Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/25/21


Area Forecast Discussion
National Weather Service Des Moines IA
642 PM CDT Fri Sep 24 2021 ...Aviation Update... .DISCUSSION.../Tonight through Friday/ Issued at 215 PM CDT Fri Sep 24 2021 Key Points - Showers and gusty winds through the rest of the afternoon associated with cold front currently moving through. - Well above normal temps next week possibly pushing daily records. See climate section for forecast/record info. A cold front is sweeping across the state this afternoon bringing gusty northwest winds, some showers, and cooler temps. Highest northwesterly wind gusts are occurring immediately behind the frontal boundary where the strongest caa and pressure rises reside. An hour or so of 30+ kt gusts have been common before subsiding a bit. Radar returns show scattered to widespread showers also moving through as kinematic ascent associated with a shortwave aloft overspreads the frontal zone. Precip trends and wind gusts have been a chase for much of the day as hi-res models have struggled to handle the sub-cloud dry layer. A fair share of the rain on radar has not made it to the ground today. RAP mesoanalysis has also shown little to no MUCAPE through the day, however the bubbly appearance of clouds on visible satellite and some detected lightning strikes suggests instability may be a bit more robust than models believe. Thus included mention of thunder in the forecast through the rest of the afternoon, mainly over the southern half of the area. A large area of synoptic subsidence is evident on satellite moving across the Dakotas into Minnesota. This will slide over the forecast area tonight in concert with a surface high dropping through the region. Expect another night of cool temperatures as wind relax under clearing skies, providing ideal conditions for efficient radiational cooling. Some lows in the mid to upper 30s may occur again in parts of western and northern Iowa. Forecast was trended toward a blend of MAV guidance and 25th percentile of the NBM to bring lows a few degrees cooler than previous forecast. Temperatures warm through the weekend as an upper ridge builds over the high Plains. High confidence in above average temperatures through at least the first half of next week as the upper pattern stalls a bit, leaving 850mb temps near or above 20C which is above the 95th percentile of NAEFS climo for this time of year. Monday and Tuesday appear to be the warmest days at this time and may make a run toward daily record highs, possibly exceeding 90 degrees in some areas. Upper ridge axis kicks east toward the middle to latter half of the week as mean troughing is established out west. Models suggest this will eventually transition into a closed low over the desert southwest with southwesterly flow extending into the central conus. Lift and broad waa associated with weak waves passing through the mean flow will bring precip chances back to the region. Highest PoPs are focused over western Iowa which will be near the vicinity of an inverted surface trough stretched sw-ne over the Plains. Still quite a bit of uncertainty though considering the probable rain resides in the Day 6-7 range and the potential for stubborn dry air to eat into the easterly progression of any rainfall. && .AVIATION.../For the 00Z TAFS through 00Z Saturday evening/ Issued at 638 PM CDT Fri Sep 24 2021 With gusty NW winds and scattered showers easing behind the frontal passage earlier today, VFR conditions are expected to prevail throughout this TAF period. Winds will settle westerly overnight and may gust to around 20kts at times. && .CLIMATE... Issued at 130 PM CDT Fri Sep 24 2021 Forecast record highs for early next week.... Monday Tuesday Wednesday Des Moines Forecast: 89 Forecast: 91 Forecast: 87 Record: 91 (1956) Record: 99 (1953) Record: 90 (2002) ................................................................... Waterloo Forecast: 87 Forecast: 88 Forecast: 87 Record: 89 (1954) Record: 91 (1953) Record: 90 (1953) && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Martin AVIATION...Curtis CLIMATE...Martin
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
654 PM CDT Fri Sep 24 2021 .AVIATION... Surface high pressure will continue to move east over the next 24 hours, resulting in a change in wind direction to east-southeast, and the resumption of more humid Gulf air into the area. CAVU expected tonight, with maybe a FEW015 around sunrise. Winds will be light and variable overnight, then pick around 7-9KT after 15Z. KDRT will have a slightly higher mean wind and gusty at 10G20KT Saturday afternoon. && .PREV DISCUSSION... /ISSUED 252 PM CDT Fri Sep 24 2021/ SHORT TERM (Tonight through Saturday Night)... As we wrap up another week we`ll take all the thank-you`s we can get from the south-central Texans enjoying this absolutely beautiful weather! RAP analysis depicts weak ridging aloft overhead today while surface high pressure is centered well off to our east across the SE CONUS. This ridging is progged to gradually strengthen through the short term. Weak southeasterly surface flow will continue with winds below 10mph today except across portions of the Edwards Plateau. There, RH will fall into the upper teens and lower 20s this afternoon, and briefly elevated fire weather conditions may result. Tomorrow will be a repeat performance in this area, mainly west of a line from Rocksprings to Eagle Pass. Otherwise, quiet and mostly clear today through tomorrow with moderate diurnal swings in temperature as gulf moisture is mostly held at bay for another couple of days. Lows will be mainly in the mid 50s to mid 60s the next two mornings while daytime highs today and tomorrow top out in the mid 80s to low 90s. LONG TERM (Sunday through Friday)... An upper low is expected to be located over the northern Baja peninsula on Sunday. In advance of this low, a tap of mid and upper level Pacific moisture will begin working in from the west. We will see some moisture from the Gulf begin to move back into the region on Sunday. However, the moisture will initially be shallow and we should manage to see efficient mixing and lowering of afternoon dewpoints into the 50s across all areas, except the coastal plains. Gulf moisture return really begins to ramp-up Sunday night into Monday morning with dewpoints back to feeling more like summer. The above mentioned upper low will gradually move eastward and some subtle lift could gin up a few afternoon showers and storms along and east of I-35/I-37 and across far western Val Verde county. As the upper low begins to open and eject northeastward on Tuesday, a subtropical jet on the southern edge of this low will begin to move in from the west. There is some disagreement on the location of this jet, but our region is expected to remain in the favored left exit region of the upper jet. In addition, the increase in mid-level shortwave activity and plenty of moisture, should yield scattered showers and storms on Tuesday and Wednesday. Current model data continues to show the possibility of some locally heavy rain possible late Tuesday into early Wednesday as the upper jet axis moves overhead. It will be difficult to pinpoint where this will occur, but given the stronger lift to our northwest, this would tend to favor areas along and west of the I-35 corridor. The active pattern looks to remain intact as we head into the latter portion of the upcoming work week. The medium range models show another deep upper system moving into the northern Baja/desert southwest while the subtropical high remains over the western Gulf of Mexico. This will keep our region in weak southwest flow aloft resulting in daily rain chances continuing for Thursday and Friday. High temperatures through the forecast period should remain at or just above normal with overnight lows a good 3 to 5 degrees above normal. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 61 89 62 90 67 / 0 0 0 0 0 Austin Bergstrom Intl Airport 58 89 59 90 66 / 0 0 0 0 0 New Braunfels Muni Airport 59 90 60 91 67 / 0 0 0 0 0 Burnet Muni Airport 59 87 60 88 66 / 0 0 0 0 0 Del Rio Intl Airport 63 90 64 91 68 / 0 0 0 0 0 Georgetown Muni Airport 59 90 60 90 65 / 0 0 0 0 0 Hondo Muni Airport 60 89 60 91 67 / 0 0 0 0 0 San Marcos Muni Airport 59 90 59 90 66 / 0 0 0 0 0 La Grange - Fayette Regional 59 90 61 91 69 / 0 0 0 0 0 San Antonio Intl Airport 62 88 62 89 69 / 0 0 0 0 0 Stinson Muni Airport 62 91 63 92 70 / 0 0 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Short-Term/Aviation...Zeitler Long-Term...09
Area Forecast Discussion
National Weather Service Gray ME
952 PM EDT Fri Sep 24 2021 .SYNOPSIS... Slow moving cold front will produce some heavy rainfall and embedded thunderstorms tonight into Saturday morning. Another round of heavy showers Sunday afternoon, especially over the mid-coast ans central Maine. More seasonal temperatures and the threat of showers in the mountains are expected for Monday and Tuesday, && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Update... Showers will continue to slowly exit to the east late this evening in good agreement with the latest HRRR. Radar derived rainfall rates have come down somewhat since earlier this evening. Will continue to monitor the Midcoast for a band of potentially locally heavy rain entering the region from Cape Cod and the Gulf of Maine as this area will continue to have deep moisture and high precipitable water values. Made minor adjustments to temperatures, dew points and winds this hour as drier air continues to pour in from the west. Will add more fog over New Hampshire where visibilities are lowered. Prev Disc... Cold front is progressing through the area. To the west, across NH the clearing skies are approaching. Meanwhile through Maine southerly flow will continue with showers. Low level instability remains, and some weak rotation has been observed in the convective line. Some reports of up to 2 inches of rain within the convective line. Expect the front to continue to cross the region overnight. Overall the coverage of showers has been decreasing through the day but the HRRR continues to suggest that some re development. through the mountains is possible over the next few hours. This is supported by the mesoanalysis which shows the higher shear and CAPE holding on through this area, thus have kept the thunder in the forecast through the northern part of the area through midnight. Tonight the western portion of the CWA should clear out enough for valley fog formation, and have added this to the forecast. Meanwhile across the eastern portion of the area, the front will stall keeping the scattered showers in place across the eastern portion of the area. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/... For Sunday, expect additional rainfall, especially over the eastern portion of the CWA. There are two separate features impacting the amount of rainfall. First, a weak wave rotating around the main low pressure aloft will push into the region. The more negative tilt this can archive the greater the precipitation. Secondly, low pressure along the eastern seaboard will move northwards on Sunday, pushing additional moisture into the stalled frontal boundary. These two factors will combine to lead to widespread rainfall across especially eastern Maine. With two feature competing the confidence in the placement and precip maxima still remains fairly low. Have kept total QPF fairly conservative, although certainly the upslope flow does give a potential for higher totals. This time the center of the rain will be on the upper Kennebec basin, which has been plagued by drought. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Warm ridging at 500 MB will be replace by cooler and more seasonable troughing over the NE CONUS next week, as double omega block settles across NOAM and the Atlantic, with central trough right overhead. This low will holds in place thru at least the middle of next week, when models diverge on solutions. Starting Sunday sun night should see any showers associated with the slow moving front exiting to the NE in the evening. This will be followed by clearing in the south, but clouds linger in the N as the closed upper low wobbles around over N Quebec. Lows Sunday night will be in the low-mid 40s in the mtns, to the low 50s in the S. Mon-Tue will be similar, as 500 MB closed low hangs out to the N, a and waves of energy move around that low. This will produce some rounds of clouds, and the chance of showers, mainly in the mtns. Highs will be in the low-mid 60s in the N to around 70 in the S, which is still on the high side of normal, and overnight lows 40-45 in the mtns to the low 50s in the S. Skies will vary from partly to mostly cloudy through the period with more clouds in the mtns. Confidence drops off a bit Wed-Fri, with models suggesting that another closed low breaks off on the one to out n and heads equatorward toward the SE CONUS, with some ridging developing between the two systems as the pull away from each other. Currently this would call for a mainly dry and seasonable period, but, again confidence remains low for mid-late next week. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... Short Term...Cold front is moving through the area, with MVFR ceilings currently across NH and VFR and clearing to the west. This clearing line will move eastwards overnight. Across Maine pockets of IFR and widespread MVFR will continue until he front clears the area late. Valley fog may bring IFR to the west in the morning on Saturday before conditions improve to VFR for the day. Long Term...Any flight restrictions early Sunday evening, should clear out overnight, except for lingering MVFR cigs at KHIE. Will be mainly VFR Monday through Wed, but again could see some periods of MVFR cigs at KHIE as flow from the NW persists. && .MARINE... Short Term...Gusty southerly flow and 5ft seas will keep a SCA in place across the region through evening. By tomorrow morning, winds and seas will subside and conditions will remain below SCA through the weekend. Long Term...Winds/seas expected to stay below SCA criteria Mon- Wed. && .HYDROLOGY... Heavy rain showers will continue through this evening with the potential threat for flooding along the Midcoast region of Maine. The threat for flooding does increase on Sunday through the upper Andro and Upper Kennebec basins where the focus of the heaviest rainfall exists. 6hr RFC guidance suggests that 2-3 inches in 6 hrs would be enough to push the rivers to flood stage but suspect the Sunday rainfall will be over a longer period than that. Thus while flooding cannot be ruled out feel the most likely scenario is a beneficial rain to the northern portion of the area. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 8 AM EDT Saturday for ANZ150>154. && $$ Cannon
Area Forecast Discussion
National Weather Service Marquette MI
809 PM EDT Fri Sep 24 2021 .SHORT TERM...(This evening through Saturday) Issued at 312 PM EDT FRI SEP 24 2021 GOES Imagery and RAP analysis show well a downstream upper level low that`s continued to lift northward toward James Bay through the day. Behind this and present over much of the UP for most of the day so far, has been weak ridging. This has allow for mostly clear skies and highs to climb into the 60s and 70s. Upstream, an upper level low dipping southeast through Saskatchewan is pulling a shortwave through Minnesota. At the surface, a cold has moved into western Lake Superior and cloud cover out ahead has moved into the western UP. As the upper level low/trough takes on a negative tilt, it will continue pulling this cold front from west to east through the region this afternoon and tonight. In response to increasing upper level divergence, surface cyclogensis is expected along the boundary near the WI/MI stateline. The results will be increasing low-mid level fgen that`ll result in a half inch to an inch of rain over the central UP. Elsewhere, amounts near a quarter to half inch are expected tonight. Expect skies to clear out soon after the front. This should allow lows to dip to near 40 in the west. In the east where the front will be a little slower to exit, expect lows to drop into the 40s east; the Lake Superior will help moderate temps by the northern lakeshores, so lows should bottom out near 50F. Behind the cold front, CAA will bring 850mb temps down to ~1 to 3C over the region. This, coincident with the warm lake and another trough rotating around the upper level low will support additional shower activity Saturday downwind of Lake Superior. Additionally, the steeper lapse rates that develop in response to the CAA will allow for some breezier winds near 25 mph, especially near Lake Superior and Keweenaw. There some 30 mph gusts could be possible. Daytime highs should climb into the upper 50s to near 60. .LONG TERM...(Saturday night through Friday) Issued at 321 PM EDT FRI SEP 24 2021 Saturday night, a closed upper low will be centered between Lake Superior and James Bay. A secondary vort lobe rotating around the ULL will drop southeastward across the U.P. overnight and kick off a few showers, especially over the Keweenaw and eastern U.P. A warming trend will begin on Sunday, but there could be another round of scattered showers Sunday morning with low- to mid-level Q-vector convergence overspreading the area associated with the WAA aloft. As for temps on Sunday, they will depend on the wind direction which in turns depends on whether or not a weak surface trough associated with the ULL to the north reaches the area. If it makes it this far south, then a cooler northerly wind with onshore flow from Lake Superior will develop in the afternoon and keep highs down in the low 60s, as in the NAM. If that trough washes out before it reaches the area and the flow remains westerly, then highs would make it into the mid to upper 60s. Opted to not go too far either direction and keep highs mostly in the mid 60s with this forecast, warmer near the Wisconsin state line and cooler east. Highs will be similar on Monday as skies clear with the approach of high pressure from the northwest. After Monday, the story still looks like it will be the anomalously strong ridge building over the Northern Plains and then shifting eastward into the Great Lakes. Ensemble clusters show only minor differences in the speed/placement of the ridge and virtually no variability in its strength. By Wednesday and Thursday, the lion`s share of the 00z EPS members` 850 mb temps are in the 15-19 C range which puts the EPS mean between the 90th and 97th percentile of climatology. Comparing that to the observed highs at IMT for 9/29 (chosen because of its long period of record and it not directly influenced by the lakes) that would translate to highs between 76 (90th percentile of climo) and 83 (97th percentile). Therefore, increased high temps Wednesday and Thursday into the mid to upper 70s for most. Would not be at all surprised to see some areas get back into the low 80s this week given the projected strength of the ridge. That warmth looks to continue right through Friday. By Saturday, there is an indication that a short wave rippling through the flow will begin to knock the ridge down and lead to a slight cooling trend. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 738 PM EDT FRI SEP 24 2021 A cold front is moving through the region early this evening. The front has already cleared KIWD and KCMX and the steady rain has cleared KIWD. Rain will progress west to east and could reduce visibilities at KCMX and KSAW this evening. Expect ceilings to decrease to MVFR at KCMX and KSAW with the heavier rain behind the frontal passage and then improve to VFR overnight. Northwest winds are also expected to increase behind the front, especially at KCMX where gusts could approach 30kts. Expect west-northwest winds to diminish overnight and then become gusty again on Saturday. Some isolated to scattered lake effect showers will linger over northern sections of the U.P. on Saturday and could impact KCMX at times. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 312 PM EDT FRI SEP 24 2021 Cold front will move through Lake Superior from west to east this afternoon through tonight. Ahead of the front, southerly winds near 20 kts are expected. As the system moves through, an area of low pressure is expected to develop along the boundary and lift northeast. On the backside of this system, northwest winds are expected to increase in response to the developing surface cyclone. I maintained the gale warning over the eastern half of the lake given the likelihood of gale force gusts to 40 kts. As the parent upper level low progresses slowly eastward just north of the lake, another shortwave and shot of colder air aloft will move over the warmer lake. This will support westerly to northwesterly winds increasing Saturday across the lake to 20 to 30 knots by afternoon, and 30 to 35 knots with some gale force gusts possible by Saturday evening. Expecting winds to diminish Saturday night as ridging builds in. This ridge will support winds of 20 knots or less through at least the middle of next week. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Gale Warning from 2 AM to 6 AM EDT Saturday for LSZ251-267. Gale Warning from 11 PM this evening to 5 AM EDT Saturday for LSZ249-250-266. Lake Michigan... None. && $$ SHORT TERM...JP LONG TERM...RJC AVIATION...Voss MARINE...JP
Area Forecast Discussion
National Weather Service Spokane WA
221 PM PDT Fri Sep 24 2021 .SYNOPSIS... Expect warm and dry fall weather this weekend with afternoon temperatures in the 70s. Saturday will be the warmest day with more sunshine. Winds pickup out of the southwest Saturday afternoon and become gusty Sunday afternoon. Chances for rain gradually increase late Sunday into Monday with a slow moving cold front. Cooler, showery and breezy weather prevails for the much of the work week. && .DISCUSSION... Tonight through Sunday night: High pressure remains over the Inland Northwest overnight through Saturday. The remains of a weak disturbance will pass across the region with a band of high clouds tonight. This along with a light southerly low level winds will help overnight temperatures not dip as cool as the last several nights and chances of patchy valley fog look limited. Skies gradually clear Saturday morning with plenty of sunshine by the afternoon with temperatures topping out in the mid 70s to around 80. This is unseasonably warm for the end of September and the warmest day for the upcoming week and beyond. Winds pick up out of the southwest Saturday afternoon and evening as the surface pressure trough skips east of the Cascades. Anticipate local gusts around 15 mph from the Okanogan Valley to the Palouse. Under southwest flow aloft, a Pacific upper level trough approaches the region with a slow moving cold front. Will see cloud cover and moisture push east of the Cascades Saturday night through Sunday. In fact, the HRRR smoke model shows a return of elevated smoke and haze from the CA fires drifting into the southeast Washington and parts of the Idaho Panhandle. Prefrontal southwest winds will steadily increase and become gusty Sunday afternoon and evening with sustained winds of 10 to 20 mph and gusts 20 to 30 mph, especially from the lee of the Cascades across the Columbia Basin to the Palouse. It will remain dry in most areas with considerable high cloudiness for Sunday. The Cascade crest have the better chance for a light wetting rain. Temperatures will experience a slight cooling of 3-6 degrees. Precipitable waters increase above a half inch to near an inch as the cold front finally pushes into eastern Washington Sunday night with a band of light rain. The best chance for measurable rain will be from the Cascade crest to the northern mountains, mere sprinkles are likely across the Columbia Basin. /rfox Monday through Friday: A deep low off the central BC coast will send a cold front across the region late Monday into Monday night. The strength of the wave combined with a 130-140 kt upper jet paralling the front should give most locations some rain, with the Cascade crest, SE Washington, and the ID Panhandle having the best potential for wetting rains. Some of the ECMWF and GFS Ensemble members have as much as 0.50-0.75 inches with the mean around 0.25-0.50 inches. Over Central and northeast Washington there is greater uncertainty in amounts with potential rain shadowing off the Cascades especially from the Moses Lake area up into the Okanogan Valley. Cool and showery weather is expected behind the cold front on Tuesday with snow levels in the morning as low as 5500 feet in the Cascades which includes the summit of Washington Pass. High temperatures are only forecast to reach the mid 50s to mid 60s which is about 10 degrees below normal. A short wave ridge should bring drier weather on Wednesday with patchy valley fog in the morning. Another system pushes in on Thursday into Friday bringing a chance of rain to the region. Some moderation of temperatures is likely as the flow turns southwesterly, but this could be offset by cloud cover and areas of rain. JW && .AVIATION... 00Z TAFS: High pressure remains over the region through the period, giving way to light north to easterly winds overnight. A weak disturbance will bring a band of high cirrus across the region during the night and exiting Saturday morning. Any patchy fog will be very limited early Saturday morning in the valleys of northeast Washington and north Idaho. VFR conditions are expected. Winds switch to the south/southwest Saturday afternoon with local gusts 10-15kt. /rfox && .PRELIMINARY POINT TEMPS/POPS... Spokane 48 80 53 77 53 71 / 0 0 0 0 20 30 Coeur d`Alene 48 79 52 76 51 70 / 0 0 0 0 20 30 Pullman 45 79 50 75 47 71 / 0 0 0 0 10 20 Lewiston 53 87 58 83 56 77 / 0 0 0 0 10 20 Colville 41 80 45 75 44 66 / 0 0 0 0 20 50 Sandpoint 44 75 47 72 47 64 / 0 0 0 0 20 50 Kellogg 54 78 57 75 53 68 / 0 0 0 0 10 20 Moses Lake 47 82 51 78 54 71 / 0 0 0 0 10 30 Wenatchee 54 83 58 77 58 67 / 0 0 0 10 30 50 Omak 49 84 54 78 54 69 / 0 0 0 10 30 60 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion
National Weather Service Norman OK
1031 PM CDT Fri Sep 24 2021 ...New AVIATION... .SHORT TERM... (This evening through Saturday) Issued at 256 PM CDT Fri Sep 24 2021 Latest observations show the weak surface boundary has reached the Buffalo mesonet station, which is reporting light north/northwest winds. This boundary is nearly stationary with a cold front extending northeast across central Kansas. This front will progress south, and now anticipated to be somewhat stronger than previously prog`d. Guidance shows a slight dip in H850 temperatures (by 1-2 degrees), and NBM has trended downward a bit from past runs. CAMS have trended upwards with wind speeds behind the front, though this will be short-lived and over a rather narrow zone behind the boundary. Interestingly for one day out, there is a 10 degree spread for tomorrow`s highs among the deterministic models. The NAM is at the low end and winds are prog`d to be more east/southeast by tomorrow afternoon. On the other hand, the GFS is the warmest and winds are, instead, out of the south. The HRRR and RAP both suggest more of an easterly wind component (similar to the NAM), and therefore more inclined to agree with the slight reduction in temperatures. Went ahead and adjusted maxT down slightly towards CONSSHORT. Regardless, tomorrow will be a pleasant day outside with sunny skies and temperatures in the middle to upper 80s. Southern zones will rise into the low 90s. Thompson && .LONG TERM... (Saturday night through next Thursday) Issued at 300 PM CDT Fri Sep 24 2021 A tightening pressure gradient will lead to an increase in wind speeds during the day Sunday, especially across western Oklahoma. The NBM has been running too high on dewpoints the past several days, and with dry antecedent conditions, dewpoints were lowered across portions of northwest Oklahoma during the afternoon where models have been showing a punch of drier air during peak mixing. This led to an expansion of near-critical fire conditions over our previous forecast across northwest Oklahoma, with elevated conditions expected for much of the rest of western/northern Oklahoma and western north Texas. Some signal is there for high- level cirrus during the afternoon, which may inhibit mixing some (with effects on dewpoints and winds) and will need to be watched for. Otherwise, expect breezy conditions for much of the rest of the area with highs climbing into the low 90s for most. By Monday, a cutoff low will begin to approach the area from the west, eventually opening into an open wave late Tuesday. Models have come into somewhat better agreement with regards to the overall synoptic pattern through early next week, but some differences remain. The GFS/GEFS are faster and bring showers and thunderstorms into much of the area by Tuesday afternoon, while the ECM is slower and waits until Wednesday for more widespread precipitation coverage. For now left the model blend as is, with low chances on Tuesday (highest across southern Oklahoma and north Texas), and much higher chances Wednesday and Thursday. By the end of next week model spread increases as another trough digs into the southwestern US. Regardless of the details, continued western US troughing and increasing PWATs point to a continuation of precipitation chances through the end of next week. At this time wind shear looks very weak through much of next week, which will mitigate any organized severe weather concerns. As PWATs increase toward the middle and end of next week, heavy rainfall and localized flooding of poor drainage areas may become a concern. Ware && .AVIATION... (06Z TAFS) Issued at 1003 PM CDT Fri Sep 24 2021 VFR conditions are expected through Saturday. A front will shift winds from south to northeast tonight as it moves southward through Oklahoma. It will weaken through the day Saturday. && .UPPER AIR... Issued at 1200 PM CDT Fri Sep 24 2021 No upper air flights are planned at this time. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 86 56 87 61 / 0 0 0 0 Hobart OK 88 55 90 60 / 0 0 0 0 Wichita Falls TX 88 55 91 60 / 0 0 0 0 Gage OK 89 53 87 61 / 0 0 0 0 Ponca City OK 88 55 84 60 / 0 0 0 0 Durant OK 86 56 90 60 / 0 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...01 LONG TERM....08 AVIATION...09
Area Forecast Discussion
National Weather Service Paducah KY
622 PM CDT Fri Sep 24 2021 .UPDATE... Issued at 622 PM CDT Fri Sep 24 2021 Update is for the 00 UTC TAF`s. Also, in our public products, we added some isolated thunder for the late night and early Saturday morning time frame. We see near to slightly below zero elevated li`s lifting parcels from h8/h7, along with lapse rates above 6 C/KM. Also see elevated instantaneous Flash Rates in the ECMWF data, and HRRR lightning density prog data. There may not be too much to it, but cannot rule it out given the dynamic nature of the vigorous mid trop s/wv. && .SHORT TERM...(Tonight through Sunday night) Issued at 233 PM CDT Fri Sep 24 2021 Southwesterly to westerly low level flow will increase late today and tonight ahead of a cold front, driven by a mid level shortwave out of central Canada, though surface winds tonight should be generally light out of the south. The surface front is progged to enter the northwestern fringes of the PAH forecast area shortly before daybreak Sat. This feature will result in increasing cloudiness tonight, especially overnight, and a chance of measurable rainfall for parts of southern IL, southwestern IN, and northern parts of the Pennyrile region of KY, mainly between midnight and mid-morning Fri. Areas north of I-64 will have the highest PoPs (as high as likely). The wind shift to the north should be complete by around noon everywhere as skies rapidly clear from west to east. In the wake of the front, light and sometimes variable surface winds are forecast to prevail until Sun, when the pressure gradient increases again between departing high pressure and low pressure in the central Plains. This will result in a southwesterly wind 10-15 mph Sun for us, persisting Sun night, but settling down to around 5 mph. Meanwhile, the airmass modification/warmup will continue under ample daytime sunshine, albeit with a brief pause because of the cold front. Temps should rebound into the lower 80s nearly everywhere by Sun afternoon, with lows Sun night in the upper half of the 50s in general. .LONG TERM...(Monday through Friday) Issued at 233 PM CDT Fri Sep 24 2021 Ensemble modeling suggests a warm/dry long term portion of the forecast, dominated by high pressure throughout the atmospheric column. CIPS analog data still strongly paints a dry/below normal pcpn period, and even the experimental CPC output indicates this could stretch even longer, for a prolonged dry spell perhaps measured in week(s). That said, the mid week period does offer a possibility of rainfall, at least west of the Mississippi, as return flow moisture works northward from its Lower Valley. It will come down to the strength of the holding ridge just to its east, and for now, it looks to hold strong and even backbuilds again, so our accepted blended pops are minimal, and restricted to the SEMO Ozarks, but still audibly present. The dominant high pressure and succeeding days of dry weather will help temps run several degrees above seasonal norms through the period, with daily highs in the mid to upper 80s and lows in the lower 60s. && .AVIATION... Issued at 622 PM CDT Fri Sep 24 2021 A front will move through later tonight, accompanied by a band of showers and perhaps isolated thunderstorms, best chances east of the MS River and especially SE IL, SW IN and NW KY. Cigs will lower but be mostly VFR with the front. Some reduced visibilities anticipated, but confidence in precip coverage and intensity is still lower than average. Skies will clear out from NW to SE morning to midday Saturday. Winds ahead of the front will be SSW 4 to 8 kts, switching to the N/NW 5 to 10 kts morning to midday Saturday. Now through 06 UTC, quiet weather with just high clouds. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ UPDATE...08 SHORT TERM...DB LONG TERM...DH AVIATION...08
Area Forecast Discussion
National Weather Service Reno NV
128 PM PDT Fri Sep 24 2021 .SYNOPSIS... Expect warmer temperatures with a return of west winds into the weekend. Another cold front will bring increasing winds Sunday- Tuesday and much cooler temperatures by the middle of next week. Chances for light precipitation return next week, mainly in northeast California and near the Sierra. && .DISCUSSION... Warm and dry conditions for the weekend with the current easterly flow becoming light SW-W late this afternoon and evening. This will bring the return of smoke and haze to the Sierra and western Nevada Sierra Front by early this evening, based on latest HRRR Near Surface Smoke simulations. After typical afternoon breezes Saturday, a slight uptick in winds is expected Sunday afternoon, with gusts of 25-35 mph possible. This brings fire weather concerns Sunday, however, Monday will feature even stronger winds (gusts 30-45 mph possible) ahead of an approaching cold front, with continued breezy post-frontal winds Tuesday. The current frontal timing looks to be late Monday night into Tuesday morning, with a wind shift from SW-NW behind the front. Please see the fire weather section below for additional details. In addition to the fire concerns, expect typical travel and recreation impacts. The front will usher in cooler temperatures Tuesday-Wednesday, and the spread in the guidance continues to shrink. So while there remains some wiggle room, it does look like high temps about 10 degrees below normal will result. Wednesday morning will feature the coldest overnight lows and temps could easily drop below freezing in colder rural and suburban valleys. Moisture associated with the frontal boundary is limited and the front itself moves through rather quickly, so liquid totals are likely to be minimal, generally under a tenth of an inch. Best bet for measurable rain will be the northern Sierra, northeast California, and far northern Washoe County, near the Oregon border. A few spotty, very light, showers are possible elsewhere. The bulk of the forecast simulations are pointing toward a transient ridge rebuilding over the west for the end of the week, with a lot of uncertainty thereafter. Some simulations bring another system toward the west coast, while others maintain the ridge and keep the trough in the northern Pacific for the start of October. Forecast models tend to struggle with transition seasons, and this is no exception. Check back for the latest. -Dawn && .AVIATION... Winds will begin to shift from the N/NE flow to a W/SW pattern into this evening, which could bring smoke and haze into the area from wildfires ongoing in California. KTVL may have lower visibility from the Caldor fire, while KMMH could see smoke from the KNP Complex in the Sequoia National Forest. Dry conditions dominate the area during the weekend with chances for increasing W/SW winds Sunday to near 30kts ahead of an approaching trough. Potential for mountain wave turbulence to increase east of the Sierra as the trough approaches. HRICH && .FIRE WEATHER... * Fire Weather Watch has been issued for Monday afternoon and evening for gusty winds and low humidity in western Nevada, northeastern California, and the Eastern Sierra. * Low pressure moves into the Pacific Northwest on Sunday with increasing winds across the region. Wind gusts up to 25-35 mph will be possible Sunday afternoon, along with RH values down near 10%. A couple hours of critical conditions may be possible on Sunday, but no Red Flag Warning is anticipated at this time for Sunday. * By Monday, the low pressure moves into northern CA/NV, with winds aloft increasing even more, as well as tightening of surface pressure gradients. Gusts of 30-40 mph are expected for most valley locations Sunday afternoon with gusts up to 40-50 mph possible for ridges and in wind prone areas. Latest models show a dry slot moving into the region on Monday as well, which will bring humidity down to around 10-15% for areas in western Nevada and around 15-20% west of US-395 in northeastern California and the Tahoe Basin. Expect to see anywhere from 3-7 hours of critical conditions, mainly during the afternoon/early evening hours. * Gusty winds will continue Monday night into Tuesday morning as the shortwave swings through the region. The peak ridge winds look to be early Tuesday morning as the cold front moves through the region. The ridge areas will not decouple Monday night and will continue to blow through the night. Depending on the timing of the front/shortwave, we may have to adjust the timing of the watch and any subsequent Red Flag Warnings. Winds shift out of the northwest on Tuesday behind the cold front, remaining breezy through the day. -Hoon && .REV Watches/Warnings/Advisories... NV...Fire Weather Watch from Monday afternoon through Monday evening NVZ420-421-423-429-458. CA...Fire Weather Watch from Monday afternoon through Monday evening CAZ270>272-274-278. && $$ For more information from the National Weather Service visit... http://weather.gov/reno
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Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
755 PM EDT Fri Sep 24 2021 .UPDATE... Dry and stable air above 700mb (or roughly 10k feet) per the 00Z RAOB at TBW has really suppressed any convective activity north Hardee county this afternoon as the stalled frontal boundary remains stretched from approx Naples to West Palm Beach according to the latest surface analysis. RAP still shows a juicy atmosphere south of the I-4 corridor with plenty of CAPE and no CINH - hence the thunderstorms that persist across SWFL this evening. These are moving rather slow due to the meager steering flow, so expect some locally heavy rain to be possible as Lee/Charlotte/Highlands counties have already seen solid rainfall totals this week. No changes necessary to the current forecast. Have a great weekend! && .AVIATION... A few storms linger this evening near the KPGD terminal and have put a brief TEMPO in for them, as well as left VCTS in at the other southern terminals for the next few hours. Storms should then clear out for the overnight hours, with winds generally becoming light ENE. Winds increase from the E/SE and then turn onshore after 15Z Saturday, with storms returning across the southern and inland terminals generally after 20z Saturday. VFR expected, except MVFR to IFR possible in storms. && .MARINE... Stalled frontal boundary remains stretched across south FL. East to northeast winds will prevail this weekend, but generally remain below 10 knots with benign seas expected. Any rain chances should remain south of Tarpon Springs. A shortwave trough will kick the front south of the peninsula by the end of the weekend. Overall, nice boating conditions across the Eastern Gulf of Mexico though at least the middle of next week. && .Preliminary Point Temps/PoPs... TPA 75 90 75 89 / 10 20 10 10 FMY 74 90 74 91 / 40 50 30 20 GIF 73 90 71 90 / 20 20 10 10 SRQ 74 89 73 89 / 20 30 20 10 BKV 68 90 68 89 / 10 10 10 10 SPG 77 89 76 89 / 10 20 20 10 && Sea Breeze Thunderstorm Regime For Today: Sea Breeze Thunderstorm Regime For Tomorrow: For Additional Information On Sea Breeze Regimes go to the link below https://www.weather.gov/tbw/ThunderstormClimatology && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/MARINE/UPPER AIR...42/Norman AVIATION/DECISION SUPPORT...24/Hubbard