Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/11/21

Area Forecast Discussion
National Weather Service Quad Cities IA IL
600 PM CDT Fri Sep 10 2021 ...00Z AVIATION UPDATE... .SYNOPSIS... Issued at 158 PM CDT Fri Sep 10 2021 High pressure is moving off of the area this afternoon, but remained in place long enough for dry air to remain in place today. Temperatures are increasing, but still in the 70s north to lower 80s south today. Dewpoints are in the mid 50s north to around 60 south, and with southeast winds, these will be slow to increase tonight. The heat is well established over the western and southern Plains, as well as eastern Rockies. While this will surge towards the area over the next couple days, so will the extensive wildfire smoke, easily seen on visible satellite over the Dakotas through western Iowa. I`m definitely seeing that smoke having an negative impact on temperatures and that is something that could derail our hot weather forecast tomorrow. && .SHORT TERM...(This Evening through Saturday) ISSUED AT 158 PM CDT Fri Sep 10 2021 Great Plains smoke is forecast to increase over our area tonight and peak Saturday, which is explicitly shown in the HRRR vertically integrated smoke output. Smoke will not have any impact to tonight`s lows, which will range from the upper 50s north to the lower 60s central and south. Smoke will certainly impact our temperature forecast Saturday. With the HRRR forecast, we could see highs in the mid to upper 80s over the area, while the 90s hold over the west half of Iowa. I`ll stay with the NBM, which is cooler than prior runs and accounts for the expected deep mixing, and lower dewpoints that southwest flow should provide. All in all, apparent temperatures in the lower 90s should be paired with a 10 to 15 kt southwest wind. That`s not so bad, and represents a typical late summer heat wave rather well. Dry conditions are confidently forecast through Saturday. ERVIN .LONG TERM...(Saturday Night through Friday) ISSUED AT 158 PM CDT Fri Sep 10 2021 [Key Messages] *Periodic chances of showers & storms through late next week *Above normal temperatures favored [Discussion] Our pleasant, dry northwest flow is progged to break down over the later part of the weekend as zonal flow takes over. Southerly flow at the surface will continue to usher in a warm, humid air mass into the area characterized by daily highs near 90 and lows in the upper 60s to low 70s. Beginning Saturday night, a warm front is progged to develop near the IA/MN border, with slight meandering to the south near to the DVN/ARX border Sunday. This front will serve as a convergence zone for isolated to scattered showers and thunderstorms from Sunday afternoon through Tuesday. Deterministic and ensemble guidance is in good agreement of the greatest coverage likely remain to the north of the CWA border, where the best lift from WAA and moisture will take place. A better chance for showers and storms will occur PM Tuesday as a surface low tracks along the front and bring a cold front across the area. With instability forecast to climb into the 1500-2500 J/kg range, there is some potential for strong storms. However, the severe threat this time appears to be low with stronger shear displaced to the north and west. Much cooler air will follow behind the front, with temperatures Wednesday and Thursday returning to values we`ve seen over the past few days. Beyond Thursday, guidance remains varied on solutions. The GFS advertises high pressure quickly moving through the area with an abrupt return to southerly flow, very warm temperatures and diurnal precip chances. Meanwhile, the ECMWF and CMC take the high slowly through the area with a delay on the warm-up. Regardless of the solution, the overall consensus remains that above normal temperatures will be sticking around for some time with a ridge of high pressure remaining stagnant across the southeast U.S.. && .AVIATION...(For the 00Z TAFS through 00Z Saturday Evening) ISSUED AT 600 PM CDT Fri Sep 10 2021 Predominantly VFR expected through the TAF period. River valley fog is possible overnight, but confidence on impacts at the terminals is too low for any mention. Otherwise, high level smoke will persist along with some mid/high clouds at times. Winds look to increase from the south/southwest Saturday due to mixing, with gusts 15-20 kts by afternoon. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Ervin SHORT TERM...Ervin LONG TERM...Speck AVIATION...McClure
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
626 PM CDT Fri Sep 10 2021 .AVIATION... VFR flying conditions prevail tonight through Saturday evening. Only a FEW MVFR level clouds possible early to mid Saturday morning. VRBL mainly easterly winds around 5 KTs or less tonight become E-SE 5 to 10 KTs on Saturday. A few gusts to 17 KTs possible Saturday afternoon. && .PREV DISCUSSION... /ISSUED 230 PM CDT Fri Sep 10 2021/ SHORT TERM (Tonight through Saturday Night)... Midday RAP analysis depicts a 597dm ridge centered over northern New Mexico. Aloft, some wildfire smoke overhead is making for a hazy- looking sky, but this should slowly dissipate from east to west through tonight per HRRR-smoke output. Easterly flow at 850mb is noted today, with GOES TPW product showing a maxima of 1-1.25" over the Coastal Plains, coincident with an area of diurnal cumulus development. Also shown in the GOES TPW is a broad region of rather dry air across far SE TX, S LA, and into MS/AL with values <0.7". This region is forecast to push into south-central Texas late tonight and through tomorrow, which will keep conditions calm and dry and allow our eastern locations to see another cool morning. Anticipating another day of near to above normal highs Saturday. Then on Saturday night boundary layer flow will veer to the SE/S and a much more moist airmass will begin to move in. PWATS increase to 1.5" or greater over our southern counties by 12Z Sunday. We don`t anticipate any precipitation through Saturday night. LONG TERM (Sunday through Friday)... We will be watching the southwestern Gulf of Mexico at the beginning of the long-term forecast as a disturbance is expected to slowly move north off the coast of Mexico on Sunday. Models are in fairly good agreement that some organization into a possible weak tropical cyclone will occur with this system as upper level conditions are somewhat favorable for development. The latest Tropical Weather Outlook from the National Hurricane Center gives this system a 70 percent probability it will form into at least a depression in the Sunday-Tuesday time frame. While models are in good agreement that this system should remain weak, the track of this system is highly uncertain as with any system that has not formed a closed low yet. This morning`s run of the GFS brings it inland over Mexico while the 12 ECMWF rides it just off the coast eventually moving it just west of Houston. Most ensemble members support the eastward end of the envelope. If the preferred solution were to occur, most of the heaviest rainfall would remain to our east with just the eastern portions of the area possibly getting decent rainfall with the remainder of the CWA perhaps only seeing scattered activity. However, if the deterministic run of the GFS were to verify, most of the area could see decent rainfall Tuesday and Wednesday. Continue to receive updates from trusted sources on the evolution of the forecast through the weekend. Confidence will remain low until a closed surface low does develop. Lower rainfall chances should linger into Thursday and Friday, but overall chances will continue to hinge on what occurs for the first half of the long-term forecast. Otherwise, the increase in moisture and cloud cover should keep highs possibly in the upper 80s to lower 90s for most locations for much of the long- term forecast period. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 66 95 70 92 74 / 0 0 0 20 30 Austin Bergstrom Intl Airport 64 95 68 92 72 / 0 0 0 20 30 New Braunfels Muni Airport 66 95 68 91 72 / 0 0 0 20 30 Burnet Muni Airport 65 92 67 90 71 / 0 0 0 10 20 Del Rio Intl Airport 72 99 72 95 74 / 0 0 0 10 10 Georgetown Muni Airport 65 94 68 93 72 / 0 0 0 10 30 Hondo Muni Airport 68 94 70 92 72 / 0 0 0 20 30 San Marcos Muni Airport 65 95 67 91 71 / 0 0 0 20 30 La Grange - Fayette Regional 64 95 71 92 74 / 0 0 0 40 40 San Antonio Intl Airport 68 94 71 91 74 / 0 0 0 20 30 Stinson Muni Airport 69 96 72 92 75 / 0 0 0 20 30 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term/Aviation...04 Long-Term...Oaks
Area Forecast Discussion
National Weather Service Green Bay WI
1055 PM CDT Fri Sep 10 2021 Updated aviation portion for 06Z TAF issuance .SHORT TERM...Tonight and Saturday Issued at 223 PM CDT Fri Sep 10 2021 The latest RAP analysis and satellite/radar imagery show high pressure stretching from the central Great Lakes to the Gulf Coast. Fair weather cumulus clouds are present across much of northeast Wisconsin early this afternoon. Other than a smattering of mid and high clouds, skies are mostly clear upstream across the Dakotas and Minnesota where a warm front is sliding east. As a shortwave across central Canada pushes a cold front into the region on Saturday, thunderstorm and severe potential are the main forecast concerns. Tonight...A warm front will move across the area from the west, but the airmass will remain very dry, and too dry for any precip chances. Strengthening low level wind fields should prevent much in the way of ground fog from developing. Lows will be more mild and range through the 50s to near 60 by Lake Michigan. Saturday...Digging shortwave energy will move into the Lake Superior region while pushing a cold front across northern Wisconsin in the afternoon. The airmass will remain quite dry across the region at the start of the morning, but should see dewpoints rise into the low to mid 60s ahead of the front. This will lead to surface based instability rising to around 2000 j/kg across central and east-central WI during the afternoon. But despite the presence of good convergence and instability ahead of the front, rising heights aloft in combination with strong capping centered around 800-750 mb will make it quite difficult to achieve sustained updrafts and convective initiation. Have added a slight chance to central and east-central WI after 4 pm in case an updraft can break through the cap. If this were to occur, deep layer shear of 40-50 kts and mid-level lapse rates of 7 to 7.5 C/km could lead to a large hail and damaging wind threat. Warmer temps with highs in the mid 70s to mid 80s. .LONG TERM...Saturday Night Through Friday Issued at 223 PM CDT Fri Sep 10 2021 A surface cold front will continue sinking south Saturday night, which could set off some showers and thunderstorms across the region. The main question continues to be if the capping inversion in place can be overcome. If storms can fire, they would be fairly isolated in nature, which is evidenced by the very sparse coverage of convection on the CAMS models, if they have any convection at all. Any storms that do form have the potential to be strong to severe across central and east-central Wisconsin with MUCAPEs of 1000 to 2000 J/kg and bulk shear values around 40 knots. The main threat would be large hail and damaging winds given the inverted-V soundings with abundant low level dry air. Confidence in storms developing is still fairly low with this forecast; therefore, kept the POPs during this period in the slight chance range. The aforementioned cold front will stall across southern Wisconsin Sunday into Monday, which could generate additional showers and thunderstorms across the region as several shortwaves track along the stalled out boundary. The main threat for rainfall would be across central and east-central Wisconsin closer to the surface boundary itself. The severe threat during this period appears to be fairly low given the area will be north of the frontal boundary as instability will be fairly meager. Temperatures Sunday and Monday will drop significantly behind the cold front, falling to below normal levels for this time of year. There will be a better chance for widespread showers and thunderstorms Monday night into Tuesday as the stalled out front lifts north as a warm front Monday night, with the attendant cold front sweeping through on Tuesday. Although the threat for severe weather is a bit more difficult to ascertain during this period, the strong dynamics associated with this system indicate that strong storms and heavy rainfall are possible. As the system gets closer and timing becomes clearer, the severe weather threat will be easier to diagnose. High pressure will build in behind this system, with dry weather expected on Wednesday and Thursday. Another low pressure approaching the region from the west could bring some showers and thunderstorms to northern Wisconsin by next Friday. && .AVIATION...for 06Z TAF Issuance Issued at 1054 PM CDT Fri Sep 10 2021 Good flying conditions anticipated through this TAF issuance. High clouds will pass through the area overnight through the day Saturday. The best chance for seeing mid cloud development will be Saturday afternoon as a cold front sags south through the area. Models continue to be very anemic with regards to developing convection. Only a few isolated showers or thunderstorms are anticipated and they may not impact the TAF sites. After any storms in the early evening, expect quiet conditions late in the evening and overnight. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......Kurimski AVIATION.......Cooley
Area Forecast Discussion
National Weather Service Lincoln IL
844 PM CDT Fri Sep 10 2021 .SYNOPSIS... Issued at 252 PM CDT Fri Sep 10 2021 The stretch of dry weather will continue through this weekend as temperatures exhibit a warming trend. Afternoon highs will surge into the lower 90s beginning Saturday, with the potential for these seasonably warm temperatures to extend through Monday. A cooler and wetter pattern will return by mid-week and extend through the remainder of next week. && .UPDATE... Issued at 844 PM CDT Fri Sep 10 2021 Scattered mid clouds are across the area this evening and will continue into the overnight hours. Winds have become more southeast and believe this is allowing temps to drop a little bit more than forecast. So will make some adjustments to overnight low and hourly temps and try to get cloud cover more in-line with reality. Update to the forecast will be out shortly. && .SHORT TERM...(This evening through Sunday) Issued at 252 PM CDT Fri Sep 10 2021 Skies remain clear this afternoon as an upper-level ridge and its attendant surface high pressure build across the Great Lakes region. High pressure will gradually drift into the Mid-Atlantic region this evening in response to a strong mid-level shortwave digging across the Canadian Prairies. Low-level winds will begin to veer southwesterly across Central Illinois as surface high pressure departs eastward. The net effect will be warming temperatures into the weekend as 21-23C 850-mb air advects into the region from the Southern Plains. This should correspond to surface temperatures in the lower 90s both Saturday and Sunday. This kind of heat is unusual for the season, but not record-breaking. It should also be noted that despite the very warm temperatures, heat index values will be held down by surface dewpoints in the 60s. Skies will become more milky in appearance by Saturday morning as smoke from the wildfires out west makes its into our region. Latest HRRR guidance suggests this smoke will stay most concentrated in the layer 6,000 ft AGL, which should mitigate near surface smoke/haze and its associated air-quality concerns. .LONG TERM...(Monday through Friday) Issued at 252 PM CDT Fri Sep 10 2021 Well above normal temperatures will continue into Monday and Tuesday as a frontal zone gets hung up just north of I-80. Afternoon highs will warm into the upper 80s each day as overnight lows cool into the mid- to- upper 60s. The next best chance for rain still looks to be Tuesday into Wednesday as shortwave energy lifts into the Upper- Mississippi Valley and helps drive a surface cold front into central Illinois. It`s not clear yet whether thunder will accompany this front, as CAPE/shear profiles look underwhelming, but we went with a chance mention of it in our forecast grids. Temperatures will come down near their normal values with the arrival of the front, with daily highs near 80 degrees and overnight lows near 60. Additional light rain showers will then be possible Thursday into Friday as the surface front drifts northward in response to a tropical disturbance lifting northward out of the Gulf. Deterministic models and their ensemble clusters have yet to clearly resolve this late week rain potential, so we`re only mentioning a slight chance in our forecasts at this juncture. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 710 PM CDT Fri Sep 10 2021 VFR conditions will continue at all TAF sites next 24hrs. Scattered AC will move across the sites this evening into the overnight hours from the west/northwest and then dissipate during the overnight hours from west to east. Smoke will remain an issue tomorrow as well. Winds will be southerly this evening and overnight and then become south-southwest tomorrow at 10-15kts. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Auten SYNOPSIS...MJA SHORT TERM...MJA LONG TERM...MJA AVIATION...Auten
Area Forecast Discussion
National Weather Service Marquette MI
622 PM EDT Fri Sep 10 2021 .SHORT TERM...(This evening through Saturday) Issued at 419 PM EDT FRI SEP 10 2021 Water vapor imagery and RAP analysis show a mid-level ridge over the Rockies into the Plains. Rounding the ridge, a rather vigorous shortwave over Saskatchewan/Manitoba will be the feature of interest for the short term as it moves to northern Ontario on Sat. Closer to home, it`s been a pleasant aftn. Temps have risen into low/mid 70s F for much of the fcst area. Quite a bit of cu has developed, and there was even a brief -shra s of Newberry recently along the Lake MI lake breeze boundary. Aformentioned shortwave will shift ese tonight, crossing into northern Ontario late tonight with associated cold front reaching western Lake Superior. In response, a 25-35kt low-level jet will translate across the fcst area tonight into Sat morning. Low-level jet will bring increasing theta-e as well as instability for parcels lifted from near or above inversion. There is quite a range of CAPE for those parcels (originating somewhere in the 1-2km layer), ranging from just a few hundred j/kg to near 1000j/kg. With estimated effective deep layer shear of 30-40kt, there would be some storm organization under the higher CAPE values with potential for a couple of strong storms (hail risk). RAP runs thru the morning/early aftn support the lwr end for instability. So, don`t anticipate any svr storms tonight. Best chc of elevated convection later tonight would n and ne of Upper MI, closer to the shortwave/better dynamics. Isentropic ascent is more likely to lead to a better chc of saturation farther n and e as well. Difficult to say how far s convection may develop, but will maintain the general look of previous fcst which matches fairly well with the majority of the 12z model guidance and hourly RAP/HRRR runs from this morning/early aftn. Fcst will reflect slight chc pops across northern Upper MI late tonight, then schc to chc pops shifting to the e half of Upper MI on Sat. Highest pops will be out across Lake Superior. With 850mb thermal ridge of +15C reaching Upper MI late tonight ahead of the cold front and with increasing sw winds later tonight (10-20mph gusting to 25mph along downsloping areas near Lake Superior), temps in downslope areas near Lake Superior will remain in the 60s F tonight. Over the interior w half where winds remain more decoupled, temps will fall into the low/mid 50s. Cold front will continue moving across the area on Sat. So, there is the question of whether any sfc based convection will occur prior to passage of the cold front. There is good model consensus for deep layer shear to be strong at 60+kt. However, there is much more uncertainty on potential MLCAPE, ranging from a few hundred j/kg upwards to 1000-1500j/kg. For the lower end MLCAPE values, there would likely be too much shear to allow convection to get going and become sustained. If the higher end MLCAPE works out, organized storms and a svr risk would be there. Models with the higher MLCAPE paint the highest values over far s central Upper MI, so that would be the area to watch for MLCAPE trends Sat aftn. Given the mild start to the day with 850mb thermal ridge over the area, followed by only modest caa thru the day, expect high temps on Sat in the 70s F. Areas across central Upper MI that see downsloping under westerly winds may top 80F, especially s central. .LONG TERM...(Saturday night through Friday) Issued at 336 PM EDT FRI SEP 10 2021 Medium range models are in fairly decent agreement in the large- scale pattern through the longterm period. As the wern CONUS ridging and ern CONUS troffing pattern breaks down this weekend, a zonal and more progressive pattern will be in place to start the week. There will be several perturbations in this zonal flow with a series of shortwave ridges and trofs throughout this upcoming week. The next chance for pcpn will come early Tuesday morning, before bcmg dry during the middle of the week, with another chance at pcpn towards the weekend. Saturday night, heights will begin to rise behind an existing wave to the NE. 850mb temps won`t cool off too much behind the pass cold front as a very tight gradient is progged to remain over the UP, with temps neat 5C in Copper Harbor and closer to 13C in Menominee. This will bring temperatures to around 70 across the interior with upper 60s along the lake, otherwise it will be a fairly quiet day. This temperature gradient will linger across northern Wisconsin on Monday as a shortwave trof is progged to shift from the Pac NW through the northern CONUS into Canada. Monday evening into Tuesday morning, a 30kt LLJ will lift through this front, bringing WAA and rain across the Upper Great Lakes and UP. At this point, I left thunder out of the fcst as instability will be elevated due to nocturnal WAA, and CAPE seems marginal at this time. A sfc low develops to the north of Superior, which could help bring in some cooler temps for Wednesday, but this would be rather short-lived if at all with ridging and SW winds moving in quickly Wednesday evening. Another ridge will move in behind this trof, bringing rising heights and drying conditions Tuesday evening into Wednesday. Behind this ridge is another shortwave moving across the northern Rockies. While this is about where deterministic models begin to diverge as well as GEFS spaghetti plots, models suggest an overall similar pattern with this trof making its way towards the UP by Friday. GFS is rather aggressive as a sfc low spins up in northern Ontario before another secondary wave lives through the UP Friday night. EC has only one wave that moves through Friday night as well, taking on a bit of a negative tilt to it as it shifts east of Superior. All in all, Friday into Saturday seems like the next better chc of pcpn but will take a couple more cycles to work out the details. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 622 PM EDT FRI SEP 10 2021 Expect VFR conditions to prevail at KIWD/KCMX/KSAW thru this fcst period. Scattered shra/tsra may develop ahead of a cold front moving se across the area late tonight and Sat, potentially clipping KCMX or KSAW. However, confidence in occurrence/coverage is too low at this point to include a mention in fcst. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 419 PM EDT FRI SEP 10 2021 Approaching cold front will lead to increasing s to sw winds across Lake Superior tonight. Expect gusts to reach 20-25kt with gusts to 30kt possible at some high obs platforms. Cold front will sweep across Lake Superior on Saturday. With a weaker pres gradient in the wake of the front, w to nw winds behind the front will be weaker than the southerlies ahead of the front. Expect postfrontal wind gusts to 20kt. Winds will diminish Sat night and will be under 15kt on Sun as high pres ridge builds se to Lake Superior. These lighter winds will linger into at least Mon morning. Expect some increase in winds later Mon as next low pres trof approaches. That trof will cross Lake Superior on Tue. Gusts may reach 20-25kt at times Mon night/Tue. W to nw winds will increase a little more Tue night/Wed morning with more frequent/widespread gusts to 20-25kt expected. Winds will then diminish w to e later Wed/Wed night. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...JAW AVIATION...07 MARINE...Rolfson
Area Forecast Discussion
National Weather Service Pocatello ID
221 PM MDT Fri Sep 10 2021 .SHORT TERM...Today through Monday. An upper level low moves through the area this afternoon into tomorrow morning. Expect scattered showers and thunderstorms this afternoon into early evening. Small hail and lightning are expected. The biggest impact will be winds of 25 to 35 mph with gusts of 50 mph plus with stronger thunderstorms this afternoon into the early evening. We are in a marginal risk for severe thunderstorms for this afternoon into evening for severe thunderstorms with winds greater than 58 mph. The first wave of thunderstorms is hitting Burly currently look at radar imagery and a second wave or line of thunderstorms is back by Gooding Idaho. A third line, which likely will be mostly showers and weaker when it hits us, is back on the Idaho/Oregon line currently. Lingering showers are expected into Saturday for our eastern areas especially along the Wyoming border, with chances decreasing throughout the day. Saturday night again offers some slight chances for some showers and isolated thunderstorms for the southeast highlands, driven by unstable conditions persisting along the Utah border. Temperatures Saturday cool by about ten degrees associated with a more west/northwest flow. This brings more seasonable conditions back for the period and the start of next week. An upper level trough works through Northern Montana for Sunday into Monday, bringing chances for isolated rain showers and thunderstorms for the Eastern and Southern Highlands, with minimal impacts expected. Wyatt && .LONG TERM...Tuesday through next Friday. Expect an overall low impact period with overall dry conditions and periodically breezy afternoons. Tuesday will be slightly breezy in northwest flow. Wednesday into Thursday a dry trough passes over northern Idaho. Wednesday and Thursday each afternoon expect near critical relative humidity and near critical winds, especially for the Central mountains and the Arco desert areas. Models show another system late Thursday into Friday with moderate winds and light precipitation across our northern areas. Expect 70 to 80s with cooler mountain temperatures through the period. Wyatt && .AVIATION...Gusty winds and showers/storms are beginning to develop across eastern Idaho. Winds in the 15-25 kt range, with higher gusts, seem probable through about 11/02Z. After this time, gradient winds will subside but thunderstorm outflow wind potential will continue. Expecting thunderstorm potential to increase over the next few hours and continue into the late evening. Greatest concern will be for gusty winds in and around thunderstorms. Localized MVFR/IFR reductions will be possible with storms. As we move towards daybreak Saturday, conditions will begin to improve with gradually clearing skies and precip moving out of the region. McKaughan && .FIRE WEATHER...Expecting scattered thunderstorms to develop through the afternoon and continue into the overnight hours. Red Flag Warnings remain in effect for all of eastern Idaho until 10PM. Gusty outflow winds up to 50 mph will be possible with the strongest of storms. Cooler weather is expected for the weekend along with higher afternoon RHs so no fire weather concerns are anticipated. Winds do look like they will become breezy on Monday and continue into much of next week. Temperatures have been trending up the last few forecasts so now looks like afternoon RHs may hover near critical levels in spots so will have to monitor for potential Red Flag concerns as we get a bit closer in time. McKaughan && .AIR STAGNATION...All air quality alerts have been lifted across the area due to improved air quality conditions. The HRRR smoke model shows improved air quality today with precipitation and southerly flow.The model then shows slightly degraded air quality in westerly flow early Saturday. However, when the upper flow aloft becomes northwesterly by Saturday afternoon the model shows improved air quality. That said, the northwesterly flow doesn`t look to last long. Models show westerly to southwesterly flow by Sunday afternoon which will bring back smoke from California by Sunday evening into Monday. Wyatt && .PIH WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 10 PM MDT this evening for IDZ410-411-413- 422-425-427-475-476. && $$
National Weather Service Raleigh NC
824 PM EDT Fri Sep 10 2021 .SYNOPSIS... Surface high pressure will dominate the weather pattern well into next week. The next chance of precipitation does not come until Wednesday. && .NEAR TERM /THROUGH TONIGHT/... As of 824 PM Friday... Quiet weather in store for the rest of tonight with sfc high pressure and dry airmass over the region. The weak upper trough currently crossing the mountains will move east tonight with no impact on our sensible weather, other than perhaps a few passing high clouds. Current sfc dwpts in the mid-upr 50s may fall a few more degrees, thus allowing overnight lows to drop to the mid 50s, with perhaps lower 50s in a few of the usual cooler locations. && .SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/... As of 240 PM Friday... While the center of the surface high will move offshore Saturday, the Carolinas will still be dominated by the influence of the high. Return flow on the west side of the high will shift winds from northerly today to southerly tomorrow, which will help bring some warmer air into the region. Most locations will have high temperatures about 3-5 degrees warmer than today, still a couple degrees below normal for this time of year. The southerly flow will also increase the nighttime temperatures about 5 degrees. && .LONG TERM /SUNDAY THROUGH FRIDAY/... As of 218 PM Friday... Not a whole lot of changes to speak of for the long term outlook over central NC. Surface high pressure located offshore of NC on Sun will drift over the central Atlantic through midweek, while lee troughing takes place over the western portion of NC. This will continue to result in rising temperatures each day with rising low- level thicknesses and increasing south-southwesterly flow. In the mid and upper levels, largely zonal flow will be in place after a mid-level trough on Sunday shifts offshore. The pattern continues to favor dry weather Sun-Tue. Highs will rise from the upper 80s to around 90 Sun to low and mid 90s come Tue. Although of little consequence, wildfire smoke seen on satellite today over the Great Plains may drift into central NC Sun and early Mon per the latest HRRR and Canadian smoke models. This could result in a little haze. Wed-Fri: Come Wed, with some return flow off the western Atlantic and precipitable water values rising slightly above average to ~ 1.3 inches in the latest GFS model, isolated storms will be possible with the lee trough and sea-breeze. Low-level thicknesses will be near or slightly below that from Tue so temperatures should still hover in the low 90s for highs. More uncertainty in the forecast takes place late in the week. In the upper-levels, the Euro/GFS show a jet streak tracking across the Great Lakes and northeast U.S. late Wed and Thu, while NC remains in more of a west-southwest flow. In the mid-levels, the Euro/GFS both indicate a trough of low pressure that circulates around AL/GA into early Sat, although the Euro shows a stronger closed low than a disorganized system in the GFS. This results in differences in large-scale lift and moisture advection into the area. Despite these differences, a more east-northeasterly flow at the surface is evident in both solutions, as well as lowering thicknesses. The GFS is a little stronger in the northerly flow from the Mid-Atlantic with its surface high off New England and a possible low pressure offshore of NC. Given the uncertainty, highs slowly trend toward climatology by Fri. As for precipitation chances, the GEFS/NAEFS ensembles favor highest rain chances in the Thu-Fri time frame. This seems reasonable given overall pattern of increasing moisture and the mid-level trough to our west. The latest forecast trended in this direction for late week. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... As of 730 PM Friday... Through 00Z Sunday: VFR conditions expected through the 24 hour TAF period with scattered high clouds and a few shallow cu during the daytime Saturday. Light winds overnight will become SSW 10kt or less during the daytime Saturday. After 00Z Sunday: VFR conditions are expected through the period with surface high pressure in place. The next chance for precipitation won`t arrive until Wednesday. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Green NEAR SHORT TERM...Green LONG TERM...Kren/JJT
Area Forecast Discussion
National Weather Service San Diego CA
142 PM PDT Fri Sep 10 2021 .SYNOPSIS... An area of high pressure over the Southwest will keep our region warm through early next week. We will see one last day of scattered monsoon storms across the mountains today before dry weather comes back into the picture. Night and morning low clouds will be quite patchy for much of the next week. The forecast looks to be a bit cooler Tuesday onward as the ridge of high pressure weakens. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .Near Term (Today through Sunday)... Bubbling cumulus and cumulonimbus clouds out our window paint the story of today`s tale. Moderate southerly flow from Mexico is contributing to an unstable atmosphere across SoCal. A moist vertical profile is seen off the Yuma, Arizona sounding from later this morning as well. Storms will continue to pop up through the afternoon and diminish by early evening, per latest HRRR and WRF guidance. The most widespread activity is expected to be across the Riverside and San Diego County Mountains. Storms may produce heavy rainfall, gusty winds, and localized flash flooding. After today`s fun filled monsoon adventure, we`ll go back to that same old same old dry weather pattern. As the area of high pressure expands westward, we`ll see warm weather continue for most inland areas with temperatures near 100 degrees from the Inland Empire and valleys of San Diego County this weekend. Coastal areas will also be quite warm with 70s near the beaches and 80s a couple miles inland. .Long Term (Monday and Beyond)... The heat won`t last for long, as high pressure over the region is expected to weaken per latest WPC cluster analysis. As this occurs, we`ll see cooling first start to impact areas west of the Mountains on Monday, with mountains and deserts starting to cool on Tuesday. The uncertainty comes into play by the middle of next week as a trough enters the Pacific Northwest around the Wednesday time frame. The strength and positioning of this trough will determine how low we go or if the high pressure across SoCal maintains it`s strength. Forecast for now points to a subtle cooling trend through the week. We will also be monitoring fire weather conditions as significant drying comes into the picture next week with breezy onshore winds through the mountains and deserts slopes with gusts 20-30 MPH expected each afternoon. && 102015Z...Coast/Valleys...Mainly SCT-BKN clouds at/above 12000 ft MSL with unrestricted visibilities. Stratus will be patchy and mostly restricted to near the coast tonight with bases 700-1000 ft MSL and tops to 1200 ft MSL and local vis below 3 miles over higher coastal terrain. Risk of low clouds at KSAN tonight after 10/09z is moderate-high so moderate-high confidence in timing of the low clouds as well as the heights of the bases/tops as indicated in the TAF. Mountains/Deserts...SCT clouds at/above 12000 ft MSL with ISOLD- SCT TSRA again over the mountains and high desert 20Z today through 02Z Sat. CB bases will be near 9000 feet MSL with tops to 40000 feet, along with strong up/downdrafts and locally gusty surface winds. && .MARINE... No hazardous marine weather conditions are expected through Tuesday. && .BEACHES... A couple of long-period south swells will move through the coastal waters early next week. The first swell of 2 feet with a period of 18-20 seconds will arrive Sunday and bring some increase in the surf, mainly to around 3-5 feet in Orange County. The second swell of 3-4 feet with a period of 16-18 seconds will arrive Monday and continue Tuesday before diminishing Wednesday. This will produce elevated to locally high surf, especially in far northern San Diego County and Orange County where highest surf will be 6-8 feet, with 3-6 feet generally occurring over San Diego from about Carlsbad south. Strong rip currents are likely at all beaches Sunday- Tuesday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...Heat Advisory until 9 PM PDT Sunday for Riverside County Mountains-San Bernardino County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Mountains-San Diego County Valleys-Santa Ana Mountains and Foothills. PZ...NONE. && $$ PUBLIC...APR AVIATION/MARINE/BEACHES...Small
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
520 PM MDT Fri Sep 10 2021 .DISCUSSION...(This Evening Through Friday) Issued at 118 PM MDT Fri Sep 10 2021 Water vapor shows upper ridge axis over the Northern Rockies/Northern Plains, with upper trof over the Pac NW. At the surface, weak trof is over the western Dakotas with cold front pushing south across MT. Hot and dry conditions continue across the region early this afternoon with plenty of smoke filling the air from western wildfires. Dry cold front will drop through the area tonight through Saturday morning, with upper trof shifting slowly into the Northern Rockies. Warm temps expected Saturday, with some 90s possible south/southeast of the Black Hills given slightly later arrival of cold front. HRRR smoke model does indicate some relief from the smoke, at least for a portion of the day. Could see a few late day storms, especially in the Black Hills and areas to the south/southeast, with better chance Saturday night further east on the plains as upper trof crosses the Dakotas. Temps will cool a bit further on Sunday, with return flow aiding in narrow axis of instability extending into northeast WY and far western SD. Should be a little better shear available as a wave moves through the zonal flow aloft, with a strong to severe storm or two possible. Upper trof slowly works through the Northern Plains Monday into Tuesday, with a continued slow cooling trend and periodic chances for showers/storms in the unsettled flow aloft. Generally warmer/drier conditions expected mid week, with somewhat unsettled conditions developing very late in the week as large trof develops over the northwestern CONUS. && .AVIATION...(For the 00Z TAFS Through 00Z Saturday Evening) Issued At 509 PM MDT Fri Sep 10 2021 VFR conditions are generally expected across the area through the period. Haze and areas of thicker smoke could produce MVFR vsbys at times in some areas, especially in northwestern South Dakota and northeast Wyoming from 00z-12z. Isolated shower and thunderstorm activity is possible over the region late tonight into tomorrow, LCL MVFR conditions are expected near any storms. && .FIRE WEATHER... Issued at 118 PM MDT Fri Sep 10 2021 The smoke filled skies have again limited mixing today, and have yet to allow winds to increase much across northeast WY. There remains some potential for a period of Red Flag conditions to develop in that area as a cold front approaches and winds pick up a little later this afternoon, so will keep the Red Flag Warning in place. Cold front will slowly spread across the region tonight and early Saturday, resulting in winds turning more northerly and slightly higher relative humidity building in. There is a very small chance for a storm or two to develop late Saturday afternoon around the Black Hills and areas to the south/southeast, with a slightly better chance Saturday night further southeast/east of the Black Hills. Unsettled and cooler conditions then expected through early next week. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...Red Flag Warning until 8 PM MDT this evening for WYZ314>318. && $$ DISCUSSION...Johnson AVIATION...Wong FIRE WEATHER...Johnson