Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/07/22


Area Forecast Discussion
National Weather Service Boston/Norton MA
940 PM EST Sun Nov 6 2022 .SYNOPSIS... The unseasonably warm conditions from the weekend will continue for one final day on Monday, with potential record highs again. Light rain showers are possible later tonight into early Monday as a cool front moves in. Canadian high pressure brings seasonable temperatures for Tuesday and Wednesday. This high moves east of the region Thursday, allowing unseasonably warm temperatures to return through Saturday. The big weather news will be heavy rainfall and possible flooding from tropical moisture associated with low pressure whizzing up the east coast...possibly remnants of a tropical system. Then a strong cold front ushers in chilly and dry air for Sunday. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... 940 PM update... Axis of convective showers still back across central NY to northern VT within the low level theta-e ridge axis. Only change to the forecast was to delay the higher PoPs until after midnight per latest HRRR and 3km NAM which show weakening showers moving into western MA after 06z. This looks reasonable based on timing of the low level theta-e ridge axis moving into SNE. Previous discussion... For tonight, the cloud cover blanketing the region will continue to do so, as we await the passage of a pre-frontal trough/surface cool front now located across central NY/PA. Expect continued unseasonably mild and humid conditions under SWly winds, breezy at times but shouldn`t be as breezy as the daytime. Aformentioned front may produce a blossoming of showers as it moves through NY, but expect a generally waning coverage as showers arrive into western MA/CT (SCT shower coverage) late this evening/midnight, then moving eastward overnight/predawn into central MA/RI and offshore by early Monday morning. Have sided toward the warmer guidance vs NBM for tonight given abundant clouds and continued modest warm advection thru southerly winds, with lows in the lower to mid 60s, similar to last night. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... 330 PM Update: Monday and Monday Night: Front will have shifted offshore by mid-morning Monday. Expect rapid clearing with full sun anticipated by late morning to the afternoon. While 925 and 850 mb temps cool, full sun and westerly downsloping flow should still allow for another day of well above normal high temperatures, which could approach daily records in the 70s. See the climate section for details on Monday`s established high temperature records for our four long-term climate stations. Though it will be unseasonably warm, the difference compared to the weekend is that the dewpoints will be plunging from NW to SE, from the lower 60s to the mid 30s/lower 40s by Monday afternoon. Will still be fairly breezy with deeper mixing driven by stronger cold advection into the mid to late afternoon (continuing into the night). Westerly gusts around 25 to 30 mph, highest across the terrain. A much colder, more seasonable air mass moves into the area for Monday night, as a ridge from a strong 1040+ mb anticyclone builds in from the west-northwest. 925 to 850 mb cold advection becomes pretty stout for the evening; favoring continued mixing even though temperatures should fall fairly quickly in the evening. Didn`t go quite as cold as some of the guidance but shown lows in the mid 30s to lower 40s. NW winds could gust in the 20 to 30 mph range, highest in the Berkshires, the hills in northern Worcester County and the coastal areas. && .LONG TERM /TUESDAY THROUGH SUNDAY/... 420 PM update... Highlights... * Normal temperatures Tue/Wed and above normal Thu/Fri/Sat * Potential for heavy rain and urban flooding Friday night into Saturday... * Much colder Sunday. Details... Tuesday through Thursday... Strong high pressure moves from Ontario Tue to southern New England Wed, then off the coast on Thu. Sunny skies and clear nights are expected through Thu. Temperatures will be closer to normal Tue and Wed, with highs mainly 50 to 55, then warming to 60 to 65 Thu as winds turn southerly. Overnight lows could be chilly Tue night with 20s to lower 30s...but mainly 30s Wed night and 40s to lower 50s Thu night. Friday... Upper level flow turns southerly along the eastern seaboard, allowing tropical moisture to stream rapidly northward. Sunny skies in the morning will become cloudy in the afternoon and there is a chance of rain over western MA, northern CT, and RI late in the afternoon, way out ahead of low pressure moving up the coast. Depending on the length of sunshine, high temperatures could soar to 65 to 70 over much of the region. This could approach but just fall shy of record highs. Friday night and Saturday... Of course this is 5+ days in the future and subject to much change, but as of now, the GFS, Euro, and Canadian models all are in amazing agreement with each other. NHC gives a 90 percent chance of development of a tropical system next week that heads westward toward the southeast U.S. The remnant low pressure from this system is forecast to lift rapidly north/northeast, passing near or east of Cape Cod/Nantucket by Saturday afternoon. The moisture associated with this system will be anomalously high...with precipitable waters near 2.00 inches. Rainfall could be very heavy with 2 to 3 inches falling in a 12- to 18-hour period, mainly from before midnight Friday night to just after noon on Saturday. The heaviest rain should be from about I-95 Providence to Boston corridor, eastward to Cape Cod and the Islands. The Euro has a max of 4 inches over the Cape and Nantucket. Isolated thunderstorms are possible in southeast MA and RI, where the K Index reaches 35-37. The 0-1km helicity is 400-500 but low level CAPE is currently forecast to be confined to the southeastern coastal waters. This will need to be watched but right now any spinups should be confined to the outer waters off of Nantucket. Rain ends from west to east Sat afternoon. Depending on the track of the low pressure, strong winds are possible along the coast... with southerly gales likely over the southern and eastern coastal waters. Again...this is subject to much change between now and Friday and highly depends on the evolution of a potential tropical system over the southeast U.S. Stay tuned. Sunday... Westerly winds bring dry, but very cold air into the region. High temperatures are forecast to only reach the 40s west and lower 50s east, as 850 mb temperatures plunge to -6C to -7C. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. 0045Z update: Tonight: Moderate confidence. Marginal Low-level Wind Shear added to BOS and PVD TAFs late tonight for a few hours, as low level southwest jet of 40 kt develops. This is contingent on surface winds dropping to below 10 kt, which is possible for a short time. Previous discussion... Ceilings lower to MVFR, possible IFR from ORH westward with periods of light SHRA. Brief period MVFR ceilings possible 09-13z Mon for the eastern airports but think VFR would predominate. SW gusts should ease to sustained winds 12-15 kt with low-level wind shear still possible with less gustiness. Monday: High confidence. Sub-VFR ceilings become VFR 12-14z in the west, around 13-15z for the eastern/coastal TAFs. SW winds shifting to W then WNW later in afternoon. Gusts to 20-25 kt. Monday Night: High confidence. VFR. Breezy NW winds with surge of colder air, gusts 25-30 kt. KBOS Terminal...High confidence in TAF. KBDL Terminal...High confidence in TAF. Risk of unrestricted- visby rain showers thru 20z but runways dry. Outlook /Tuesday through Friday/... Tuesday through Tuesday Night: VFR. Breezy. Wednesday: VFR. Wednesday Night through Thursday Night: VFR. Breezy. Veterans Day: Mainly VFR, with local MVFR possible. Chance RA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Overall high confidence. 745 PM update... Boston Harbor and Narragansett Bay SCAs have been allowed to expire at 7 PM. Otherwise, SCAs continue on most waters for marginal 25 kt gusts on the eastern waters and along the southern offshore waters for rising seas into the 5 ft range. Winds still will run on the borderline SCA level into Monday, with initial SW winds tonight becoming W on Monday. While there are no headlines issued or extended into Monday night, we`ll definitely need marine headlines for that given the anticipated surge in colder air aloft and NW pressure gradient. Thinking gusts will be in the strong SCA level (30-kt gust range) Monday night, but it`s possible we could have gusts nearing Gale force on the northern waters. After coordination with neighboring offices, opted to refrain on hoisting gale watches and defer to later-coming guidance before making that determination. Outlook /Tuesday through Friday/... Tuesday: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Seas up to 5 ft. Tuesday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Wednesday: Winds less than 25 kt. Areas of seas approaching 5 ft. Wednesday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Thursday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of seas approaching 5 ft. Thursday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Veterans Day: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain. && .CLIMATE... Record Daily High Maximum Temperatures for Sunday November 6 BOS 73 in 1938, 1948, 1959 and 2015 BDL 76 in 2015 PVD 72 in 1948, 1959, 1994, 2015 and 2020 ORH 71 in 2020 Record Daily High Minimum Temperatures for Sunday November 6 BOS 62 in 2015 BDL 60 in 2015 PVD 62 in 2015 ORH 59 in 2015 Record Daily High Maximum Temperatures for Monday November 7 BOS 77 in 1938 BDL 79 in 2020 PVD 76 in 2020 ORH 75 in 1938 Record Daily High Maximum Temperatures for Friday November 11 BOS 73 in 2020 BDL 72 in 2020 PVD 74 in 2020 ORH 68 in 2020 && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 7 AM EST Monday for ANZ231>235-237- 251. Small Craft Advisory until 7 PM EST Monday for ANZ250-254>256. && $$ SYNOPSIS...Loconto/GAF NEAR TERM...KJC/Loconto SHORT TERM...Loconto LONG TERM...GAF AVIATION...Loconto/GAF MARINE...Loconto/GAF CLIMATE...
Area Forecast Discussion
National Weather Service Dodge City KS
431 PM CST Sun Nov 6 2022 ...UPDATE TO AVIATION... .SHORT TERM...(This afternoon through Monday evening) Issued at 1037 AM CST Sun Nov 6 2022 Weak west to southwesterly flow aloft with surface high pressure to the north that will slowly shift east through the afternoon and evening hours. Gusty north to northeast winds up to 20-30 mph will turn more easterly overnight with the aforementioned high pressure`s movement eastward diminishing with radiational cooling to less than 10-15mph. Sunday afternoon high temperatures into the low to mid 60s under ample sunshine with overnight lows dropping mainly in the 30s, touching the freezing mark for counties to the northwest into west central Kansas. Monday will see increasing mid level clouds during the morning time frame ahead of a shortwave that will propagate through the CWA into the evening and overnight hours into Tuesday morning. With increasing moisture with the southeast surface flow, precipitation chances look to increase into south central portions of the state and points east. The disturbance is pretty progressive that will likely leave anything west of Hwy 183 corridor dry. Patchy fog cannot be ruled out for Monday morning during the new work week`s commute but confidence low as the HRRR is the only model picking up on any development for northwestern counties with minimal visibility restrictions expected. Otherwise, expect another similar afternoon Monday temperature wise with high in the low to mid 60s once again. Not much to come in the long term with mainly dry conditions and increasing wind and fire danger to come mid week ahead of the next cold front to come late Thursday. .LONG TERM...(After midnight Monday night through Saturday) Issued at 1159 AM CST Sun Nov 6 2022 With upper level ridging building in across the Rockies and high plains due to increasing divergence aloft, leeside troughing will develop and deepen into the long term forecast Tuesday and Wednesday. South to southwest winds expected to gust over 40 mph increasing fire danger as well. Downsloping winds will aid in afternoon high temperatures to push well into the 70s both afternoons with morning low more mild into the 40s. Wednesday night will see a disturbance propagate down the aforementioned ridge that will see limited precipitation potential with northwest flow aloft, increasing into central and south central portions of the state and east to southeast from there. More ample low level moisture will be had in that direction with ample advection from the Gulf the further east for this system to feed off of. Otherwise, expect the cold front to push through Thursday morning and into the afternoon hours that will inhibit as warm temperatures fluctuation from the low 60s to low 70s depending on the timing of FROPA. Being this far out, models are not consistent on its timing. North winds can be had behind the front not seeing any strong gusts at this point. Continued cooler temperatures Friday and over next weekend with improved skies with morning lows in 20s and afternoon highs struggling to reach the 50 degree mark. In essence, the dry and drought filled conditions will continue with models showing no precipitation chances for most of the CWA, except for the minor chances for eastern counties of south central Kansas overnight Wednesday into Thursday morning. A cool and dry trend will continue through mid to late month as long term outlooks show this to be the pattern over the next couple of weeks. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 427 PM CST Sun Nov 6 2022 VFR conditions will prevail in vicinity of all TAF sites through early Monday. Light east-northeasterly winds will persist overnight as surface high pressure edges east through the Northern Plains. Winds will turn southeasterly 10 to 20kt mid/late Monday morning as the surface high pushes farther east into the Upper Midwest. && .PRELIMINARY POINT TEMPS/POPS... DDC 34 62 50 72 / 0 0 10 10 GCK 32 60 48 72 / 0 0 10 10 EHA 33 61 50 73 / 0 0 0 10 LBL 34 63 49 74 / 0 0 10 10 HYS 34 59 49 71 / 0 0 20 10 P28 39 63 53 72 / 0 0 40 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Lowe LONG TERM...Lowe AVIATION...JJohnson
AREA FORECAST DISCUSSION
National Weather Service Eureka CA
252 PM PST Sun Nov 6 2022 .SYNOPSIS...A potent cold storm system will bring snow to the mountains and rain to valleys and coastal plain tonight through Tuesday. Some thunderstorms with small hail are forecast tonight through Tuesday. Drier weather is forecast for Wednesday through Thursday, though isolated showers may linger on Wednesday. Another front will approach on Friday and may bring more rain with snow in the mountains next weekend. && .DISCUSSION...Satellite imagery and surface analysis showed another potent cold front progressing southeast along the central Oregon coast this afternoon. Southerly winds have been gusting to 45 mph over the Del Norte coastal headlands and higher terrain in advance of this surface boundary. High resolution model guidance, particularly the HRRR, has been consistently indicating a narrow wavy line of high reflectivity developing this afternoon offshore over the coastal waters and approaching the coast. 925mb S-SW winds around 40-50kt support the potential for strong wind gusts with this line of high reflectivity or squall by the late this afternoon, followed perhaps by W-SW gusts (40 mph) or more into early this evening after frontal passage. So far precipitation across the area has been on the light side with 12 hour totals around 0.10 to 0.30 in Del Norte county to a tenth of less for northern Humbodlt. The precipitation rates will increase this evening as the boundary sags southward. Locally heavy rates from 0.30 to 0.50in/hr or probably for favorably upslope regions of the Del North and Humboldt counties. Even the highest rates from the HRRR are under hourly threshold for debris flow on recent burn scars. We would hourly rates closer to 1 in/hour. These high rain rains will taper off as the front heads southeast into Mendocino and Lake counties later tonight. Satellite imagery also showed an impressive field of open cell cumulus convection trailing the cold front. Snow levels will fall later tonight, around 3000-3500 feet, after frontal passage. Higher elevations of Del Norte, northern Humboldt and Trinty counties will receive a foot or more of snow by early Monday morning. The forecast problem will lower elevations, below about 3000 feet. HRRR indicate snow levels 200 to 500 feet lower than the multi-model guidance for location between 2500-3000 feet in Del Norte and northern Humboldt counties. Advisory level snow accumulation, 2-3 inches in 12 hours will be possible especially for Collier Tunnel where multi-model guidance has a 60% probability for an 1 inch. Probabilities for an inch of snow at Berry Summit on 299 and on highway 36 around Dinsmore (2500-3000 ft) are 20-24%. Some wet heavy snow may accumulate on the roads at these lower elevations tonight. For now, we highlighted this in social media posts since there is a winter storm warning for heavy snow above 3000 feet til 3 AM. Unsettled weather conditions will continue for Monday through Tuesday as a cold upper level trough slowly digs south over the area. Snow showers will continue for the mountains, with snow levels fluctuating around between 3000 to 4000 feet. Additional snow warnings and/or advisories will likely be necessary after the first dumping of snow in the mountains tonight. With 500mb temperatures around -30C, CAPE around 200J/kg or less, steep 850mb-500mb lapse rates and low equilibrium levels, isolated thunderstorms and small hail will remain a distinct possibility especially on Monday or Monday night. SREF guidance continues to indicate low probabilities for most the southern portion of the forecast area, Mendocino and Lake counties on Tuesday. The upper level trough/cold air aloft will begin to eject into the Great Basin/Desert SW around mid week. Some showers due to the lingering cold temperatures aloft and wrap around moisture may occur on Wednesday. Ridging/warming aloft will start to build into the area Wed night and Thu for the what looks like the best opportunity to dry weather and freezing valleys temperatures and coastal frost. Forecast uncertainty increases Friday and over the weekend as another trough approaches the Northern California coast from the west. Ensemble clusters and deterministic models show considerable variability with the timing, depth and progression of the 500mb trough. We will probably see some more rain or mountain snow Friday through Monday. How much, when exactly and for how long is up in the air and error prone this far out. && .AVIATION...A strong cold front is impacting the terminals this afternoon. A line of rain and some thunderstorms is passing along the front which is creating periods of heavy rainfall and mixing down gusty southerly winds to the surface. The front will have passed CEC soon after 23Z and ACV around 0Z to 01Z. Winds at the surface have verified more SSE at ACV, thus LLWS will be present until FROPA with winds aloft SSW at 40kt at 1500 AGL. A WSHT should be expected with the FROPA. CCIGS have come down to IFR levels at times with the rainfall. General MVFR CIGS are expected to be maintain overnight with OCNL VFR while lingering isolated showers stream in. Heights should range from generally the 2000 ft to 4000 ft range, with bouts of brief lowering with the more productive showers. The front will impact UKI shortly with light to brief moderate rainfall and CIGS getting into MVFR criteria before conditions will improve after 6Z when the front passes. && .MARINE...A passing front is creating gusty southerly winds along it, especially in bands of convective showers and some thunderstorms over the waters. Up to 40 kt gusts have been recorded in portions of the northern waters. This activity will be progressing southward through the southern waters the remainder of the afternoon and into the evening. Additionally, a solid mid period swell will start to build in tonight and Monday peaking 16 to 18 feet at 15 seconds Monday evening. Current guidance remains right on the threshold of haz seas, but offshore buoys have confirmed modeled heights so current thinking is that this will remain just shy of the 18 ft seas criteria. This swell will then slowly decay into mid next week. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Winter Storm Warning until 4 AM PST Monday for CAZ102-105- 107-108. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PST Tuesday for PZZ450-470- 475. Small Craft Advisory from 9 PM this evening to 3 AM PST Tuesday for PZZ455. && $$ Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png
Area Forecast Discussion
National Weather Service Goodland KS
338 PM MST Sun Nov 6 2022 .SHORT TERM...(This evening through Tuesday Morning) Issued at 210 PM MST Sun Nov 6 2022 Zonal flow is dominating the plains currently with mid clouds streaming eastward just north of the area. At the surface a high pressure system was located over the Nebraska Panhandle where a cold front is located. For the rest of the the day clear to partly cloudy skies will persist with highs in the 50s to low 60s across the area and lighter winds. Overnight winds will slower become ESE and remain light. High clouds will move in from the SW as low temperatures fall into the upper 20s over the east and low 30s over the west. Moisture advection increases from the SE around sunrise which looks to lead to low stratus developing and perhaps some fog. The HREF, HRRR and CONSHORT are aggressive with the magnitude of the fog with dense fog developing. My confidence in fog isn`t overall the highest currently as winds are expected to be fairly breezy over the western part of the area which typically doens`t support fog, but perhaps with amount of moisture advection this can be realized. The surface high as mentioned above looks to nose its way into eastern portion of the area as well where the winds will be lighter so did nudge the patchy fog in the forecast a bit more to the east than what guidance is showing to account for this. I am also a bit skeptical on the fog formation due to the overall dry conditions which may limit the magnitude of the fog as well. Overall, patchy fog has been added into the forecast. Monday, guidance does actually show fog/stratus all day which would limit how warm it actually does get so went with a blend of ConShort/CONSMOS for highs. High temperatures are currently forecasted in the upper 40s to mid 50s across the area but may be cooler depending if the stratus does hold on all and the magnitude. The prolonged cloud cover would also limit the wind gust potential, sustained winds would still be breezy around 15-20 knots but would essentially eliminate any 30+ knot gusts where the cloud cover holds. Monday night and into Tuesday, guidance shows stratus and fog potential again developing over the eastern portion of the area which would keep low temperatures warmer int he upper 40s to low 50s with western areas a bit cooler in the upper 30s to mid 40s. .LONG TERM...(Tuesday through Sunday) Issued at 210 PM MST Sun Nov 6 2022 The extended period looks to be more active as a strong trough develops over the SW CONUS. A rather dynamic pattern looks to develop starting Tuesday. Moisture advection looks to be rather strong on Tuesday with higher dew points from the Gulf of Mexico moving into the area. Will need to keep an eye out for fog/stratus potential Tuesday morning as well but with the breezy winds expected overall confidence in being able to pin point any fog development at this time is low so will not be introducing into the forecast. Breezy to gusty winds look to develop during the day with gusts up to 40 mph at times along with high temperatures in the low to mid 70s across the area. A shower or thunderstorm can`t be ruled out over the eastern portion of the area during the late afternoon/evening hours, however due to lack of obvious forcing will leave the forecast dry. Into mid week, gusty to windy conditions look to continue across the area as the upper level trough begins to undergo cyclogenesis. The overall track of the system remains in question as the ECMWF develops the low over the Front Range and brings it to the north of the area which is a favorable track for strong winds and dry conditions. The GFS develops the low over the CWA which may lead to the development of showers and storms, if this does verify then couldnt rule out the potential for severe storms to occur due to the moisture in place and forecast soundings suggesting strong 0-6km shear. Near critical to critical fire weather conditions will need to be watch Tuesday and Wednesday across at least east Colorado as gusty to windy conditions look to develop during the afternoon and the potential for additional drying due to the southwesterly winds. RH values are currently forecasted in the upper teens; but these may change based on the track of the system. Wednesday night a strong cold front associated with the system swings through the area causing a significant change to the temperatures with temperatures falling throughout the day Thursday. High temperatures Thursday range from the low 40s to mid 60s with possibly some high temperatures being set at midnight. Cool temperatures will then continue into next weekend. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 334 PM MST Sun Nov 6 2022 Winds will slowly become ESE overnight as light winds less than 10 knots will persist. As winds become more SE moisture advection begins to move into the area along with the nose of a ridge axis into the northern portion of the area. Low Status/Fog looks to develop around 12Z with the highest potential affecting KGLD; can`t rule it out completely for KMCK at this point but confidence is lower due to the expected moisture axis. Any fog/stratus looks to dissipate mid to late morning with breezy to gusty winds developing during the afternoon at each site. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...Trigg LONG TERM...Trigg AVIATION...Trigg
Area Forecast Discussion
National Weather Service Marquette MI
525 PM EST Sun Nov 6 2022 .SHORT TERM...(Through Tonight) Issued at 300 PM EST SUN NOV 6 2022 Water vapor imagery and RAP analysis show a weakening/opening up mid- level low over southern Manitoba. Shortwave swinging around this feature is currently moving across Lake Superior/Upper MI. This wave generated some -shra this morning across portions of Upper MI. In its wake, drier air is surging into the fcst area, resulting in clearing skies, though daytime heating and caa are conspiring to generate sct to ocnl bkn stratocu from far nw WI into western Upper MI. With the appearance of the sun, temps have risen into the upper 40s to mid 50s F. Winds will be the main issue going forward into and thru tonight. Sfc low pres over se Manitoba will open up into sfc troffing across northern Ontario tonight. Tight pres gradient setting up btwn the trof and sfc high pres ridging se into the Northern Plains down to the Ohio Valley, pres rises approaching from the w (center of max rise of 8-9mb/3hr moves along the International Border from ND/Manitoba to MN/Ontario during the night), and caa (850mb temps fall to around -7C) will set the stage for a very windy night across Lake Superior and the Keweenaw. Models have shown good consistency on this setup for the last couple of days, and latest round of model runs shows no surprises. Fcst soundings indicate efficient mixing thru winds ranging btwn 40-50kt over the waters, extending across the Keweenaw. Initial sw low-level flow thru late aftn and wsw flow this evening is not the ideal direction to maximize wind potential on the Keweenaw, but winds will steadily ramp up during this time. Peak wind time across the Keweenaw will be overnight as winds veer to a more favorable 270-280 direction. It is also at this time that models show low- level wind fields reaching their max. Expect peak wind gusts across the Keweenaw to occur 06-12z when gusts could occasionally approach 60mph. The strong westerly winds across western Lake Superior will build large waves that will lead to beach erosion/beach flooding on the Lake Superior beaches/shore along the w wide of the Keweenaw. Overlake instability will be marginal for any lake effect pcpn, and given the drier subcloud look on fcst soundings, pcpn seems unlikely. However, there is pcpn currently over ne ND/nw MN. The deeper moisture supporting this activity may pass far enough s to support isold very light shra/shsn development late tonight across the Keweenaw. Elsewhere tonight, expect clear to partly cloudy skies. Winds will generally gust 20-30mph thru the night west half and 15-25mph east. Expect min temps in the mid 20s to mid 30s F, coolest interior w. .LONG TERM...(Monday through Sunday) Issued at 300 PM EST SUN NOV 6 2022 Calm, cool, and quiet weather settles across Upper MI on Monday then the next surge of warmth and moisture begins on Tuesday. A warm front stalls across the area Tuesday through Thursday night resulting in several rounds of rain and thunderstorms too. Locally heavy rainfall is increasingly likely with ensembles putting the heaviest amounts across the western UP. A late week cold front allows winter to make a comeback with snow chances returning on Friday. Some snow accumulation should be expected next weekend within the prevailing lake effect snow belts. Breezy conditions subside Monday morning as surface ridging builds east into our area. Westerly winds at 12z gradually veer northwesterly on Monday, which should allow lake effect rain or snow showers to move into our far eastern counties. Inversion heights around 3kft and a dry sub-cloud layer suggests lake effect showers will struggle to produce much QPF. However, lake effect clouds are expected to be common along the Lake Superior shoreline. Surface ridging Monday night suggests potential for cooling below NBM guidance. At this time, the best chance for calm winds and clear skies appears to be the eastern UP since mid and upper level clouds and light southerly flow should be developing across the western UP. The upper level pattern amplifies on Tuesday resulting in increasing southerly winds, especially Tuesday night when a low level jet moves overhead. The LLJ transports rich Gulf of Mexico moisture into our area spelling the beginning of another rain storm. This LLJ precedes an inverted trough tracking across Ontario toward James Bay on Wednesday. Continued warm air advection and associated isentropic ascent should lead to shower and perhaps thunderstorm development late Tuesday night through Wednesday. As the inverted trough lifts northeast, it`s trailing cold front stalls and provides the baroclinic breeding grounds for a powerful storm system expected to impact most of the Midwest Wednesday night through at least Friday. By midnight Thursday morning, pressure falls are expected across northeastern CO with deep SW flow aimed at the UP. Ensemble surface low tracks suggest the low occludes near the SD/ND/MN tri-state before slowly moving east on Friday. The southern shoreline of western Lake Superior appears to be a favored baroclinic zone for this system leaving our CWA in the warm sector. Pwat values exceeding 1" are likely across the UP and there`s good model agreement for enough MUCAPE to justify including thunderstorms in the forecast. Model soundings show an LLJ warm nose indicating any thunderstorm activity will be elevated. Deep layer flow approximately parallel to the warm front suggests potential for training storms that will be capable of producing locally heavy rainfall. While severe storms are not expected, strong thunderstorms appear plausible given adequate deep-layer shear, some veering with height, and CAPE approaching 1000 J/kg. The primary hazard with any strong thunderstorms is small hail and heavy rain rates. A much colder air mass fills in behind this low pressure system, allowing wrap-around precipitation to transition from rain to snow. With 850 mb temperatures cooling below -10C snowflakes should be observed down to the lakeshores, but accumulation potential remains unclear. Model soundings show the lake-induced inversion extending into the DGZ so there`s some potential for fluffier snowfall. Below normal temperatures and lake effect snow chances appear likely to persist through the weekend and into next week. Winter is coming!!! && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 525 PM EST SUN NOV 6 2022 VFR will continue at IWD/SAW thru this fcst period. At CMX, increasingly colder air flowing across the relatively warm waters of Lake Superior will result in cigs slipping to high MVFR at CMX late tonight into Mon afternoon. Winds will be a factor. Expect sw winds to increase during the aftn with gusts reaching 25-30kt at IWD/SAW and 30-35kt at CMX. Tonight, gusts at SAW will be around 25kt, at IWD 30-35kt and at CMX around 45kt. Winds will begin to diminish Mon morning. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 253 PM EST SUN NOV 6 2022 Winds are already ramping up across western Lake Superior this afternoon and are expected to continue increasing this evening and overnight. Strong cold air advection and pressure rises support high end southwesterly gales across the western lake this evening that veer westerly while spreading eastward across Lake Superior. Some storm force gusts should be expected, particularly after midnight across south-central portions of the lake near the Keweenaw. Winds subside from west to east on Monday and look to be below 20kts lake-wide by Monday evening. The calmer conditions persist into Tuesday, but southeast winds increase to around 25kts across eastern Lake Superior by Tuesday evening when an LLJ moves overhead. Southerly winds decrease below 20 knots from west to east on Wednesday, but a low developing on the Central Plains appears likely to bring another round of northeasterly gales -if not storms- late Thursday into Friday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Lakeshore Flood Advisory until 9 AM EST Monday for MIZ001-003. Wind Advisory until 9 AM EST Monday for MIZ001-003. Lake Superior... Gale Warning until 9 AM EST Monday for LSZ162-240>242-263. Gale Warning until 10 AM EST Monday for LSZ243-244-264. Gale Warning until 11 AM EST Monday for LSZ245>251-265>267. Lake Michigan... Gale Warning from 9 PM this evening to 7 AM EST Monday for LMZ221-248-250. && $$ SHORT TERM...Voss LONG TERM...EK AVIATION...07 MARINE...EK
Area Forecast Discussion
National Weather Service Nashville TN
530 PM CST Sun Nov 6 2022 ...New AVIATION... .SHORT TERM... (This afternoon through Monday Night) Issued at 138 PM CST Sun Nov 6 2022 Satellite imagery this afternoon shows clouds spreading back northward across the area, with radar indicating an area of light rain moving northeastward through the midstate. Have adjusted pop through this evening based on the latest HRRR model, but most areas should be precip-free by early this evening. Late this evening and overnight, 12Z models and CAMs all show more widespread showers breaking out throughout the area, which will then shift slowly southward into Monday morning as the stalled frontal boundary gets a nudge. Precip chances have been raised significantly for tonight with chance to likely pops, and additional rainfall amounts up to one quarter inch are possible. In addition to the showers, ample low level moisture, light winds, and the stalled front should all combine to produce widespread fog tonight - and it could be dense in some areas. Area will dry out by Monday afternoon with highs warming up well into the 70s once again. && .LONG TERM... (Tuesday through next Sunday) Issued at 138 PM CST Sun Nov 6 2022 Tuesday through Thursday looks dry and quite warm with highs in the 70s and 40s/50s thanks to a strong upper level ridge building overhead. These temperatures are around 10 to 20 degrees above normal for this time of year. 12Z models continue to show a tropical cyclone developing off the east Florida coast that moves westward across the state later this week, and moisture wrapping around the northern side of the system could bring some showers to our eastern counties on Friday. Late Friday into Friday night, a strong cold front will sweep through the region bringing gusty northwest winds and a much colder and drier airmass into the midstate, with lows dropping into the 30s Saturday morning and 20s Sunday morning. After a week of much above normal temperatures, looks like we will have to pay the piper with much below average temps for next weekend into the early part of the following week. && .AVIATION... (00Z TAFS) Issued at 524 PM CST Sun Nov 6 2022 Stationary boundary to remain draped across the mid state through tonight. Low level moisture will be in place and with some added isentropic upglide, periods of shower activity are expected overnight and into Monday. Dewpoints are notably lower across far northern middle TN, but the soupier dewpoints should prevail through the taf period for the taf areas. Some advection fog may occur so look for some vsby reductions toward and through 12Z especially. Otw, cigs will also chime in and be within the IFR range as well. && .PRELIMINARY POINT TEMPS/POPS... Nashville 63 75 55 76 / 60 30 0 0 Clarksville 58 73 51 73 / 40 10 0 0 Crossville 59 71 50 72 / 50 40 0 0 Columbia 63 76 54 77 / 50 30 0 0 Cookeville 63 73 53 74 / 60 40 0 0 Jamestown 60 70 48 70 / 60 40 0 0 Lawrenceburg 62 77 55 77 / 40 30 0 0 Murfreesboro 63 76 54 77 / 60 30 0 0 Waverly 60 73 52 74 / 50 30 0 0 && .OHX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Shamburger LONG TERM....Shamburger AVIATION.....21
Area Forecast Discussion
National Weather Service Pendleton OR
719 PM PST Sun Nov 6 2022 .UPDATE...Center of the closed low is currently off the coast of NW Washington and slowly moving southward. This has a slow moving cold front stretching from SW Oregon up into eastern Washington at this time. Area radars show a band of precipitation along the front. This has been mainly impacting the western portion of the forecast area through the evening with some rain and snow. Snow levels have ranged from around 2500 feet in the central and southern WA Cascades to around 4000 feet in central Oregon. These snow levels will lower another 1000 feet overnight with precipitation changing over to showers. The front will move into the eastern portion of the forecast area overnight spreading precipitation into that region and then exit into Idaho Monday morning. Eastern mountain snow levels will begin falling overnight reaching 2000 to 3000 feet Monday morning allowing for some light accumulations. Made some adjustments to increase POPs and QPF, increase southerly winds over the eastern mountains and raise overnight lows across the eastern portion of the forecast area. .SHORT TERM...Sunday through Tuesday...A broad, deepening low pressure system will orient the flow aloft more SW throughout the day today, causing the current mountain snow threat to shift more toward the OR Cascades, as well as bring a band of light precip eastward across the rest of the CWA. Latest radar imagery showing showers developing in the WA Basin, while snow starts to pick up across the OR Cascade crests. Winter Weather Advisory remains in effect across the OR Cascades through this evening. Still expecting most snowfall impacts to occur over 4000 ft at pass level and in the crests for OR, while WA has now seen the bulk of its snowfall with the main moisture transport axis shifting more southward. With the flow shifting SW ahead of the deepening low, winds have picked up across the forecast area, particularly in central OR along with the Grande Ronde Valley and downslope from the Blues. Seeing gusts up to 40 mph across these areas, but feel that impacts are isolated enough and that winds should decrease later today to preclude any headlines. The center of this deepening low will start to move overhead heading into Monday, allowing for winds to slacken as colder, drier air advects in. Latest HRRR guidance still showing a band of showers rolling through the CWA beginning around 5 PM near the foothills of the Cascades, spreading eastward into the overnight hours. Precip still looks pretty light, even in the eastern mountains, so not expecting anything too impactful for the rest of the day Sunday east of the Cascades. For the start of the work week, models show light precip chances across most of our mountain zones, shifting toward the southern mountains of our CWA heading into Tuesday as the low continues to deepen into the Great Basin, shifting its moisture advection belt more southward. QPF ensembles coming up on the light end of precip, as more favorable moisture transport falls more east and south of our area. Net effect will primarily be the beginning of a cold spell, as dry and cold northerly air seeps in with this deepening low. Highs by Tuesday will struggle to eclipse 40 degrees, even in the lower Basin, with overnight lows falling into the teens and 20s across the forecast area heading into Wednesday morning. Evans/74 .LONG TERM...Wednesday through Sunday...Very little has changed in the forecast since yesterday. Mostly dry conditions are expected through the period with the main concerns being well-below- normal temperatures across the Inland Northwest, and a slight chance of low-elevation wrap-around snow Wednesday morning. Wednesday, ensembles and current 12Z deterministic runs, are in very good, though not excellent, agreement regarding the placement of a cut-off upper-level low moving onshore into SW OR or NW CA. Ensemble cluster analysis reveals the main source of uncertainty, accounting for 40% of the variance among members, is the longitudinal placement/progression of the low. A secondary source of uncertainty, accounting for 19% of the variance, is how far the low will dig south. Much like yesterday, the ECMWF/EPS is continuing to advertise a slightly more northerly placement than the GFS/GEFS, though now the Canadian/CMC is in better agreement with the ECMWF/EPS. This solution is slightly favored by ensembles (56% of overall members) and would allow slight chances of snow across much of eastern Oregon and far southeast Washington, for all elevations, before the low tracks northeast into the Intermountain West and out of our CWA through Wednesday evening. The ECMWF EFI for snowfall is low (0.5- 0.7) across the region, indicative of low agreement among members in an unusual event, but SoT is 1-8 across the Columbia Basin and foothills of the Blue Mountains. This implies some members are forecasting rather extreme snowfall totals relative to climatology. Precipitation chances will taper off through the evening Wednesday as the upper-level low ejects east into the Intermountain West. Unseasonably cold temperatures will be the main concern through the remainder of the period. The ECMWF EFI is between -0.7 and -0.9 across our forecast area Wednesday through Saturday. Cloud cover will play a significant role in temperatures, especially if low- level stratus can set up across the Columbia Basin. That said, below- normal temperatures are very likely (90% chance), and the NBM is currently suggesting 10-20 degrees below normal. Thursday through Friday, upper-level ridging is suggested by ensemble means across the Pacific Northwest. However, the favored solution among ensemble clusters (38% of members) and the 12Z deterministic ECMWF do show some shortwave troughing which may suppress the ridging through Friday. Ensembles still indicate significant uncertainty in the longwave pattern heading into the weekend, particularly regarding the potential breakdown of the upper-level ridge and an incoming closed low in the Pacific. Some members bring the low onshore into Oregon and California, while others advertise the ridge persisting through the weekend. Plunkett/86 && .AVIATION...00Z TAFs...Later this afternoon through the evening, conditions are forecast to degrade to MVFR as lowering ceilings and -RA impact most terminals, with -SN at BDN/RDM and possibly a mix at YKM. HREF probabilities indicate low chances of IFR conditions (<10% for PDT/DLS/YKM/ALW/PSC; 20-30% chance for BDN/RDM) this afternoon and evening as the band of precipitation goes through. Winds are forecast to be around 10 kts or less through the period, except for BDN/RDM/ALW which will see some southerly gusts to around 25-35 kts at BDN/RDM and 20 kts at ALW through the evening. Plunkett/86 && .PRELIMINARY POINT TEMPS/POPS... PDT 31 49 24 37 / 60 10 10 10 ALW 34 49 26 41 / 70 10 10 10 PSC 37 48 30 40 / 60 10 20 10 YKM 26 40 25 36 / 50 30 30 10 HRI 33 50 28 39 / 60 10 20 10 ELN 25 37 23 35 / 60 40 40 10 RDM 24 43 22 36 / 80 10 20 30 LGD 28 40 23 40 / 70 20 10 10 GCD 25 41 24 43 / 70 10 20 30 DLS 33 48 31 41 / 50 30 30 30 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until 10 PM PST this evening for ORZ509. WA...None. && $$ SHORT TERM...74 LONG TERM....86 AVIATION...86