central/south central around and after midnight as storms approach. Deep layer shear will remain fairly marginal with 0-6km values ranging from 25 to 35 knots. Therefore, a few strong storms are possible and a marginal severe storm or two is not out of the question if storms can tap into the better elevated instability. The main impact would likely be small hail, but a report or two up to the size of a quarter seems reasonable. The wind threat is a little bit more unclear given the nocturnal frontal passage, but 0-3km shear will be fairly strong along the front, in the 25 to 35 knot range. If stronger velocities can mix down through the boundary layer some stronger gusts are not out of the question. The main push of precipitation should move out of the James River Valley by Tuesday morning at around 09-12z or so, but a few lingering showers and maybe a rumble of thunder will be possible behind the front through the morning. An upper low will then close off over northern Manitoba, placing our area in cyclonic northwest flow aloft. Diurnal heating should lead to isolated showers (maybe some thunder south or east) over much of western and central North Dakota. Decided to go ahead and blanket pretty much the whole area with isolated precipitation chances as CAMs are advertising hit and miss popcorn convection across all of western and central North Dakota by the afternoon. Regarding lows tonight: areas south, central, and east will probably see lows around normal (upper 50s to lower 60s) but locations in the northwest will see lows dip into the lower 50s behind the cold front. The passage of this front will also lead to cooler and below normal high temperatures in the 70s on Tuesday. .LONG TERM...(Tuesday night through Monday) Issued at 305 PM CDT Mon Jul 25 2022 A few showers may linger across portions of the central and east Tuesday evening, but should diminish rather quickly as we lose diurnal heating. Lows will be in the low to mid 50s. On Wednesday, the closed low over northern Manitoba will drift slowly southeast into western Ontario, keeping us in northwest flow aloft. Given lingering cyclonic flow aloft, a few afternoon showers may pop up again across the northeast, into portions of the Turtle Mountains and Devil`s Lake Basin. The pressure gradient will also tighten a bit as the closed low moves south into Ontario, so Wednesday afternoon will become breezy with winds out of the north northwest. Temperatures will remain below normal Wednesday afternoon with highs in the 70s, and then a seasonably cool night is on tap Wednesday night. The NBM suggests that we will dip into the mid 40s to lower 50s, and that may even be on the high side depending on how cloud cover evolves. Given uncertainty regarding cloud cover, will keep with NBM lows for now, but they may have to be nudged even lower if/when confidence builds for areas under a clear sky all night. Through the rest of the period, ridging to our west will slowly move in, with the axis moving overhead sometime on Friday, transitioning to near zonal flow through the weekend. This will mean another cool day Thursday, followed by a warmup Friday and into the weekend (a return to the 90s for most across the central and west). Most guidance has a trough skirting us to the north on Saturday, and the NBM has started to advertise slight precipitation/thunderstorm chances by Saturday evening which seems reasonable at this range. Warm temperatures then continue into the next work week. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 659 PM CDT Mon Jul 25 2022 Through this evening, showers and storms will become likely northwest and spread east southeast through the overnight hours. VFR conditions are generally expected through the evening hours, with some MVFR conditions under any thunderstorms. Most sites have VCTS/VCSH with some TEMPO groups added to sites with higher confidence of shower and thunderstorm activity. MVFR conditions are then possible tonight as low clouds linger behind a passing cold front. Tuesday sees some low clouds lift later in the morning back to VFR heights. Winds will become northwest on Tuesday, and perhaps breezy at times in the afternoon. A few isolated showers are also possible through Tuesday, although confidence was not high enough to include at this time. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Anglin SHORT TERM...ZH LONG TERM...ZH AVIATION...Anglin
Area Forecast Discussion
National Weather Service Cheyenne WY
526 PM MDT Mon Jul 25 2022 .SHORT TERM...(This evening through Tuesday) Issued at 241 PM MDT Mon Jul 25 2022 Dry and breezy weather will continue through the evening hours across much of southeast Wyoming. Westerly surface flow is expected to relax as the evening progresses as surface mixing ceases and overnight inversions set in. CAM guidance remains mainly dry however an isolated shower or thunderstorm is still possible just west of the dryline boundary currently located near Pine Bluff. Any shower or storm will be brief and this low chance will drop to near 0% after around 9pm. Overnight expect seasonal temperatures with mainly clear skies. Light westerly flow aloft will continue on Tuesday. Surface moisture east of I-25 will remain in place as a light upslope flow component lingers in the lowest 2km of the profile. CAM guidance has been quite dispersive with potential forecast outcomes on Tuesday. The notoriously dry and over-mixed HRRR continues to show little in the way of any shower or thunderstorm activity, similar to the FV3. The NAM Nest and NSSL-WRF keep deeper and greater surface moisture in place and thus fire a few thunderstorms generally along and east of the Laramie Range. Given around 30-35 knots of 500mb flow in place resulting in 0-6km bulk shear near 40kts, any thunderstorm that can form on Tuesday afternoon and evening could be strong, with hail and gusty winds the primary threats. This threat remains quite conditional however, with capping, poor mid-level lapse rates, and the aforementioned questionable surface moisture the primary limiting factors. Still, the convective forecast on Tuesday is worth keeping an eye on given the potential upside if all favorable elements do come together. Temperatures will continue to run near average through the short term. .LONG TERM...(Tuesday night through Monday) Issued at 241 PM MDT Mon Jul 25 2022 Key Impact Messages: 1) Persistent deterministic and ensemble model guidance continues to highlight above normal atmospheric moisture and resultant above normal rain chances mid to late week. This will especially be in place Thursday and Friday for central portions of southeast WY and central to south NE Panhandle. 2) Temperatures will near seasonable normals to slightly below normal mid- to late-week and then warm into the weekend to slightly above normal. Weather Discussion: Wednesday will begin the moisture infiltration period for East WY and the NE Panhandle while the remnant low-level dry air tries to hold on. This combination of greater mositure in NW H7-H3 flow and higher instability should yield isolated to scattered thunderstorms that could be strong to briefly severe along and east of the Laramie Range. With inverted "V" soundings, wind gusts of 40- 60 mph, isolated areas of quarter hail, and frequent lightning will be possible with any more robust updraft. For Thursday, PWATs continue to increase as monsoonal moisure rotates in from the north and west while being compressed by slightly drier airmass just NE in the Dakotas with east upslope flow. +2 to +3 standard deviations above normal PWATs near 1.1" to 1.4" look to be in place for far SE WY and central to southern NE Panhandle by Thursday afternoon. Tall, skinny CAPE profiles and 30kt 0-6km shear does not overly support strong to severe weather but will support moderate to heavy rain pockets with average storm motion at 15-20 mph. Potentially even slower storm motions could be possible over the higher terrain per model soundings. This could set the stage for localized flash flooding, especially if these storms form near or over the Mullen burn scar. NWS WPC is already highlighting a Slight Risk of Excessive Rainfall on Day 4 across far SE WY and it`s likely this could expand farther north in the coming days if this anomalous moisture signal remains on track. High PWATs remain in place Friday for the same area with slightly reduced east upslope to more south flow, that in some places, still is upslope, and will need to monitor again for localized heavy rain leading to flash flooding for far SE WY and southern NE Panhandle with slow storm motions. PWATs remain +1 to +2 deviations above normal Saturday as a stronger shortwave impulse shifts southeast into MT/ND but its influence remains farther north. This could be another day for localized moderate rain while available moisture becomes slightly lower with few focus mechanisms. However, Thursday-Saturday - could be impactful days near or on the Mullen Burn Scar. Sunday appears drier with the H5 ridge center shifting farther east over SW WY and shifting drier air into SE WY and west NE. Stay tuned through mid- week for more updates on this flash flooding risk. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 524 PM MDT Mon Jul 25 2022 Wyoming TAFS...VFR. Wind gusts to 30 knots until 03Z, then gusts to 23 knots at Laramie and Cheyenne after 15Z Tuesday. Nebraska TAFS...VFR. Wind gusts to 25 knots at Alliance and Sidney until 06Z, then gusts to 25 knots at all terminals after 14Z Tuesday. && .FIRE WEATHER... Issued at 241 PM MDT Mon Jul 25 2022 Borderline critical fire weather conditions are possible this Monday afternoon over southeast Wyoming. Gusty winds in excess of 20 mph have been reported at RWL and LAR and will continue through the early evening with RH in the 15-20% range. On Tuesday, expect lower wind speeds in southeast Wyoming however RH values will still be relatively low in Carbon County. Increasing monsoonal moisture will return by mid and late week with wetting rains looking more likely for Thursday. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...MAC LONG TERM...JSA AVIATION...RUBIN FIRE WEATHER...MAC
Area Forecast Discussion UPDATED
National Weather Service Hanford CA
410 PM PDT Mon Jul 25 2022 ...UPDATED AIR QUALITY ISSUES SECTION... .SYNOPSIS... Triple digit temperatures in the valley and Sierra foothills with daily chances of showers and thunderstorms over the Sierra will continue through the seven day forecast period. Smoke from the Oak Fire will impact air quality throughout the district. && .DISCUSSION... The heat continues. Today will see the 15th consecutive day of triple digit heat for the Fresno and Bakersfield areas. Yet, we’ll fall well short of the 28 days with 100 degrees over higher set back in 2018. The blocking high pattern over the West Coast shows no sign of breaking down as surface pressure gradients from KSFO to KLAS at around 2mb as surface winds remain very light. However, mid-level wind flow aloft under the current weather pattern will support a northwest surge moisture into the region. Therefore, current trend is to stay in the 100 degree range for the remainder of the month with convection from monsoonal moisture being the variable over the region for the next several days. Rex blocking pattern over the Eastern Pacific will help maintain the triple digit temperatures observed over the Central California Interior over the next seven days (ending at the start of August). The only uncertainty in the persistent triple digit forecast will be the intrusion of thunderstorms over the Valley from the Southwest Monsoon. While ensemble data does not pick up on a piece of energy moving through the southeasterly flow Tuesday morning, the deterministic HRRR and NestNAM have been consistent for several runs on attempting the introduce overnight convection across Merced/Madera/Mariposa Counties just before sunrise on Tuesday during the weak piece of energy’s passage. Therefore, will maintain a mention a slight chance of thunderstorms overnight over the valley and skirt the foothills near the Oak Fire. Will monitor the situation on possible hazards overnight. While convection will continue into the day on Tuesday, ensemble confine its activity over the Crest of the Sierra as orographic lift remains as the sole generator of convection during the day. Wednesday will see no change in the flow aloft as monsoonal moisture spreads further north with better chances of Sierra Nevada crest Convection. Without any impulses, will not expected convection to reach other parts of the district. Longer term ensemble does not show any big changes in the flow aloft through the end of the week. The blocking ridge will remain the dominate feature as shown on Cluster Analysis through at least Saturday. Therefore, hot with conditions approaching heat advisory condition near the end of the week. Will see how ensemble analysis continues to handle the latter periods. By Sunday, Cluster Analysis shows the ridge in place, but not as strong a signal as the days before. The end of the period on day Seven (Monday) shows further break- down of the ridge as several ensemble members in the Cluster Analysis lean in favor of a deeper trough passage next week. While too early to say of significant cooling will occur, will trend temperatures slight cooler and see if the ensemble continue in the direction of a trough solution. && .AVIATION... MVFR or lower visibilities are likely in Mariposa and Madera Counties due to heavy smoke and haze from the Oak Fire. Otherwise, VFR conditions will prevail across the remainder of Central California for at least the next 24 hours. && .AIR QUALITY ISSUES... On Tuesday July 26 2022...Unhealthy for Sensitive Groups in Fresno... Kern... Madera... Merced and Tulare Counties... and Sequoia National Park and Forest. && .CERTAINTY... The level of certainty for days 1 and 2 is high. The level of certainty for days 3 through 7 is medium. Certainty levels include low...medium...and high. Please visit www.weather.gov/hnx/certainty.html for additional information an/or to provide feedback. && .HNX WATCHES/WARNINGS/ADVISORIES... None. && $$ Public/Aviation/Fire Wx...Molina IDSS/PIO/Social Media.....JDB weather.gov/hanford
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1045 PM EDT Mon Jul 25 2022 .UPDATE... Issued at 1045 PM EDT MON JUL 25 2022 Sustained convection continues in a couple spots through the state and will likely be around into the night. Have updated the forecast mainly to fine tune the PoPs per the radar trends and latest CAMs guidance. Did also add in the latest obs and trends for the T/Td grids. These updates have been sent to the NDFD and web servers. UPDATE Issued at 745 PM EDT MON JUL 25 2022 23Z sfc analysis shows a frontal boundary stalling out over eastern Kentucky. This is prompting showers and thunderstorms to develop and drift east. The heat is starting to wan now so expect the convective activity to begin settling down soon, as well. However, there remains enough instability around for a few more storms to develop and impact the area where they will be able to tap into a very moist air mass and potentially train - continuing excessive rain concerns into the night. Otherwise, temperatures are running in the mid to upper 70s most places while the dewpoints remain quite elevated in the mid 70s - amid light winds away from any storms. Have updated the forecast mainly to fine tune the PoPs and fog details through the rest of the evening and into the late night. Did also include the latest obs and trends for the T/Td grids. These updates have been sent to the NDFD and web servers along with a freshening of the zones and SAFs. && .SHORT TERM...(This evening through Tuesday night) Issued at 329 PM EDT MON JUL 25 2022 The afternoon surface analysis shows the main quasi-stationary boundary remains just to the north and west of eastern Kentucky. However, a more subtle moisture boundary is set up from west to the east along the Mountain Parkway based on satellite and radar observations, as showers and thunderstorms are noted to be developing along this moisture boundary. This is where MLCAPE values of 1500-2000 J/kg that is tall and skinny and PWAT values of around 2 inches resides leading to the potential for efficient rain makers across eastern Kentucky this afternoon and evening. So far the activity has had the storm motions to keep from this being an issue just yet, but if we get multiple rounds of convection we could see localized Flash Flooding through the afternoon and evening. After we lose the day time heating this evening, the showers and thunderstorm activity will decrease in coverage across eastern Kentucky. This will allow for fog and potentially stratus develop depending on if cloud coverage decreases more and dependent on locations that get rainfall. The CAMs and other models are in decent agreement with another embedded shortwave arriving Tuesday amid the zonal flow aloft. There remains a fair amount of uncertainty when precipitation arrives with the HRRR remaining most bullish on timing by late tonight toward dawn Tuesday. Given this did increase PoPs toward Dawn, but hold off on greater than 60 percent PoPs. This as HREF shows greater than 2 inch PWAT probabilities increasing most mainly after 12z becoming 80 to 90 percent chance by the afternoon. Tuesday the aforementioned front will push northward as a warm front. Then the previously mentioned shortwave will ride along the zonal flow aloft into the Ohio Valley. This will help to redevelop showers and thunderstorms mainly through the afternoon and evening. The ensemble tables remain in the 90th percentile or greater for PWATs Tuesday and this combined with any training storms from Monday helping to weaken flash flood guidance could lead to localized flash flooding once again. There is a marginal risk from SPC for a locally severe storm, but DCAPE values less than 900 J/kg and weak flow would think this would be a isolated set up at best. Did opt to go a bit cooler than Monday given a little more cloud cover is possible. Tuesday night this boundary remains nearby across the Ohio Valley. We will see a relative lower chance of PoPs in the early evening hours. Later yet another wave arrives leading to a resurgence of showers and thunderstorms through the night into early Wednesday morning. This combined with ample PWAT values remaining in place will continue to localized flash flood threat. This can be especially concerning given the potential some of this activity would be lower centroid storms and the HREF does show the potential for heavier swaths mainly north of the Hal Rogers Parkway/KY 80 closer to the boundary. .LONG TERM...(Wednesday through Monday) Issued at 420 PM EDT MON JUL 25 2022 The models are in fairly good agreement aloft through the long term portion of the forecast. They all depict Kentucky on the north side of a broad and flat ridge to start the period. This will help to channel the faster and more zonal flow through the state - carrying ample amounts of mid level energy. Towards the weekend, heights will start to fall further as a trough deepens over the Great Lakes sending more energy into the JKL CWA with a 5h trough axis passing through Friday evening. The ECMWF is a bit stronger and faster with this transition than the GFS suite likely affecting the sfc features with its front dropping more distinctly south of the state that night compared to the GFS`s version stalling more overhead. The heights then rebound a bit for the rest of the weekend but troughing will remain over the Ohio Valley maintaining a flow of energy into Kentucky through Monday. The overall model spread is small with just that minor bump of discrepancy a concern on Friday night so have generally gone with the blended NBM solution with little adjustments through the period. Sensible weather will be quite wet through the breadth of the extended portion of the forecast with that stalled front over the area throughout. This boundary will help to focus anomalously high PW air likely resulting in repeated clusters of showers and storms crossing the area. A thorough soaking can be expected with most places probably seeing 2 plus inches of rain through the weekend with a few spots likely pushing 4 to 5 inches by Monday. The cumulative effect of the rain will almost certainly necessitate an extended flood watch during this period with few flood warnings anticipated for places that see significant training. Climatologically, to have a stalled boundary in place for many days through this part of the nation during the summer is relatively rare and worth noting regardless of its potential for excessive rains owing to its coincidence with the high moisture air mass in place. Most of the storms through the period will be sub-severe, but some gusty winds - possibly capable for blowing trees down - can be expected from the strongest of them. The only bright spot will be an end to our temperatures in the 90s, though the high humidity will keep conditions sticky and uncomfortable - along with muggy nighttime temperatures. The NBM grids had the wet nature of the forecast well in hand and only needed a bit of tinkering Friday night for some lowing of the PoPs in the north. With that, also tweaked the temperatures overnight for some enhanced terrain distinctions north into Saturday morning. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) ISSUED AT 815 PM EDT MON JUL 25 2022 Most sites have returned to VFR conditions as the convection has generally shifted off to the east of the TAF airports. Overall, expecting a mix of VFR to MVFR through the evening depending on if sites experience direct shots from any lingering showers and thunderstorms. A general lowering of the CIGs and some light visibility restrictions follow later tonight into Tuesday morning. Winds will remain light at 5 to 10 knots or less, but gusty and more erratic ones cannot be ruled out with any passing thunderstorm. These storm chances become more robust and prevalent during the day Tuesday. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...DJ LONG TERM...GREIF AVIATION...DJ/GREIF
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
627 PM CDT Mon Jul 25 2022 .SHORT TERM... Issued at 243 PM CDT Mon Jul 25 2022 Through Tuesday night... What started as a bright, sunny Monday has now turned mostly cloudy as shower activity picks up to our west and southwest. This rain is forming along a baroclinic zone driven by 30-35 kt low level jet draped across south-central IL. South of the LLJ is stout warm air and moisture advection with an ideal CAPE profile for widespread, soaking rain across the southern half of the state. We will see some of that moisture begin to surge into our CWA later through the evening and overnight, but the instability should stay well to our south through the night keeping thunder chances at bay. Short-range guidance is in great agreement that showers will be passing by just to the south of the CWA later this evening, but whether the rain will actually make it into the CWA, not so much. Based on forecast soundings and upstream observations, it appears likely that at least some scattered showers will be moving across areas south of the Kankakee River valley this evening and overnight. Meanwhile, the rest of the CWA will remain dry but hang onto the cloudy skies. This first round for folks further south could last into mid-morning tomorrow, but most of tomorrow morning and afternoon and will rain- free area-wide. In fact, those north of I-88 may even be able to work in some decent sunshine during the day tomorrow as some drier air will try and sneak in aloft. Tomorrow evening, however, a cold front will begin advancing into the Midwest from the Plains stemming from an occluding Low based up in northern Ontario. Rain chances build from the west into the overnight as the front approaches. There`s a good deal of disagreement among guidance on both thunder chances and rain coverage as a result of this front. The front does not look very potent whatsoever with a less-than-impressive thermal gradient. Ahead of the front, we should manage to build up at least a few hundred, but as many as around 1,200, joules of elevated CAPE. With poor low level lapse rates well agreed upon, the biggest sources of the uncertainty are the height of the LFC and the strength of the forced ascent along the boundary. If we can manage to lift parcels to their LFC, a complex of thunderstorms appears very possible overnight into early Wednesday morning when the front is expected to pass through, though nothing severe is anticipated. The HRRR and FV3 are big fans of this solution, but, then again, they are the only models in the HREF suite that favor updrafts sufficient for thunderstorm development. It`s unclear the exact reason why but the HRRR does have the LFC sitting as low as 850 mb during FroPa which shouldn`t make it too hard to get some convection going given the surrounding environment. Most other models like the idea of just some widely scattered, elevated, convective showers. With ample moisture through the profile, we may see some pockets of heavier rainfall if we can make some good use out of the available instability. But, to wrap it up, at least some rain should be in the area Tuesday night into early Wednesday morning. Doom && .LONG TERM... Issued at 149 PM CDT Mon Jul 25 2022 Wednesday through Monday... Wednesday through Friday, the Great Lakes will be located on the southern periphery of an expansive upper-level low pressure system barreling through central Ontario. Temperatures will hence follow a cooling trend with highs in the lower 80s on Wednesday and the mid to upper 70s on Thursday and Friday. Occasional chances for showers and perhaps a thunderstorm will be present Wednesday through Friday as compact short-wave troughs "pinwheel" through the cyclonic flow aloft. The best shot looks to be on Wednesday before deep-column moisture is shunted south of our area. In other words, most areas Thursday and Friday will probably stay dry. Any thunderstorm that can develop should not be nearly as strong as this past weekend given little opportunity to develop meaningful instability (e.g. poor mid-level lapse rates and decreasing column moisture). Behind the upper-level low, compact upper-level ridging and a surface high pressure system will slide through the Great Lakes this weekend leading to beautiful summer weather. Sunny/clear skies will help highs Saturday and Sunday should climb into the upper 70s to lower 80s. Overnight lows should fall into the 60s. Daily lake breezes appear to be a good bet which will hold lakeshore temperatures a hair cooler than inland. Chances for precipitation may increase early next week as southerly return flow is reestablished on the backside of the surface high pressure system. Blended NBM guidance provides low-end "chance" PoPs (20-30%) as early as Sunday evening, though a quick glance at individual ensemble members suggests a more realistic chance after the start of the workweek. Borchardt && .AVIATION... For the 00Z TAFs... 627 PM...Only forecast concern is wind directions Tuesday. A lake breeze has moved west of ord/mdw this afternoon and may push west of dpa before dissipating this evening. Winds will slowly turn to light southeast later this evening and may become light and variable overnight. Wind directions on Tuesday will be southerly, but low confidence if they will favor south/southwest or south/ southeast. A lake breeze is likely to form Tuesday afternoon but low confidence for how far inland it will move and for now, have not included any easterly shift for ord/mdw. cms && .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
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1059 PM CDT Mon Jul 25 2022 .UPDATE... Issued at 803 PM CDT Mon Jul 25 2022 The flash flood watch that covers our northern counties has been extended further south. Yesterday`s cold front that moved through the CWA into southern Missouri was forecast to return north as a warm front. According to surface analysis and radar data, we can see that the front is remaining fairly stationary if not moving south over southern Missouri. Deterministic guidance has picked up on this, with the RAP and NBM pulling their heaviest QPF further south. Although the axis of heaviest precipitation may be further south than expected, the highest risk of heavy rain still lies in the northern CWA, north of I-70 in Missouri and I-64 in Illinois. This is where the best moisture convergence will be overnight, on the nose of a low level jet that will set up in central and east-central Missouri. The low level jet will help provide additional lift in tandem with the isentropic ascent from the front. As convection initiates along the nose of the jet, it will travel east-southeast across Missouri and west-central Illinois in a line extending from roughly Moberly, MO to Vandalia, IL. Isentropic ascent will play a large role in the heaviest corridor of precipitation tonight, and with the front behaving differently than forecast, the flood watch had to be amended to accommodate these changes. Jaja && .SHORT TERM... (Through Late Tuesday Night) Issued at 245 PM CDT Mon Jul 25 2022 Morning activity continues to weaken as it slides eastward through the region. The main forecast issue in the short term is the increasing chances of showers and storms tonight as a complex develops over southeastern NE/northeastern KS/northwestern MO and slides east across northern half of Missouri. Early tonight the stalled frontal boundary just south of the Missouri/Arkansas border will begin to slowly lift northward as a warm front. In the meantime, a low level jet will develop and veer to the southwest increasing to around 40 to 45kts. With PWATS in excess of 2 inches and increasing WAA as well as isentropic ascent due to the low level jet, expect very efficient rainfall rates with showers and storms that develop on the nose of the LLJ over northwestern Missouri and slide eastward north of the front. A majority of the latest CAMs have ever so slightly shifted the main core of showers and storms a bit further south, but still along and north of the I-70 corridor. Also, the highest axis of qpf extends from Monroe County MO southeastward to Fayette County IL with between one and three inches in this area, though locally higher amounts are possible. So will add one more row of counties on the southern edge to the Flood Watch. As for any severe storms, with the frontal boundary to the south of the complex and weak elevated instability, do not anticipate any severe storms at this time, so we will not be messaging this. On Tuesday, the complex will exit by midday. However, scattered activity is still possible due to lingering outflow boundaries and the front. Temperatures through the short term will remain near normal with lows in the low 60s to low 70s tonight and in the mid 60s to mid 70s Tuesday night. Meanwhile, highs on Tuesday will depend on location of the front, cloud cover and precipitation, so for now highs will range from around 80 far north to the upper 90s far south. Byrd .LONG TERM... (Wednesday through Next Monday) Issued at 245 PM CDT Mon Jul 25 2022 Active pattern will persist through the rest of the work week with several rounds of showers and storms. On Wednesday a more vigorous shortwave will slide through the region with the best chances of showers and storms Wednesday night through Thursday, mainly along and south of I-70. Even though the weekend looks dry, at least on Saturday, the latest ECMWF as well as ensembles are indicating rain chances returning to the region by Sunday. For now stuck with the NBM solution with chance POPs Sunday through Monday. Byrd && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1059 PM CDT Mon Jul 25 2022 Showers and thunderstorms have developed over central Missouri and are moving northeast through central and east-central Missouri. As the low level jet ramps up tonight and provides additional forcing for precipitation, this convection is expected to continue through the overnight hours and into Tuesday morning. All terminals are forecast to be impacted by at least showers by morning, with KUIN, KCOU, KSUS, and KSTL with TEMPO groups for thunder. KJEF and KCPS were left out of this because of their positions south of where thunderstorms are expected to flourish. The best chance to see heavy rain and thunderstorms is early morning Tuesday, with mention of showers being taken out of the TAFs by late morning/early afternoon. Jaja && .PRELIMINARY POINT TEMPS/POPS... Saint Louis 67 89 75 90 / 90 70 50 50 Quincy 63 80 69 84 / 90 60 40 40 Columbia 66 92 71 89 / 70 40 60 50 Jefferson City 69 93 72 90 / 50 40 60 40 Salem 66 86 73 87 / 90 90 50 60 Farmington 70 94 73 91 / 30 30 40 60 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...IL...&& $$ WFO LSX
Area Forecast Discussion
National Weather Service Melbourne FL
931 PM EDT Mon Jul 25 2022 .DISCUSSION... Current-Tonight...Diurnal convection has ended across the interior this evening and now the focus will turn towards the local coastal waters with onshore moving convection a possibility overnight across the Treasure Coast. Realistically, cannot rule out an ISOLD shower northward along the coast as well. Primary threats remain occasional lightning, brief downpours, and locally gusty winds. Weak upper trough pushing across the peninsula westward with some cooler temps aloft (-9C at 500mb). Else, PCloudy skies with deep ESE flow. Lows in the M70s, with U70s along the immediate coast. Tuesday...Previous Modified...Unfortunately, lower confidence has returned, with large disagreements in the models for PoPs. Despite continued higher moisture (up to 1.8-2.1" from north to south according to the GFS), the GFS is once again the extreme dry outlier for PoPs (around 20% across the northern interior) compared to the ECS (around 40%) and the NBM (up to 60-70%). The long range HRRR is once again more on par with a ECS solution, so have opted for a forecast similar to this. Based on convection from this past afternoon, this looks like the most likely solution. Despite the discrepancies for areas from around Orlando/Kissimmee northward, model guidance is at least in agreement on higher PoPs (50-60%) inland from the Treasure and southern Space Coasts. Though, this may be a bit overdone, if the GFS is correct. Overall, PoPs around 30- 45% for the rest of the area, with showers and a few storms drifting onshore, mainly from the Cape southward, during the morning hours once again from the Atlantic. East to southeast flow looks to continue, increasing to around 10-15 mph behind the sea breeze as it pushes inland. Highs reaching the lower to mid 90s. && .AVIATION...Generally VFR conditions throughout the night at all TAF sites, with isolated convection possible along the Treasure Coast TAF sites through the early morning. Will add TEMPO groups as necessary. VCTS starting around 14Z at the Treasure Coast, with a potential need for some TEMPOs for MVFR conditions. Interior sites will see VCTS conditions from 18-23Z tomorrow. Lower confidence for VCTS affecting northern coastal sites right now, so made it VCSH for the 17-21Z time period. Winds primarily out of the SE around 7-12 kt tomorrow. && .MARINE...Overnight-Tue...Generally favorable boating conditions with ESE/SE winds 10-15 kts. Seas 3-4 ft. Scattered showers and isolated lightning storms occasionally drifting onshore. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ Sedlock/Weitlich/Tollefsen/Law
Area Forecast Discussion
National Weather Service New York NY
1118 PM EDT Mon Jul 25 2022 .SYNOPSIS... A cold front moves through the area tonight, stalling south of the area on Tuesday. Weak high pressure builds in from the Midwest behind the front into midweek. A frontal system approaches Wednesday night and moves across Thursday into Friday. High pressure then returns, building in from the west heading into next weekend. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... Just a slight chance of showers is expected overnight as the cold front moves through the forecast area. Though a stray thunderstorm is possible over the next couple of hours, did not mention thunder as any thunder that has been occurring over the last few hours has been outside for the forecast area. Progressively drier and a bit cooler airmass advects in behind the cold front tonight. Lows will be in the middle 60s to low 70s. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... Behind the frontal passage, surface high pressure from the Great Lakes slides east on Tuesday, helping advect drier wind with northwest flow. Clouds linger however, especially across the southern half of the region, with the front stalled just to our south. This creates a bit of uncertainty later in the afternoon as a weak area of low pressure develops along the front. Guidance has kept the bulk of any associated rain to the south, though the 18z HRRR indicates a batch of showers making it into NYC and Long Island. Will need to monitor trends overnight, but currently treating this as an outlier, maintaining only a slight chance (<15%) through Tue night. High temperatures return closer to normals for this time of year, with most areas expected to top out in the mid 80s. The drier air allows for lower humidity, helping it feel much more comfortable outside. Lows Tuesday night fall into the mid 60s to low 70s. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Large upper level low opening up to a trough takes place in the long term over the Northeast. At the surface, weak high pressure during midweek gives to an approaching frontal system Thursday into Friday. High pressure then returns, building in from the west for the weekend. Chances for rain showers from time to time mid to late week. Mainly dry conditions expected for the weekend. Chances for thunderstorms Thursday into Thursday evening with daytime increase in surface instability. Temperatures forecast to stay above normal for highs. Upper 80s to lower 90s generally expected for forecast highs with hottest day forecast to be Thursday, when highs get more into the 90s with low to mid 90s across Northeast NJ. Thursday is also a day where it is forecast to be humid enough for forecast heat indices to reach low to upper 90s across the region. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... A cold front moves tonight. The front stalls south of the region tonight into Tuesday. Mainly VFR. Much of the activity in regards to showers should stay north of the metro terminals. However still cannot rule out a shower as the cold front moves through. S to SW winds shift to the W then NW overnight, then back toward the W Tuesday morning. There may be some sea breeze enhancement for coastal terminals, shifting wind directions toward the SW late Tuesday morning into the afternoon. Wind speeds of around 10 kt or less are expected through the TAF period, with light and variable conditions possible at the outlawing terminals. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled amendments expected. .OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY... .Tuesday night...Mainly VFR. Low chance of MVFR or lower in slight chance of showers. .Wednesday...VFR in the morning, then a chance of showers in the afternoon and at night with MVFR possible. .Thursday...Chance of MVFR in showers and thunderstorms. .Friday...VFR. A chance of showers, mainly in the morning. .Saturday...MVFR possible in morning showers. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... SCA winds across the ocean expected to diminish below SCA by midnight, with SCA seas continues until 15z Tuesday morning for the western ocean and 00z Tuesday evening for the two eastern ocean zones given slow subsiding of 6 to 9 ft southerly swells below 5 ft. Non- ocean waters remain below SCA criteria. Thereafter, conditions on all waters generally remain below SCA thresholds through the weekend. && .HYDROLOGY... Flash flood threat has ended. No significant widespread heavy rain is expected Tuesday through the upcoming weekend, at this time. && .TIDES/COASTAL FLOODING... A high risk of rip currents is expected to extend into Tuesday due to lingering 5ft@8 sec southerly swells. There is a moderate rip current risk Wednesday for all Atlantic facing beaches from a combination of 2 ft S and SE swells. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...High Rip Current Risk through Tuesday evening for NYZ075-080- 081-178-179. NJ...None. MARINE...Small Craft Advisory until 11 AM EDT Tuesday for ANZ355. Small Craft Advisory until 8 PM EDT Tuesday for ANZ350-353. && $$ SYNOPSIS...JM/DR/MW NEAR TERM...JP/DR/NV SHORT TERM...DR LONG TERM...JM AVIATION...JP MARINE...JM/DR/MW HYDROLOGY...JM/DR/MW TIDES/COASTAL FLOODING...
Area Forecast Discussion...UPDATED
National Weather Service Springfield MO
629 PM CDT Mon Jul 25 2022 Key Messages: 1. Isolated thunder possible this evening. 2. Heat Advisory posted again tomorrow for most areas. 3. Continued isolated to scattered thunderstorm chances through the week as a slow moving frontal system passes through the region. 4. Cooler temperatures by Thursday, and continuing through the upcoming weekend. Could experience more rain chances through the weekend as well. .SHORT TERM...(This evening through Tuesday) There could be an opportunity for a couple of pulse thunderstorms late this afternoon and this evening as the RAP supports an environment possible for convection. PWATS in the 1.55 to 1.90 inch range combined with sufficient mid level moisture and reduced inhibition could lead to a few updrafts. This will need to be monitored closely as mixed layer capes have increased to 2500 to 3000 j/kg east of Springfield. Another complex of thunderstorms is expected to develop tonight across northern Missouri as most of this will not impact our forecast area. Due to this complex staying north, a hot day is expected for Tuesday with readings back into the triple digits for many locations. Therefore a Heat Advisory has been posted for all counties except for a few up in central Missouri. Isolated convection will be possible on Tuesday as well, although, coverage is expected to remain low. .LONG TERM...(Wednesday through Monday) Dry air at the surface is expected to raid southern Missouri, causing instability levels to be limited for thunderstorm activity on Wednesday afternoon. While the surface front is expected to slowly drift southward, this will eventually lead to increased coverage of thunderstorms. Wednesday night into Thursday looks to be the best window of opportunity for some much needed rainfall across southern Missouri. This frontal system will also bring an end to the current heat wave. Afternoon high temperatures Thursday into the weekend will be limited to the 80s on a daily basis. However, the surface front remain hung up over Arkansas, which should yield additional precipitation chances over southern Missouri through the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 626 PM CDT Mon Jul 25 2022 Confidence is high that VFR conditions will prevail through the TAF period. There is a very small chance for a shower or storm tonight and again tomorrow afternoon however its too low to include in the TAFS at this time. Winds will remain southerly with increasing gusts again on Tuesday. Low level wind shear is likely tonight at all three sites. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...Heat Advisory until 8 PM CDT this evening for MOZ066-077>079- 088>097-101>106. Heat Advisory from 11 AM to 7 PM CDT Tuesday for MOZ066>071- 077>083-088>098-101>106. KS...Heat Advisory until 8 PM CDT this evening for KSZ073-097-101. Heat Advisory from 11 AM to 7 PM CDT Tuesday for KSZ073-097-101. && $$ SHORT TERM...Cramer LONG TERM...Cramer AVIATION...Burchfield
Area Forecast Discussion
National Weather Service San Diego CA
904 PM PDT Mon Jul 25 2022 .SYNOPSIS... Monsoonal moisture will maintain at least slight chances for thunderstorms each afternoon and evening this week. Slightly higher chances for storms are anticipated again Friday through Sunday with the approach of another easterly wave. The monsoonal moisture and enhanced cloud cover will continue to favor cooler than average days most areas this week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Satellite imagery at 8 PM PDT indicated patchy high clouds drifting from SE to NW across SoCal, and a solid layer of marine stratus offshore and well into coastal areas. There were still a few lightning strikes south of the International Border, and in western AZ, but the skies were quiet over our forecast area. Our 00Z Miramar sounding had an 8C inversion based near 2K FT. This was nearly 500 feet lower than yesterday afternoon. The latest WRFEMS and HRRR runs show less convection developing tomorrow afternoon, so likely not as active a day. Little else will be changing. The forecast was updated earlier to remove the Flood Watch. No other changes are planned. From previous discussion... Monsoonal moisture remains in place on Tuesday with another slight chance of showers and thunderstorms over mountainous terrain. Storm coverage on Tuesday is expected to be slightly less than today owing to the lack of any midlevel disturbances providing extra lift, and this trend is reflected in hi-res guidance. Midlevel ridging will build in over the Great Basin through the middle and latter portions of this week. The positioning of the ridge will still allow for easterly flow and middle and upper levels to remain in place, favoring additional monsoonal moisture to support at least slight chances for showers and thunderstorms each day through the week ahead. Another easterly wave may approach the area on Friday, supporting slightly higher chances for showers and storms over the mountains. A majority of EPS/GEFS members have at least some degree of measurable precipitation at Big Bear Friday through Sunday, lending more confidence to thunderstorm chances being slightly higher than depicted by current NBM guidance. Outside of daily monsoonal convection, temperatures slightly below seasonal normal can be anticipated through much of this week over the mountains and deserts as a result of building monsoonal moisture and enhanced cloud cover. Near the coast, prolonged onshore flow will keep the marine layer inversion fairly strong, which will support low-level clouds late each night and morning. Most areas from the coast all the way to the deserts will see highs anywhere from 2 to 5 degrees below seasonal normal as a result of these factors. && .AVIATION... 260310Z...Coast/Valleys...Low clouds along the immediate coast will move inland tonight. Bases will be around 1200-1500 feet MSL extending into portions of the inland valleys by 14Z Tue, but not quite as far as this they did this morning. Scatter out Tuesday 16- 18Z, with only partial clearing at immediate coast. Mountains/Deserts...SCT-BKN high clouds AOA 12000 feet MSL through Tuesday. ISO-SCT TSRA Tuesday afternoon. && .MARINE... No hazardous marine weather is expected through Saturday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...10/Adams AVIATION/MARINE...PG
...Update to aviation forecast discussion...

.DISCUSSION... Issued at 239 PM CDT Mon Jul 25 2022 Key Messages: - Additional showers and storms expected tonight with best chances along and north of Interstate 70. - A break from the summer heat continues through the weekend with periodic chances for showers and storms. Broad upper ridging remains over the southern CONUS with zonal flow present across the central Plains. At the surface, high pressure has settled into the mid and upper Mississippi Valley with the front that passed through yesterday having stalled across southern Kansas. A weak perturbation in the zonal flow has provided enough lift for some elevated showers to continue for portions of northeast Kansas this afternoon. Modest capping and a lack of forcing will likely preclude convective initiation this afternoon, although the HRRR has been persistent in developing a storm or two along the aforementioned surface front. If storms develop, they would likely remain south of the forecast area given the location of the front, but they could sneak into the southern portions of the CWA. Showers and storms are more likely overnight as the LLJ increases isentropic ascent across the area. CAMs are in decent agreement and depict storms initiating between 02- 04z for mainly areas along and north of Interstate 70. Some of these storms could be strong to severe and produce damaging wind gusts. Heavy rain is also possible given PWAT values at or exceeding 2" and storm motion parallel to the 925-850mb front, possibly leading to back-building and training storms. HREF members are highlighting areas in far northeast Kansas with having the best chance to see heavy rainfall overnight where a 1.5-3.0 inch axis of heavy rain could fall. This area missed out on the heaviest rains last night and FFG remains on the high side, so the flooding potential isn`t overly concerning. Showers and storms may linger into the early morning Tuesday, but a break in precipitation looks likely after sunrise. The surface boundary lifts back north during the day Tuesday with temperatures warming into the low 90s south of the boundary while areas to the north remain in the 80s. This boundary looks to be the focus for more showers and storms to impact the area Tuesday afternoon through Wednesday morning. The daytime hours on Wednesday look to be mainly dry before additional showers and storms develop as a stronger wave and cold front push through Wednesday night into Thursday. Not expecting much in the way of hazards with these rounds of storms, but with PWAT values forecast to be near climatological maximums for this time of year, flooding may become more of a concern with each successive round of precipitation. Guidance suggests the cold front will push far enough south to create a couple of very nice days Friday and Saturday with highs in the upper 70s to mid 80s with low humidity. The best precipitation chances are shunted south of the forecast area, but can`t rule out some showers and storms Friday and Saturday. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 652 PM CDT Mon Jul 25 2022 MVFR cigs attempt to scatter between 00Z and 04Z before filling back in as additional showers and TSRA develop. Latest guidance develops activity near or just north of KTOP/KFOE so added prevailing SHRA and VCTS aft 04Z. If heavier bands develop over terminals, IFR is anticipated. ATTM...MVFR is more the likely scenario and should lift to VFR by early afternoon. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Flanagan AVIATION...22