Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/18/20


Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
531 PM MDT Thu Sep 17 2020 .AVIATION... 00Z TAF CYCLE VFR conditions will continue at all TAF sites through the next 24 hours with light winds and mostly clear skies. Elevated smoke will be visible mainly across eastern NM Friday at sunrise. && .PREV DISCUSSION...233 PM MDT Thu Sep 17 2020... .SYNOPSIS... Expect some warming with mostly sunny skies and above normal temperatures through the weekend as high pressure moves south over the Land of Enchantment. Only isolated late day showers or storms are forecast across the high terrain through Sunday, with mostly sunny and hazy skies. Above normal temperatures will persist next week, with increasing chances for showers and storms around mid week as a disturbance moves southwest across the state. && .DISCUSSION... SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)... With the H5 high centered near the Four Corners, dry, northerly flow continues over the area. Some cumulus has developed over southeast NM, and some light shower or thunderstorm activity will be possible through about 00Z/01Z over southern Chaves County. Otherwise, a quiet night will be in store with clear skies and light winds on tap. The latest runs of the HRRR smoke continue to transport smoke from the wildfires across the western CONUS into eastern NM. This smoke will all be upper-level smoke, but did make a mention of haze across the east tonight. A Pacific storm system moves ashore the PacNW coast on Friday which will shift the area of high pressure into southern NM. This will allow surface winds to shift southeasterly across the east, but otherwise, Friday will be very similar to today. Near normal temperatures with mostly dry conditions are in store again aside from the possibility of a storm or two across the Sangres. LONG TERM...(SATURDAY THROUGH THURSDAY)... This weekend will feature a weakened upper high lingering over the state as a Pacific low/trough progresses east across the northern and central Rockies and ejects into the northern and central Great Plains. Temperatures will generally be above normal across New Mexico with isolated daytime heating triggered convection over the high terrain. High pressure aloft will continue to weaken Monday and give way to the westerlies, with no significant change to the sensible weather. An upper level ridge is forecast to build over California and the Great Basin from mid to late next week, but the 12Z medium range model solution are at odds with the path and amplification of an upper level trough dropping south along the front range of the Rockies around the upper high circulation. The 12Z GFS in particular is fairly wet for our area Wed/Thu with the upper high well to the north and low pressure aloft to our south in what looks like a developing Rex block. Will hold onto fairly minimal PoPs for next Wed/Thu for now given lack of run-to-run consistency and differences among the medium range solutions. Temperatures should remain above normal through at least the middle of next week. 15/11 && .FIRE WEATHER... No fire weather concerns are in the forecast through the next week. Mostly quiet weather conditions are expected through the weekend as temperatures remain near normal. As a storm system tracks across the Rockies, there may be enough moisture to allow for isolated storms across the northern mountains each afternoon. However, wetting precipitation is not likely. Mostly dry conditions will continue into next week aside from isolated storms across the western and northern high terrain along with the potential for some wetting precipitation. 15 && .ABQ WATCHES/WARNINGS/ADVISORIES... None. && $$
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
619 PM CDT Thu Sep 17 2020 .UPDATE... Issued at 618 PM CDT Thu Sep 17 2020 Increased sky cover east of the Missouri this evening. Otherwise, the forecast remains on track and no further changes were made. && .SHORT TERM...(This Evening through Friday Night) Issued at 153 PM CDT Thu Sep 17 2020 Not much going on in the next 24-36 hours. Currently have a deck of thin mid clouds across the northeast CWA and a decent area of smoke aloft across south central counties. The clouds will dissipate for the most part tonight, and the HRRR shows smoke backing northwards for Friday. As such will continue with partly cloudy mention. There will also be a small uptick in temperatures and dewpoints for Friday. .LONG TERM...(Saturday through Thursday) Issued at 153 PM CDT Thu Sep 17 2020 At this point, deterministic and ensemble solutions are relatively static in terms of synoptic-scale features Saturday through Thursday. An upper level ridge moves across the country`s mid- section through Saturday night, and then upper level troffing/height falls moves across the country`s northern mid-section Sunday/Sunday night. A dirty (flat) ridge or semi-zonal flow sets up Monday through Tuesday night, before a transient mid-level shortwave passes over the region late Tuesday night through Wednesday evening. Still looks like a much more formidable upper level ridge is forecast to build over the CONUS by the end of the week. Lower bound probabilities remain for some iso`d/sct`d coverage of showers or thunderstorms with the Sunday/Sunday night period of height falls/west-southwest flow and then again mid-week with the transient mid-level impulse. Otherwise, things look pretty dry in the out periods. Still advertising considerable warmth from Saturday through Thursday. The post-frontal airmass Sunday night into Monday, at this point, does not look to provide much in the way of relief from the warmer conditions. Notable mention: last night`s operational deterministic ECMWF solution generated a considerably different (colder) solution for mass fields and (more amplified) steering flow pattern aloft for Wednesday/Thursday; different compared to other models` solutions as well as its own ensembles output, which maintain a large upper level ridge developing and low level warm air advecting over the center of the CONUS by the end of the week. The ECMWF`s box and whiskers plot of last night`s envelope of solutions revealed the deterministic ECMWF`s output was the coldest (outlier) of any solution produced. Thus, will exclude the 17th/00Z operational deterministic run of the ECMWF from consideration with this forecast package. && .AVIATION...(For the 00Z TAFS through 00Z Friday Evening) Issued at 618 PM CDT Thu Sep 17 2020 Terminals KABR,KATY,KPIR,KMBG VFR conditions are expected through the period. However, elevated smoke will continue to stream over the region. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Wise SHORT TERM...Connelly LONG TERM...Dorn AVIATION...Wise
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1010 PM EDT Thu Sep 17 2020 .SYNOPSIS... The remnant low of Sally will move from across the Carolinas tonight and off the Mid Atlantic coast during Friday. Strong high pressure will build into the region from the north northeast Saturday through Sunday. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... As of 715 PM EDT Thursday... Latest analysis shows the center of post tropical cyclone Sally over South Carolina, with a warm front extending northeastward into North Carolina just south of our area. A shield of moderate to locally heavy rain extends N/NE of the center and has been impacting our entire area this afternoon into early this evening. Overall the rainfall rates haven`t been that impressive, but the cumulative effect of the rain over more than several hours is starting to cause some minor flooding issues, especially in urban areas. The area to focus on overnight is the southeast portion of the area for a couple reasons. First, the CAMs are still in fairly good agreement that an area of heavier rain will move through SE VA and NE NC overnight as the low moves N/NE across NC. Second, as the low moves closer to the area overnight, the warm front will try to nudge north to the vicinity of the NC/VA line. RAP forecast helicity south of the front increases over NE NC after about 03Z. So in addition to the flooding threat, there will be a marginal tornado threat over at least NE NC and possibly far SE VA overnight into early Friday morning. An additional 2-4 inches of rain is likely overnight over the southern two-thirds of the area, bringing overall totals to roughly 3-6 inches. The Flash Flood Watch will continue through early tomorrow evening for much of the area excluding roughly the northern third (north of Richmond). Low temps overnight range from the lower 60s NW to lower 70s SE. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... As of 420 PM EDT Thursday... The remnant low will push farther ene and into the Atlc during Fri. Rain will taper off and end from NW to SE Fri into Fri evening, with improving sky conditions also. Highs 70 to 75. Strong high pressure will then build into the region from the NNE Fri night through Sun. This will provide dry and cool autumn weather across the region, esply Sat through Sun. But, breezy to windy NE winds will prevail, esply along the Bay and coast. Lows Fri night will range from the upper 40s NW, to the lower 60s SE. Highs will mainly range from the mid 60s to near 70 Sat and Sun. Lows Sat night will range from the mid 40s NW, to the upper 50s/near 60 SE. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... As of 400 PM EDT Thursday... A deep upper trough is progged to be centered from NE Canada SSW to New England at the start of the medium rage period (Sun night). At the surface, strong high pressure (~1036mb) will be centered over nrn new England, ridging SSW into the Mid-Atlantic/Southeast CONUS. We will likely remain under the influence of the high through at least Wed AM as Hurricane Teddy is progged to track northward from well off the SE CONUS coast to near the Canadian Maritimes from the early to middle part of next week. The 12z/17 models are in decent agreement that a shortwave trough that will be just off the Northeast US coast on Mon will merge with TC Teddy near the Canadian Maritimes by Tue or Wed. Locally, it will generally be dry but with below average temperatures through much of the medium range period, as onshore (mainly NE) flow prevails. Breezy conditions will be possible near the coast through the early part of next week before winds subside a bit by Wed as the surface high becomes centered closer to our area. Will keep slight chc PoPs for far SE zones on Mon for perhaps a shower or two. Otherwise, it will average partly- mostly cloudy near the coast/partly-mostly clear inland from Mon- Tue, with more sun than clouds across all areas by the middle of next week. Highs on Mon will only range from the mid 60s to around 70F. Lows Mon/Tue AM will likely be in the mid 40s-near 50F along/west of I- 95, with 50s over ern portions of the CWA (and lower 60s at the immediate coast in SE VA/NE NC). A modest warming trend starts on Tue and continues through the middle of next week. Highs Tue generally in the upper 60s-low 70s with highs warming into the mid 70s by Wed. Still cool Tue night w/ lows in the mid-upper 40s across the wrn two-thirds of the CWA with 50s-near 60F closer to the coast. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... As of 715 PM EDT Thursday... Poor flying conditions overnight with widespread rain and low stratus across the region in relation to the remnants of Sally. Expect IFR/MVFR ceilings and visbys overnight through Friday morning, before conditions slowly improve by the end of the TAF period as the low moves off the coast and high pressure builds in from the NW. Winds are mainly E/NE this evening becoming N/NE on Friday. Wind speeds increase to 10-15 kts with gusts 20-25 kts on Friday. OUTLOOK... Strong high pressure builds into the region this weekend. Mostly VFR conditions expected, although breezy conditions will continue near the coast. && .MARINE... As of 400 PM EDT Thursday... The remnants of Sally will slowly track north towards the region through this evening and tonight and then tracks near the VA Capes early tomorrow morning. Currently seeing E to SE winds around 10 to 15 knots over the waters this afternoon. Seas range from around 3 to 4 feet, while waves in the Bay range from 1 to 2 feet (3 feet at the mouth). Winds will continue to increase this evening and tonight and become E to NE as the remnant low approaches from the south. Small Craft Advisory conditions are expected to begin as early as 00z for the Chesapeake Bay and southern coastal waters due to winds increasing to 15 to 20 knots and seas building to 5 feet. Winds will be on the increase through the overnight hours, increasing to around 20 to 25 knots and becoming northerly (as the low moves offshore) Friday morning. After collaboration with Morehead City, have replaced the Gale Watch for the southern coastal waters/Currituck Sound with a Gale Warning starting Friday afternoon and persisting through the weekend. Opted to keep the mouth of the Bay out of the initial Gale Warning (but did drag the Gale Watch back to Sunday) as latest local wind probs are not overly excited with Gale gusts during the first surge tomorrow for this location. Friday and Saturday will both feature N to NE wind around 20 to 25 knots with gusts of 30 to 35 knots for a majority of the waters (25 knots with gusts of 35-40 knots south). Some gusts in excess of 35 knots will be possible at the typical elevated sites during this timeframe, but not widespread enough to expand Gale headlines at this time, will keep high-end SCA wording for all areas minus the southern coastal waters/Sound where the Gale Warning is in effect. The gradient tightens Sunday into Sunday night allowing for additional gale gusts during this timeframe. Gale headlines may need to be expanded to include other portions of the coastal waters and lower Bay during this time frame (for now have high-end SCAs running into Sunday morning). The gradient finally starts to relax Monday into Tuesday with a decreasing trend in winds expected during this timeframe. Given this extended period of long-fetch NE flow, waves and especially seas will be a concern starting tomorrow and lasting well into next week. Seas build to 5-7 tomorrow afternoon, 6-10 ft by Saturday morning, and 8-12 ft by Sunday. Hurricane Teddy (well offshore) will add additional energy to the mix on Monday with seas ranging from 10-15 ft. Waves in the bay will increase accordingly with 4-5 ft on Friday, 4-6 ft on Saturday and Sunday with 5-8 ft becoming likely near the mouth of the bay. Seas likely remain in excess of 5 feet into at least the middle of next week. && .TIDES/COASTAL FLOODING... As of 1000 PM EDT Thursday... Water levels this evening are running about 0.5-1 FT above normal astronomical tide levels in advance of the remnants of Sally and this is expected to continue overnight before trending upward even further. This then puts most locations near minor flood stage on Friday. So as a result have issued a coastal flood advisory for the entire area for the high tide cycles on Friday through Friday night. However, the coastal flood threat is expected to increase on Saturday through early next week as persistent northeasterly flow is will push water toward the coast with the southern and western portions of the Bay and coastal areas from Wachapreague south expected to see the highest water levels. So have issued a Coastal Flood watch for this area from Saturday through Monday morning. Will continue to monitor the development of the NE winds over the next 24 to 36 hours as the watch may need to be upgraded to a warning later on Friday or Friday night. The remainder of the area is also expected to see above normal water levels with minor flooding expected to the coastal flood advisory for the remainder of the area will likely need to be extended through the coming weekend too. .HYDROLOGY... As of 1000 PM EDT Thursday... Expect sharp rises on area rivers over the next few days given the expected heavy rainfall through Friday morning. Minor river flooding is expected on the Meherrin, Nottoway and Blackwater Rivers by Saturday, except for the Meherrin River at Lawrenceville which should reach minor flood stage by early Friday morning. A flood warning is now in effect there. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...Coastal Flood Advisory from 8 AM Friday to 8 AM EDT Saturday for MDZ021>025. NC...Coastal Flood Watch from Saturday morning through Monday morning for NCZ102. Flash Flood Watch through Friday evening for NCZ012>017- 030>032-102. Coastal Flood Advisory from 8 AM Friday to 2 AM EDT Saturday for NCZ102. High Surf Advisory from 11 PM Friday to 2 AM EDT Monday for NCZ102. VA...Coastal Flood Watch from Saturday morning through Monday morning for VAZ077-078-084>086-089-090-093-095>098-100- 523>525. Flash Flood Watch through Friday evening for VAZ060-061- 065>069-078>090-092-093-095>100-512>516-518-520-523>525. Coastal Flood Advisory from 11 AM Friday to 5 AM EDT Saturday for VAZ089-090. Coastal Flood Advisory from 8 AM Friday to 8 AM EDT Saturday for VAZ099. Coastal Flood Advisory from 8 AM Friday to 2 AM EDT Saturday for VAZ093-095>098-100-523>525. High Surf Advisory from 11 PM Friday to 2 AM EDT Monday for VAZ098. Coastal Flood Advisory from 10 AM Friday to 5 AM EDT Saturday for VAZ075-077-078-084>086. MARINE...Small Craft Advisory until 7 AM EDT Sunday for ANZ630>632-634- 638-650-652-654. Small Craft Advisory until 1 PM EDT Friday for ANZ633-656-658. Gale Warning from 1 PM Friday to 1 PM EDT Monday for ANZ633- 656-658. Small Craft Advisory until 7 PM EDT Saturday for ANZ635>637. Gale Watch from Sunday morning through Monday morning for ANZ634. && $$ SYNOPSIS...TMG NEAR TERM...CMF SHORT TERM...MPR/TMG LONG TERM...ERI AVIATION...CMF MARINE...AJB/RHR TIDES/COASTAL FLOODING...AKQ
Area Forecast Discussion
National Weather Service La Crosse WI
624 PM CDT Thu Sep 17 2020 .SHORT TERM...(This evening through Friday) Issued at 207 PM CDT Thu Sep 17 2020 Another quiet day across the region under northwest flow aloft with surface high pressure building in. Satellite imagery showed some additional smoke moving into the area, but experimental HRRR indicated it would be remaining aloft in the forecast area. Otherwise, the main issue in the short term is the cooler temperatures and frost potential tonight. Skies look to remain clear tonight as high pressure continues to build in. This sets up for some pretty good radiational cooling, with the favored cold areas near and north of I-94 getting down into the lower 30s. A Frost Advisory has been issued for those areas. Expect another cool, quiet day on Friday, with highs in the 50s and 60s. .LONG TERM...(Friday night through Thursday) Issued at 207 PM CDT Thu Sep 17 2020 Expect another night with some frost potential in the favored cold areas Friday night. Otherwise the long term period still looks pretty quiet. High pressure will start pushing off to the east Saturday as a tightening pressure gradient leads to strengthening southerly return flow. By Sunday, model soundings show 35 to 40 mph winds at the top of the mixed layer, so would expect some fairly gusty winds at times through the weekend, especially in the open spots. In addition to the southerly flow, upper level ridging will build in, leading to increasing temperatures into the beginning of next week. Expect widespread highs in the 70s by Monday or Tuesday followed by a few lower 80s on Wednesday. As far as precipitation chances go, models continue to trend toward the dry side. A weak surface boundary will approach the area from the west sometime Sunday into Monday, but guidance is in good agreement of any associated precipitation dissipating as it moves in, owing to dry air in the lower levels. Another boundary looks like it might slide through and bring some rain chances sometime Wednesday or Thursday per several GEFS members and the 17.00Z ECMWF. However plenty of other guidance remains dry during that timeframe, so confidence is quite low. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 624 PM CDT Thu Sep 17 2020 VFR conditions are expected through the TAF period. Mid-level clouds currently located from South Dakota eastward into western Wisconsin will gradually slide south tonight, parting way to mostly clear skies. Some indications that low clouds may spread west from eastern Wisconsin toward the KLSE airfield on Friday morning, though if they do they should be scattered in nature. Winds will remain on the lighter side gradually turning from a northerly direction overnight to an east-southeast direction by Friday. Some cumulus clouds should develop by the afternoon hours on Friday with daytime heating. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...Frost Advisory from 1 AM to 8 AM CDT Friday for WIZ017-029-034- 042>044. MN...None. IA...None. && $$ SHORT TERM...CA LONG TERM...CA AVIATION...NMB
Area Forecast Discussion
National Weather Service Denver/Boulder CO
808 PM MDT Thu Sep 17 2020 .UPDATE... Issued at 759 PM MDT Thu Sep 17 2020 Upper ridge aloft remains entrenched across the region this evening. There was some cumulus in the mountains early this evening but that was about it, and of course along with the smoke in most areas. There is a weak surge that is moving through the northeast plains this evening with some enhancement of the northeast winds behind it. This surge is just now moving into the northern I-25 corridor. There is a weak pressure rise behind it through Nebraska. The surge, however may bring in more smoke later tonight and at least through Friday morning according to the latest HRRR smoke output. Similar conditions expected on Friday in terms of temperatures, dryness and smoke. && .SHORT TERM...(This evening through Friday) Issued at 240 PM MDT Thu Sep 17 2020 Dry air within a mid to upper level ridge over the Desert Southwest has resulted in quiet weather across Colorado today. Smoke levels have decreased from yesterday with visibilities about 2 to 4 miles better across the majority of our forecast area. This has allowed for better solar heating with temperatures climbing to 5 to 10 degrees above normal highs. The only fire in Colorado producing substantial smoke is the Middle Fork Fire. Smoke from this fire will continue to drift east-southeastward over portions of the northern Front Range Mountains the rest of today and will do the same thing tomorrow. Tonight, temperatures will be 5 to 10 degrees above normal with skies clearing. The HRRR-smoke model has near-surface smoke increasing later tonight and into tomorrow morning. Then, with better southerly low level flow developing tomorrow, the smoke decreases during midday and into the afternoon following a similar pattern to today. Haze and areas of smoke were added to the forecast to account for the continued poor air quality. Our forecast area will be under the influence of the aforementioned ridge again tomorrow. Weak lee cyclogenesis will develop just east of the mountains across Montana, Wyoming, and Colorado. This will increase southerly flow and bring in slightly warmer low level air. Highs tomorrow will be 2 to 4 degrees warmer than today with highs reaching the upper 80s in Denver. No precipitation is expected with mostly sunny skies. .LONG TERM...(Friday night through Thursday) Issued at 152 PM MDT Thu Sep 17 2020 Warm, dry and smoky conditions are expected to continue for the majority of the forecast period. Forecast period will start with most of Colorado remaining under the influence of an upper level ridge. A trough centered over WA/OR will then swing east/northeastward through the day Saturday, which will shift winds out of the southwest through much of the day. This will alleviate some of the ongoing smoke/haze over much of the plains. Lessened smoke, combined with fairly warm mid-level temperatures (13-14C at 700mb), and at least some downslope component to the wind will provide the Denver metro with a shot at hitting 90 during the afternoon. There will also be some weak synoptic forcing across the northern third of CO as the trough lifts northeast out of Wyoming during the afternoon/evening, so at least a few scattered showers/storms expected across the higher terrain. Gusty winds may also be a concern in the afternoon as mid-level winds increase. Overall weather pattern won`t change much for Sunday as flow stays SW/west through much of the day. Expect another round of showers/storms for the mountains, with no precipitation expected for the I-25 corridor and points east. Temperatures will be a little cooler than Saturday, with highs in the mid 80s for much of the plains. A brief period of more zonal flow is expected early next week. Mid-level moisture will increase slightly which should allow for somewhat better coverage of storms across the higher terrain through at least Tuesday. Afterwards, ridging should build back somewhere over the west coast. While most guidance is in good agreement that a ridge develops, there is less confidence in the strength and position of the ridge. Some models suggest potential for late week temperatures to again reach the upper 80s to perhaps low 90s, while others are considerably cooler with late week temperatures. Given the uncertainty this far out, today`s forecast closely matches the previous forecasts and is near the middle of the road of guidance. Regardless, highs in the 80s for the plains will be the theme for the foreseeable future, with no substantial rainfall chances. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 759 PM MDT Thu Sep 17 2020 Surface winds will be shifting northeast through 04z behind a weak frontal surge moving in from the northeast. Winds expected to gradually shift back northwest after midnight and then becoming light southerly by dawn. This surge may actually bring in more smoke later tonight and Friday morning with surface visibilities expected to drop between 5-6sm. Some improvement by Friday afternoon but still slant wise visibilities with smoke may affect approaches. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Entrekin SHORT TERM...Danielson LONG TERM...Hiris AVIATION...Entrekin
Area Forecast Discussion
National Weather Service Cheyenne WY
911 PM MDT Thu Sep 17 2020 .UPDATE... Issued at 857 PM MDT Thu Sep 17 2020 Updated the evening forecast package to include smoke and haze through Friday night. HRRR experimental model guidance showing light to moderate smoke concentrations through Saturday morning most likely. Remainder of forecast package left the same as overnight temperatures and dry conditions can still be expected. Newest development this evening is the Mullen Fire in SE Carbon County. As of 9pm MDT, it is less than 100 acres, with mostly dead/down timber in the area surrounding the fire. Continued weather forecast support in coordination with the U.S. Forestry service for this developing fire is likely. Satellite imagery that shows the "hot spots" regarding warmer surface fire temperature looks like it is has spread the last few hours. Overnight low temperatures across the forecast area will be chilly with readings in the 40-50 F range. && .SHORT TERM...(This evening through Friday) Issued at 230 PM MDT Thu Sep 17 2020 Fire weather concerns the issue in the short term. Stronger winds are an issue for Saturday as well. Currently...Low pressure system analyzed east northeast of Chadron in southwestern South Dakota this afternoon. Front has migrated east into northeastern Wyoming and west central Nebraska this afternoon. Surface high over western Colorado through western Wyoming. Smoky conditions continue over much of the area as upper high pressure system remains over the Rockies...with smoke from western wildfires moving in on the northern periphery of this ridge. An AQA for poor air quality has been continued today through noon across southeast Wyoming with a Special Weather Statement for the Panhandle. For Friday...Southwest winds return to Carbon County. Very similar to this past Tuesday when we hit RFW criteria for some areas of Carbon County. Seeing 20-25kts of wind mixing down from the GFS Rawlins sounding. In fact...the winds look a little stronger than this past Tuesday...so decided to issue a Red Flag Warning for northwest and southwest Carbon County. .LONG TERM...(Friday night through Thursday) Issued at 150 PM MDT Thu Sep 17 2020 GFS continues to show a strong low pressure system moving into western Montana Saturday. This is a very favorable pattern for winds in southeast Wyoming. GFS 700mb winds increase to 35-40kts across Carbon County Saturday afternoon. GFS soundings showing the possibility of 45-50kts mixing down from 575mbs...so would not be surprised to see some of our WYDOT sites hit high wind warning criteria. Will address that tomorrow if later model runs continue to show this. Much cooler temperatures Saturday night into Sunday as 700mb temperatures fall to around 5C behind the associated front. Much cooler temperatures Sunday with highs in the 60s and 70s. A windy day Sunday with 700mb winds still 35-40kts. Model guidance on winds way underdone...so had to manually raise wind substantially on the order of 10-15 mph to catch these stronger winds. && .AVIATION...(For the 00Z TAFS through Friday afternoon) Issued at 555 PM MDT Thu Sep 17 2020 Haze and smoke will continue to be the primary concern for Aviation over the next 24 to 36 hours. Hi Res guidance shows limited VIS between 3 to 6 miles across most of southeast Wyoming and western Nebraska through 18z Friday, but likely will continue through the afternoon hours. Winds will be relatively light and veer and gradually veer into the south overnight. HAZARDS/WEATHER TRENDS: Frequent MVFR VIS due to haze and smoke. Some improvement possible after 09z tonight, but not expecting much improvement in VIS, which will hover around 6 miles. && .FIRE WEATHER... Issued at 230 PM MDT Thu Sep 17 2020 Critical fire weather conditions expected Friday and Saturday across portions of southeast Wyoming. Starting off Friday...southwest winds return to Carbon County with gusty southwest winds Friday afternoon. A Red Flag Warning has been issued for FWZ 303 and 304 for Friday afternoon. A strong low pressure system tracks into western Montana Saturday...a very favorable pattern for strong winds across southeast Wyoming. Could see wind gusts of 40-50 mph across areas west of the Laramie Range Saturday. Some of these winds spill out into areas east of the Laramie range Saturday. So FWZ 310 was added to the Fire Weather Watch Saturday. Associated cold front with the low moves through Saturday night for cooler temperatures...higher humidity and low chances for showers Saturday night into Sunday. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Fire Weather Watch from Saturday afternoon through Saturday evening for WYZ301>310. Red Flag Warning from noon to 7 PM MDT Friday for WYZ303-304. NE...None. && $$ UPDATE...BW SHORT TERM...GCC LONG TERM...GCC AVIATION...TJT FIRE WEATHER...GCC
Area Forecast Discussion
National Weather Service Des Moines IA
626 PM CDT Thu Sep 17 2020 ...Updated for 00z Aviation... .DISCUSSION.../Tonight through Thursday/ Issued at 257 PM CDT Thu Sep 17 2020 Cool Canadian high pressure is currently centered over Manitoba with surface ridging south into the Midwest. This has led to cool northerly flow funneling into Iowa today with highs in the low 60s north to low 70s south. A fairly dense area of smoke has moved across the western half of Iowa this afternoon and is probably dense enough to filter enough solar energy to shave a few degrees off of highs today. Cool conditions again tonight though a region of mid- level clouds situated around 8 kft, will drift south out of Minnesota and should provide enough of a blanket to limit radiational cooling, despite likely holes in the cloud cover. Similar conditions like today are expected on Friday with a few more clouds but less smoke cover while the high pressure system settles into the eastern Great Lakes. The initial stages of warm advection will arrive on Saturday as the high begins its very slow move east and upper ridging approaches from the west. Breezy southerly winds with gusts over 25 mph are likely. In addition, the upper level transition to ridging will bring another dense layer of smoke over Iowa which could again impact temperatures by a few degrees despite the deeper mixing. The latest HRRR smoke simulations keep the smoke aloft as it passes across Iowa therefore, air quality impacts appear low. An upper low moving across the Pacific Northwest and into Saskatchewan and Manitoba this weekend will push the upper ridging east and will be replaced by warm westerly flow. As this occurs, the eastern surface high will dive south along the Appalachians leaving broad southerly surface flow across Iowa through much of next week. Temperatures will gradually warm through the 70s Sunday and into the low to mid 80s by mid next week. The orientation of the upper flow next week should push much of the smoke north of the state therefore should not have much impact on temperatures. A potential cool down towards the end of next week with ridging over the western CONUS buckling the westerly flow and leading to northwest flow into the Upper Midwest. At this time, the lone chance for precipitation is over far northern Iowa Sunday night as the upper low passes to the north and it is a very slight chance. && .AVIATION.../For the 00Z TAFS through 00Z Friday evening/ Issued at 626 PM CDT Thu Sep 17 2020 VFR conditions will persist throughout the TAF period with winds transitioning from northeasterly to easterly on Friday morning. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Donavon AVIATION...Hagenhoff
Area Forecast Discussion
National Weather Service Glasgow MT
807 PM MDT Thu Sep 17 2020 .DISCUSSION... Evening Update: The going forecast appears to be on track. Overnight temperatures may be a little cooler than models suggest with haze increasing slightly this evening under clear cloud cover overnight and light winds near the surface. Roxy Previous Discussion: Upper ridging will remain in place across the western U.S. extending into eastern Montana with northwest flow aloft. This will keep the thickest vertically integrated smoke and most concentrated surface smoke southwest of the CWA per latest HRRR guidance. That said, hazy sky conditions will likely continue over the next couple days. A Pacific trough will translate east toward the region with increasing chances for rain showers with isolated thunder Saturday night into Sunday. Wetting rains remain possible for portions of the area, especially near the Canadian border per latest ensemble means. The trough looks to lift northeast for the middle of the week with a return to more of a ridge pattern and drier weather conditions. Given increasing uncertainties at larger time scales, have kept closer to the consensus blends for now. && .AVIATION... FLIGHT CONDITION: VFR DISCUSSION: Dry conditions and light winds continue. Smoke and haze from western wildfires continues across the area. Conditions should remain at VFR, though slight visibility reductions are possible at times this evening. WINDS: Light and variable Thursday afternoon through Friday morning. A nocturnal, light easterly wind may set up overnight into the early morning at GGW. RMB/Roxy && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ weather.gov/glasgow
Area Forecast Discussion
National Weather Service Hanford CA
459 PM PDT Thu Sep 17 2020 .UPDATE... Updated AIR QUALITY ISSUES section. && .SYNOPSIS...Widespread smoke from regional wildfires will continue to impact the central California interior. Increasing southwest winds on Friday will bring gusty conditions over the higher elevations of the Sierra Nevada. A few showers are possible over the Sierra Nevada and adjacent foothills late tonight and Friday. Temperatures will cool to below normal levels Friday and Saturday then warm back to above normal early next week. && .DISCUSSION...The large four corners ridge which had provided our area with above normal temperatures for the past several days, is now breaking down as a strong upper level low pressure system approaches the PAC NW coast and carves out a trough off the western CONUS coast. A southwesterly flow ahead of the trough has picked up some upper level moisture from the remains of former Tropical Storm Karina and has spread it over central CA today. The increased cloud cover has resulted a temperatures cooling slightly from yesterday at most locations in our area. Meanwhile, smoke from nearby wildfires continues to reduce visibility across our area. However, as the trough moves inland and crosses CA on Friday, winds will pick up and the cooler air aloft will allow for some mixing to take place and will help significantly reduce the smoke presence. While the HRRR suggests that the winds will not be overly strong when they pick up on Friday, they might impact the large fires in the Sierra Nevada and might result in a period of increased spread during the afternoon and evening. This system will also bring cooler air into our area with temperatures expected to lower to below normal levels on Friday. The mid/upper level moisture from the remains of Karina could also produce some sprinkles or a few light showers in our area on Friday with the best chances over the higher elevations of the Sierra Nevada. The cooler airmass behind the trough will settle into our area on Friday night and Saturday which will result in cooler than normal temperatures and better overnight humidity recovery by Friday night. The models are in good agreement with building a flat ridge into our area on Sunday and Monday which will bring a warming trend to our area as temperatures recover to near normal on Sunday and rise slightly above normal on Monday. The warming trend will be short lived as a PAC shortwave pushes through the PAC NW on Tuesday. A stronger ridge is progged to build into CA next Wednesday and Thursday which will bring another slight warming trend to our area. Following the passage of the trough on Friday, dry weather is expected to prevail across our area from Friday night until at least next Thursday. && .AVIATION...Mainly MVFR visibility with areas of IFR visibility due to smoke in the San Joaquin Valley and in the foothills and higher elevations of the Sierra Nevada during the next 24 hours. The Tehachapi Mountains and Kern County Desert areas will have local MVFR visibility due to smoke during the next 24 hours. && .AIR QUALITY ISSUES... Please see SFOAQAHNX for an Air Quality Alert On Friday September 18 2020... Unhealthy in Fresno... Kern... Madera and Tulare Counties. Unhealthy for sensitive groups in Kings and Merced Counties. Very unhealthy in Sequoia National Park and Forest. Further information is available at Valleyair.org && .CERTAINTY... The level of certainty for days 1 and 2 is medium. The level of certainty for days 3 through 7 is medium. Certainty levels include low...medium...and high. Please visit www.weather.gov/hnx/certainty.html for additional information an/or to provide feedback. && .HNX WATCHES/WARNINGS/ADVISORIES... None. && $$ public...DS aviation....DS weather.gov/hanford
Area Forecast Discussion
National Weather Service Lincoln IL
821 PM CDT Thu Sep 17 2020 .SYNOPSIS... Issued at 613 PM CDT Thu Sep 17 2020 High pressure dominating the Upper Mississippi Valley will gradually move southeast over the next few days bringing dry and cooler temperatures into the weekend. && .UPDATE... Issued at 821 PM CDT Thu Sep 17 2020 No update required this evening. High pressure continues to build into Illinois. KCMI and KDNV have gusted a bit during the last hour, but as boundary layer decouples, winds should lose their variability. && .SHORT TERM...(This evening through Friday) ISSUED AT 139 PM CDT Thu Sep 17 2020 Band of lower level stratocumulus continues to shift south of I-72 early this afternoon, while clouds north of there show a decidedly diurnal pattern. Larger picture continues to show a widespread smoke plume overhead back into the Pacific Northwest. 12Z HRRR vertically integrated smoke plot shows this plume pushing south of our area on Friday, as the broad upper trough over the Great Lakes digs southward, bringing a temporary end to the hazy skies. Breezy northeast winds are expected into Friday, steadily bringing in drier air. This will allow most areas to dip below 50 degrees overnight, and remain below 70 degrees on Friday. .LONG TERM...(Friday night through Thursday) ISSUED AT 139 PM CDT Thu Sep 17 2020 The coldest conditions in this period are expected Friday night, with widespread lower 40s. Would not be surprised to see a few upper 30s sneaking in, especially north of I-74. While temperatures slowly recover during the weekend, lows in the 40s are likely into early next week. After that, the upper pattern becomes less clear. The GFS tends to build more of a warm ridge over the Plains, while the European model continues to advertise a very deep trough/low digging across the Midwest late Thursday night and significantly cooler temperatures. A couple tropical systems have the potential to make things murkier as well in terms of pattern shifting. Right now, only the European model is showing any rain potential, and that would not be until Thursday with the trough. With these variables, will keep the forecast dry for now, with warmer conditions moving in for mid week. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 613 PM CDT Thu Sep 17 2020 High pressure should dominate the terminals this TAF period. Northeast winds may gust at times by late morning Friday at the eastern terminals where the gradient ahead of the high is sufficient to produce gusts to 15-20 kts at times. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Barker SYNOPSIS...Barker SHORT TERM...Geelhart LONG TERM...Geelhart AVIATION...Barker
Area Forecast Discussion
National Weather Service North Platte NE
650 PM CDT Thu Sep 17 2020 .SYNOPSIS... Issued at 322 PM CDT Thu Sep 17 2020 H5 analysis from earlier this morning had a closed low over eastern portions of Hudson Bay. A trough extended south of this feature into the eastern Great Lakes. Further west, high pressure was anchored over southern California with a ridge extending north into southeastern British Columbia. West of this ridge axis, closed low pressure remained anchored off the coast of Oregon and has remained there over the past 24 hours. A trough of low pressure extended south of this low into the eastern Pacific-off the coast of northern California. Across the eastern CONUS, a decent shortwave was noted over northeastern Texas. East of this feature, the remnants of Hurricane Sally were located over northern Georgia. At the surface, low pressure was located over south central South Dakota. A warm front extended south of the low into the western Nebraska Sandhills, then south along the Kansas/Colorado border. This feature continue to slowly migrate east this afternoon, is the delineation between southerly and southeasterly winds east of the front and westerly winds to the west of the front. Once again, an abundance of elevated smoke, has led to hazy skies across the forecast area this afternoon. Visibilities were generally above 6 miles across the area, with some slightly lower visibilities noted in the panhandle and far western areas. Afternoon temperatures as of 2 PM CDT ranged from 71 at O`Neill to 79 at Valentine. && .SHORT TERM...(This evening through Friday night) Issued at 322 PM CDT Thu Sep 17 2020 Elevated smoke conditions and its effect on temperatures will be the main forecast challenge in the near term. Over the next 36 hours, the upper level trough of low pressure, currently off the Oregon coast, will come onshore Friday afternoon, migrating into central Washington and Oregon by Saturday morning. Downstream of this feature, ridging will build east to the Rockies. Not expecting much in the way of clouds with the ridge building into the central CONUS, however skies will continue to be hazy and smoky aloft, a result of fires in the western CONUS. Over the past couple of days, have good luck utilizing the HRRR smoke forecast by utilizing the Near Surface Smoke and 1FT AGL smoke products for surface smoke and Vertically Integrated Smoke for mid and high altitude smoke. That being said, based on the 12z forecast from this morning, near surface smoke should dissipate and shift west of the area tonight, keeping the area surface smoke free Friday into Friday night. As for smoke aloft, it will continue to remain in place over the next 36 hours. With that in mind, will continue to mention haze in the forecast mainly during the daytime hours. Will plan on modifying temps down some for Friday given the layer of expected haze. .LONG TERM...(Saturday through Thursday) Issued at 322 PM CDT Thu Sep 17 2020 Ridging will build east onto the plains Saturday with a bubble of warmer air pushing east. Highs Saturday will reach into the 80s and may approach 90 in the southwest. Late Saturday, a mid level trough of low pressure will track across southwestern Canada, dragging a trough through eastern Montana and northeastern Wyoming, into the western Dakotas. The base of this trough will track across northern Nebraska Saturday night, leading to an increased threat for thunderstorms. ATTM, not expecting much in the way of precipitation with this trough as boundary layer moisture continues to be very limited. A secondary threat for precipitation will arrive Sunday night, as an area of mid level frontogenesis and warm air advection over spreads the forecast area. The current forecast has this handled well and no changes will be made to the inherited forecast. Beyond Sunday night, a low amplitude ridge will build back into the central CONUS. This will lead to warmer than normal temps and mainly dry conditions. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 647 PM CDT Thu Sep 17 2020 VFR conditions will continue across much of western Nebraska with mostly clear skies expect for elevated haze impacting portions of the area. Favored areas will be northwest of a surface boundary expected to set up along an Ogallala to Ainsworth line overnight. This will lead to continued low-end visibility reductions at VTN until the frontal boundary shifts out of the area early Friday morning. Breezy winds are then expected to develop with gusts out of the southeast up to 20 mph possible Friday afternoon across north central Nebraska. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Buttler SHORT TERM...Buttler LONG TERM...Buttler AVIATION...Jurgensen
Area Forecast Discussion
National Weather Service Elko NV
324 PM PDT Thu Sep 17 2020 .SYNOPSIS...Widespread haze and areas of smoke from regional wildfires will continue to impact northern and central Nevada. A cold front will move across Nevada on Friday bringing cloud cover, gusty winds, and the chance of scattered showers and isolated thunderstorms. Quiet and cooler weather will follow over the weekend. && .SHORT TERM...Thursday evening through Saturday. Widespread haze and areas of smoke will contiue to impact northern and central NV tonight and Friday as indicated by HRRR smoke model. Satellite imagery shows plume of mid/high- level subtropical moisture is streaming northeastward from off the coast of central CA into western NV. This moisture will steadily increase ahead of a Pacific trough that will slowly move into the Northwest CONUS as a surface cold front works its way east across NV Friday afternoon and evening. Critical winds and low RH will exisit ahead of the front in White Pine and northern Nye County where a RFW is in effect. Cloud cover and smoke may serve to reduce daytime mixing elsewhere in central and northern Nevada so winds should not be quite as strong and gusty except in the higher terrain. Scattered showers and isolated thunderstorms will develop with the strong influx of moisture Friday afternoon and evening though instability will be very weak and elevated. Storms could start out dry before transitioning to becoming marginally wet. Temperatures will cool with the FROPA as daytime highs slip into the 70s and 80s Friday and 60s and 70s by Saturday. Overall, quiet weather and more seasonal temperatures will return for the weekend. There will remain a slight chance of a lingering shower developing in far northern/eastern Elko and eastern White Pine counties Saturday before moisture lifts entirely out of the state. .LONG TERM...Saturday evening through Thursday Evening. Post-frontal clear skies Saturday evening will lead to Sunday pre-dawn temperatures likely in the upper 30`s to lower 40`s, with some cooler spots in the valleys. Daytime temperatures are then expected to rebound for the beginning of the week, leading to temperatures some 5-10 degrees above average for this time of year. Upper ridge Thursday could have a 590 decameter center with near record highs in places. Big caveat is how much smoke? SW flow is expected through much of the week which will lead to areas of smoke and haze. Latest guidance suggests there may be areas of isolated dry thunderstorms in eastern NV Monday. Beyond Monday looks quiet with continued areas of smoke. Some model disagreement on Tuesday`s sensible weather: could have dry or could have isolated eastern Nevada storms. Holding off for now. && AVIATION...Smoke. Heat. Gusty afternoons. Visibility MVFR at KWMC and potentially KBAM. Reduced at KEKO but not below P6SM. KELY and KTPH also noticeably smoky but not restricted. Slant visibility will be reduced at all sites and en route. Some mountain partially obscured in northwest Nevada. Density altitudes higher than normal for the date. Outlook for the upcoming week: Smoke. Heat. Gusty afternoons. Monday afternoon and evening may see isolated thunderstorms and virga buildups in eastern Nevada. Higher than normal density altitudes continue after cooling off for the weekend. && .FIRE WEATHER...The Fire Weather Watch has been upgraded to a Red Flag Warning for winds and low RH for FWZs 425, 426, and 427 from 11am until 8pm PDT Friday. Elevated fire weather conditions will exist this Thursday afternoon and early evening as min RHs will be critically low at 5 to 10 percent, but afternoon breezes generally remain below criteria. Cold front moves across Nevada Friday afternoon and evening with a surge of mid-level subtropical moisture along the front that will produce scattered showers along with a mix of dry and marginally wet isolated thunderstorms that could produce a few lightning strikes. This will cause min RHs on Friday to rise above critical levels in all areas but FWZs 425, 426, and 427 where values will generally remain from 8 to 14 percent with pre-frontal southwest winds gusting up to 35 mph. Elsewhere, cloud cover and smoke should reduce the amount of daytime mixing and therefore the gustiness of the winds. Quieter weather with more seasonable temperatures and lighter afternoon breezes can be expected over the weeknd. && .LKN WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 11 AM to 8 PM PDT Friday for Central Nevada-Toiyabe-Northern Nye County-Mojave-White Pine and Northeast Nye Counties. && $$ 95/91/96/95
Area Forecast Discussion
National Weather Service Marquette MI
736 PM EDT Thu Sep 17 2020 .SHORT TERM...(This evening through Friday) Issued at 245 PM EDT THU SEP 17 2020 Latest RAP analysis indicate a mid/upper level low, seen at 500mb, near the east side of Hudson Bay resulting in broad cyclonic westerly flow through eastern Canada and the Great Lakes. Sfc ridging has extended from Manitoba into the Upper Mississippi Valley, bringing anticyclonic northerly flow across Lake Superior. 850 mb temps are around -1C which will limit highs this afternoon in low to mid 50s. A bkn cu field has developed but given drier airmass with high pressure building in and northerly flow, leaning towards keeping it generally mostly sunny with these clouds slowly filtering out. A pretty chilly night is ahead across Upper Michigan. With mostly clear skies, light winds, and high pressure in firm control over the region, temps should drop to around or below freezing for most inland locations with widespread frost likely. With that, have decided to issue a Freeze Warning for the entire cwa in coordination with neighboring offices as temps will range from the mid 20s to low 30s. Wouldn`t surprise me if a few spots dipped into the low 20s. Temps Friday will be similar to today with 50s across Upper Michigan with mostly sunny skies expected again. .LONG TERM...(Friday night through Thursday) Issued at 232 PM EDT THU SEP 17 2020 Upper air pattern consists of a 500 mb trough in the Pacific NW 00z Sat with a ridge over the Rockies and a broad trough over the ern half of the U.S. The ridge moves into the plains 00z Sun with the trough in the northern Rockies. The ridge then moves into the upper Great Lakes 00z Mon with the trough in the northern plains. Pretty quiet weather for this forecast. In the extended, the GFS and ECMWF show a 500 mb trough over the northern plains 12z Mon with ridging in the lower Great Lakes. This troughing moves into the upper Great Lakes 12z Tue. Troughing moves into the northern plains 12z Wed. This trough moves through the upper Great Lakes 12z Thu with a sfc cold front moving through. Temperatures will continue to be above normal for this forecast period and will be fairly quiet. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 734 PM EDT THU SEP 17 2020 With high pressure settling across the area, expect VFR conditions at all terminals through the TAF period. Winds will generally remain light with lake breezes developing during the day on Friday. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 245 PM EDT THU SEP 17 2020 High pressure settling in over the region today bringing nw winds generally below 15 knots except over the eastern half of the lake where gusts could get up to 20 knots through early Friday morning. Winds will fall back below 15 knots through Saturday before turning more southerly and increasing with gusts between 20-25 knots on Sunday as the lake will be in between high pressure just off to the east and low pressure to the west. This will continue into early next week. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Freeze Warning from 11 PM EDT /10 PM CDT/ this evening to 10 AM EDT /9 AM CDT/ Friday for MIZ001>007-009>014-084-085. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JH LONG TERM...07 AVIATION...Voss MARINE...JH