Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/25/16


Area Forecast Discussion
National Weather Service Denver/Boulder CO
955 PM MDT Mon Oct 24 2016 .UPDATE... Issued at 945 PM MDT Mon Oct 24 2016 Cloud shield on leading edge of the upper air system advancing acrs Utah this evening now nearing the Front Range according IR satellite imagery. Precip associated with this cloud cover still well back in Utah and mainly in the from of rain. Have adjusted sky coverage to speed up its arrival east of the mtns in the next few hours. Latest HRRR and RAP indicate spotty light QPF over and east of the Front Range between 09-15z/Tue. Amts appear very light...esply on the plains as the boundary layer should remain quite dry with downslope flow off the foothills. Should see gradual clearing through the day as is already indicated in the fcst grids. Otherwise few changes necessary to the ongoing forecast for tonight. && .SHORT TERM...(This evening through Tuesday) Issued at 352 PM MDT Mon Oct 24 2016 Forecast on track with the band of showers now across Utah slated to move across western Colorado tonight with whatever is left of it coming over eastern Colorado in the morning. Pretty good chance of mountain locations getting a little rain and snow as the band should stay together until it hits the east slopes. Not much cold advection so the snow level should be around 10 thousand feet, and at pass elevations roads should be wet for the most part. Expecting mainly virga east of the Front Range, but enough organization to keep some low PoPs in the morning. For the afternoon a shallow layer of moisture with just slight instability over the mountains. I dropped the PoPs a bit east of the mountains for the afternoon as the showers trying to move over the mountains should be weaker. Forecast temps look good with just a little cooling, as much due to cloud cover as anything else. .LONG TERM...(Tuesday night through Monday) Issued at 352 PM MDT Mon Oct 24 2016 Light snow and rain showers in the mountains will linger into the early hours on Wednesday. Snow levels could get down to 10,000 ft overnight but amounts will be very light. As the upper trough moves out some increased winds over the NE corner will be possible but no showers. Behind this feature strong ridging will move in bringing continued dry and above average temperatures to the region. Highs through Friday will be in the 70s on the plains with Thursday being the warmest with a possible high temp close to 80. Lows will be in the 40s. Both the GFS and EC have the trough axis over the NW with a trailing branch over Western portions of the state. This could bring a slight chance of precipitation to the mountains but with minimal QG and CAPE confidence is low on little if any accumulation with no precip expected on the plains. This feature will make its way out by late Saturday with another ridge settling in by Sunday. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 945 PM MDT Mon Oct 24 2016 VFR conditions at Denver area terminals next 24 hours. Although should see cloud ceilings lowering after midnight to possibly as low as 8000 ft agl with a weak upper air disturbance passing over the area. Could see a few light rain showers in and around the Denver metro area towards morning...but with no restrictions to visibility as the air near the ground should remain quite dry. Southerly winds of 7-14 kts across the metro area at this time should gradually swift clockwise to a west- southwest component after 09z with isolated showers moving down of the foothills. After the passage of these showers around 14-15z... should see winds briefly return to a southerly direction at 6-12kts...before gradually turning to a west-northwest direction around midday behind the passing weather disturbance. Should also see a steady reduction in cloud cover through the afternoon. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Baker SHORT TERM...Gimmestad LONG TERM...Bowen AVIATION...Baker
Area Forecast Discussion
National Weather Service Columbia SC
1044 PM EDT Mon Oct 24 2016 .SYNOPSIS... A cold front will move through the forecast area tonight with a reinforcing shot of cool air through Midweek. There is a slight chance of showers late in the week associated with a fast moving system forecast to move through the area. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... A dry air mass remains across the forecast area with just some high thin clouds ahead of the shortwave trough in the southern stream over east Texas. The cold front in the north part of the forecast area at 1000 pm will push south of the area around 200 am. The front will move through the region dry. Increased mixing over the relatively warm lakes will result in breezy conditions. The HRRR suggested wind close but just below lake wind advisory criteria especially on Lake Marion. Mixing in the boundary layer again tonight will limit net radiational cooling. Expect overnight lows similar to last night. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... A broad upper ridge will build over the Southeast. High pressure will ridge into the forecast area from the north at the surface. A cool and dry air mass will build into the region. Slightly below normal high temperatures are forecast, in the lower to middle 70s. Overnight lows in the 40s. && .LONG TERM /THURSDAY THROUGH MONDAY/... An upper-ridge over the center of the country will promote northwesterly flow aloft over the southeastern states through midweek. Surface high pressure will ridge into the area from the north Wednesday before shifting offshore Thursday. A surface low over the Great Lakes region early Thursday morning will shift northeastward toward New England. This system will bring a weak cold front across the area Thursday night/early Friday. Moisture will be limited throughout the period, so continued with a dry forecast except during the Thursday/Friday time frame maintained a slight chance. More dry high pressure will build in from the west late Friday into Saturday, with another dry cold front moving into the area Saturday night/Sunday. More high pressure will build in from the north Monday. Seasonable or above normal temperatures are forecast for much of the period. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... Very high confidence for VFR conditions throughout the TAF period. A dry cold front has moved into the northern Midlands and will continue across the forecast from 03z to 06z this evening. Calm winds will become N/NE with speeds around 5 knots. Observations in the Upstate and Carolina Piedmont show similar wind speeds. Models indicate 30 knot NE winds above the surface, around 1000 to 2000 ft. At this time it appears conditions will remain under the 30 kt LLWS criteria. But LLWS may need to be added to the TAFs if surface winds go calm later tonight. Tuesday, mostly clear skies and dry weather will continue. A few high clouds may continue to stream over the area. Expect NE winds from 5 to 10 kts throughout the day. EXTENDED AVIATION OUTLOOK...Restrictions possible Thursday and Thursday night as a weak cold front crosses the region. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$ SYNOPSIS...99 NEAR TERM...99 SHORT TERM...99 LONG TERM...99 AVIATION...99
Area Forecast Discussion
National Weather Service Goodland KS
523 PM MDT Mon Oct 24 2016 .SHORT TERM...(This evening through Tuesday) Issued at 232 PM MDT Mon Oct 24 2016 Main concern will be extent of fog/dense fog after midnight into tomorrow morning. High resolution guidance remaining consistent in developing fog with areas of dense fog appearing more likely. Since yesterday the area of fog continues to be a little further west with most of the area east of the Colorado border having a good chance. So I pulled the fog further west and having it last through mid morning tomorrow. Sref probabilities and other high resolution would support a dense fog advisory having to be issued for later on tonight. 12z and 18z Nam very consistent and the Nmm, which was capturing the wind field the best, were showing dense fog east of the Colorado border. Enough difference in the output that I was not certain enough as to the area to issue an advisory for with the eastern half having the best chance. Evening shift has been briefed and will watch closely. Overnight temperatures will be a function of how fast the stratus moves in. Eastern areas will be the warmest. Stratus hangs on in the east into the afternoon. Kept the blend high temperatures but possible that it could end up being a little cooler in the east than what is in there. Any precipitation looks to either be east of the area or waits to form until early in the evening. So kept the eastern locations dry for the afternoon hours. .LONG TERM...(Tuesday night through Monday) Issued at 214 PM MDT Mon Oct 24 2016 An upper level ridge continues to be the dominating feature during the long term period. This results in a mainly dry forecast, besides a slight chance for showers and thunderstorms across the extreme southeastern portion of the forecast area late Tuesday. Temperatures look to remain above normal in the 70s and even the low 80s. Tuesday night: A shortwave briefly breaks down the ridge, bringing shower and thunderstorm chances to the High Plains Tuesday evening. Better chances still appear to be east of the forecast area where moisture increases, but the init still has a slight chance clipping our southeastern CWA where there is limited instability. Wednesday through Thursday night: After collaboration with neighbors, winds were increased on Wednesday to account for higher speeds behind a cold front. The ridge quickly rebuilds behind Tuesday`s disturbance and the flow aloft becomes northwesterly. Dry weather prevails. Friday through Monday: Another disturbance passes across the northern Plains on Friday, sending a cold front south and shifting the flow to westerly. However, there is little moisture in place, so a dry frontal passage is currently anticipated. Should see somewhat cooler air move into the High Plains in time for the weekend as the upper ridge redevelops, with this pattern persisting into next week. Near zero PoPs continue during this timeframe. Temperatures: Highs gradually increase through Thursday, with temperatures in the low 80s across the majority of the area, before dropping into the upper 60s to low 70s on Saturday behind Friday`s system. The upper ridge rebuilds, and temperatures in the mid/upper 70s return for Monday. Low temperatures range from the upper 30s to low 50s during this period. Lows were decreased (particularly Friday and Saturday nights) considering the dry air mass that will be in place. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 516 PM MDT Mon Oct 24 2016 Main aviation concern will be chance for low clouds and fog overnight and into Tuesday morning. Old front will lift out this evening as a warm front, to be replaced by a surface trough near the Colorado/Kansas border overnight. Moisture pooling along and east of the trough and moisture advection on southerly winds will create an environment favorable for low level saturation. However... a couple of concerns. Mid and high level clouds are forecast to increase which may inhibit radiational cooling. Second, low level winds lack an upslope component. HRRR notably keeps low clouds and fog mainly in Nebraska. Nonetheless, will carry some visibility and ceiling restrictions around sunrise at both KGLD and KMCK, improving by mid morning as the trough moves out and westerly downslope winds develop. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...JBH AVIATION...024
Area Forecast Discussion
National Weather Service Houston/Galveston TX
835 PM CDT Mon Oct 24 2016 .DISCUSSION... An upper level shortwave trough was moving over Southeast Texas at 8:30 PM. Radar showed an area of possible sprinkles along and north of a line from Madisonville to Livingston. The latest HRRR model showed that this area should exit out of the forecast area later this evening. Tweaked the POPS and weather. Otherwise, the latest forecast was on track. 40 && .PREV DISCUSSION... /ISSUED 613 PM CDT Mon Oct 24 2016/ AVIATION.../00Z TAF/ Shortwave trough on water vapor satellite imagery is expected to move east tonight and shear out. This will allow for high/mid level clouds to clear out during the day tomorrow. High clouds may still be enough to limit the fog potential for the area in the morning. Possible there could be some patchy fog for KCXO/KLBX but not enough to put in TAF. Low level moisture return is not that strong so think TAFs will be VFR with any lower CIGS slow to develop if at all the next couple of days. Overpeck PREV DISCUSSION... /ISSUED 334 PM CDT Mon Oct 24 2016/ DISCUSSION... Mid afternoon temperatures across Southeast Texas under partly cloudy skies range from the lower to mid 80s inland to around 80 at the coast. Radar continues to show a couple possible eastward moving rain showers, but most of it continues to likely be virga. Disturbance associated with these radar echoes will continue moving eastward and out of the state tonight. Cannot totally rule out a shower or two across parts of our Gulf waters over the next couple of days, but chances right now look too low to include in the forecast. Still looking for mainly partly cloudy skies over the next several days with low temperatures ranging from the upper 50s to lower 60s well inland to the lower 70s at the coast and high temperatures in the lower to mid 80s. Mid/upper level ridging then builds across the state from the west and southwest toward the middle to end of the week and on into the weekend. This feature will keep a majority of Southeast Texas on the dry side with steadily warming and unseasonably warm temperatures (lows in the lower to mid 60s and highs in the mid to upper 80s...maybe even around 90 and possibly close to record highs). 42 MARINE... Light to occasionally moderate east to southeast winds are expected over the next few days, with seas generally in the 1-3 feet range. Seas are expected to build into the 3-5 feet range across the offshore waters this weekend as winds increase in response to a developing surface trough in the Bay of Campeche, but no flags are anticipated at this time. Isolated showers (and a thunderstorm or two will be possible by late week as an upper level disturbance moves into the northwest Gulf from the Southern Plains. Otherwise, expect tides one half to one foot above normal through the end of the week. Huffman && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 63 82 63 84 62 / 10 0 0 0 0 Houston (IAH) 61 83 62 85 64 / 10 0 0 0 0 Galveston (GLS) 71 82 72 82 72 / 10 0 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ Discussion...40 Aviation/Marine...39
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1156 PM EDT Mon Oct 24 2016 .UPDATE... Issued at 1157 PM EDT MON OCT 24 2016 With dewpoints still holding around 40 for most locations, looks like fog will be favored over frost tonight, so have removed any mention of frost from the forecast and stuck with patchy fog in the river valleys. Also, tweaked the colder valleys down a few degrees as we are already seeing some temperatures touching 40 on the nose. Being we are already approaching cross over temperatures, we may have to look at the possibility of some localized dense fog near the river valleys. We`ll continue to monitor satellite for any indications of some denser fog developing. With weak dry air advection, any dense fog would be confined to the more deeper sheltered valleys, where the dry air may not make it into these locations as easily. UPDATE Issued at 1054 PM EDT MON OCT 24 2016 Continuing to monitor falling temperatures this evening under this clear and stable regime. Updated the near term forecast to include the latest observations for temps and dew points to make sure they are well on track with current conditions once more. Rest of forecast continues to be in good shape. All changes have been published and sent to NDFD/web. A new forecast package was sent out to update to "rest of tonight wording", although content really didn`t change from previous package. UPDATE Issued at 747 PM EDT MON OCT 24 2016 Forecast seems to be in good shape at this time. Temperatures are quickly dropping off with the loss of daytime heating this evening. Loaded in the latest observations to make sure the near term forecast for temps and dew points matched up well with the ongoing conditions. Changes were not significant enough to warrant any new forecast products. Near term grids have been published and sent to NDFD/web. && .SHORT TERM...(This evening through Tuesday night) Issued at 445 PM EDT MON OCT 24 2016 19z sfc analysis shows a dry and mostly cloud free cold front settling through eastern parts of the state. This boundary is switching winds more completely to the north at 10 to 15 kts. Plenty of sunshine on either side of the front has led to near normal temperatures in the mid to upper 60s north to the mild lower 70s south while dewpoints were able to mix down into the upper 30s and lower 40s this afternoon. The models are in good agreement aloft through the short term as they all depict a broad trough lifting northeast and out of the area. This will allow heights to rise for Kentucky through Wednesday morning while energy and the next developing trough over the plains stay well north of the area. Accordingly, will favor the blended model solution with a lean toward the higher resolution HRRR and NAM12 versions along with the co-op MOS guidance. Sensible weather will feature a clear and cool night, especially after the post frontal winds die off. This will lead to a minor ridge to valley temperature difference tonight and a more significant one on Tuesday night as the sfc high shifts off to the east. This will allow for some patchy frost to develop in isolated spots of the deepest valleys both nights, though limited by the dry air expected Tuesday night. As such, the vast majority of the area of will stay frost free for another week. Additionally, both nights could see some patchy fog along the rivers towards dawn. Another pleasant and mostly sunny day can be expected for Tuesday with highs similar to today - warmest southwest and 5 to 10 degrees cooler northeast. Started with the CONSShort/ShortBlend for the bulk of the grids with adjustments to the night-time temps revolving around terrain differences, as well as knocking dewpoints down in the afternoon and again Tuesday night. PoPs were again zeroed out through the period - in line with all guidance. .LONG TERM...(Wednesday through Monday) Issued at 325 PM EDT MON OCT 24 2016 The extended period will feature a series of shortwaves embedded in the northern stream moving through the Ohio Valley. The first shortwave will make its way from the central plains across the Great Lakes late Wednesday night/Thursday, dragging a cold frontal boundary through Eastern Kentucky. This system will bring our next chance for precipitation by dawn on Thursday. However, operational models have continued to back off on the QPF potential with this frontal passage so most locations will only see a tenth of an inch or less. The upper level pattern becomes a bit messy beyond Friday with several additional impulses dropping through the Ohio Valley in west- northwest flow. Differences exist between the GFS and ECMWF with how far south and how strong these impulses become so have remained close to the CR Superblend solution from Saturday forward. That being said, there is the potential for a few showers Saturday afternoon and evening and again late Sunday night. Ridging builds back into the Tennessee Valley on Monday setting the stage for a few more days of dry and mild weather. Temperatures will remain near seasonable values through the period with highs in the upper 60s and low 70s. Morning lows will vary a bit more with potential cloud cover and passing showers. But most mornings, lows should be near climatology, in the mid and upper 40s. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) ISSUED AT 754 PM EDT MON OCT 24 2016 With high pressure and a dry airmass in full control during the TAF period, skies should remain clear save a few passing high clouds during the day tomorrow. Winds will become more NE overnight, and remain so through the day tomorrow, generally 5 knots or less. A few gusts up to 10 knots cannot be ruled out during the afternoon tomorrow. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...GREIF LONG TERM...JVM AVIATION...JMW
Area Forecast Discussion
National Weather Service Medford OR
804 PM PDT MON OCT 24 2016 .DISCUSSION...Updates were already issued this evening to adjust pops/weather and lower the wind headlines on the east side. No further updates are planned. The cold front has moved east of the area, and winds are diminishing as gradients relax. Gusty winds are still certainly occurring, especially over the mountains and open areas on the east side, but all obs are well below criteria and guidance suggests this trend continues tonight, so the high wind warnings and advisories were lowered. Evening radar shows thunderstorms edging into the coastal waters off Gold Beach associated with a vigorous shortwave moving through the area. The global models are too far west with the instability, but hi-res models such as the HRRR are picking up on this nicely and show this instability moving right up to the coast and then gradually shifting north tonight. The area of isolated thunderstorms was expanded to cover all the waters and just inland from the coast. Most of these areas will not see lightning tonight, but it certainly can`t be ruled out. Widespread showers are occurring from west-central Siskiyou County into the Oregon Cascades and sliding slowly east. Further west, showers have become more isolated except in the southwest-facing upslope areas where showers will likely continue all night. There will be a general downward trend in shower activity tonight over most valleys as most of the energy moves north and we find ourselves in between systems. Pops were adjusted as such. -Wright && .AVIATION...25/00Z TAF CYCLE...Mountains and terrain will be obscured tonight as cloud base lowers to MVFR with IFR cigs possible near rivers and streams. While MVFR cigs may not occur at the terminals themselves at the three inland TAF sites, there will be widespread MVFR cigs in the vicinity of these terminals. /FB Note: The ceilometer at FAA site KOTH is out of service, so there will be no ceiling observations available generally between the hours of 04Z and 14Z. && .PREV DISCUSSION... /Issued 258 PM PDT MON OCT 24 2016/ DISCUSSION... Short Term...Tonight through Thursday Night...Satellite and radar imagery show the front has passed through most of the West Side, and now is lies right along the spine of the Cascades. To the West, winds have diminished and precipitation continues as showers, with the heaviest precipitation along the southern slopes. To the East, steadier rain and gusty winds continue. Due to this, the wind headlines for the Rogue and Shasta valleys have been cancelled, but the ones for the East Side will continue into this evening, as the front slowly slides through. For more details on the updated wind headlines, see the hazardous weather message at PDXNPWMFR. The upper level low responsible for the wind and rain today will remain offshore, drifting slowly north tonight through Tuesday. A second trough will then swing under this one from the south, and slide north along the coast Tuesday night and Wednesday. This will bring another round of wind and rain to the area Wednesday morning. Although pressure gradients with this system are forecast to be lower and the surface low is not expected to deepen as it slides through, winds may still reach advisory levels in the Shasta Valley and over the East Side. Confidence is low, but further model runs this evening and tonight should tilt the scales in one way or the other. Precipitation is another matter. With models showing 6 to 12 hour differences in the timing of the front, and also depicting the chance that the front could stall along the coast for a brief time, there is a wide range of precipitation amounts that could result. have opted towards the slower solutions, due to the weaker dynamics and flows associated with the system, and brought the main band of precipitation onshore along the southern Oregon coast Wednesday afternoon, then gradually sliding it east through the evening and into Wednesday night. Rainfall amounts will be heaviest wherever this band stalls, with heaviest amounts along souther slopes and east to west trending ridgelines. West Side valleys will most likely be sheltered, and should only receive light amounts, while the bulk of the moisture inflow never really makes it east of the Cascades. Showers are then forecast to continue through Thursday as onshore flow continues, conditions should dry out a bit Thursday night as weak upper level ridging nudges into the region, but this break will be brief as another system approaches from the south, continuing the unsettled and wet pattern into the long term. -BPN LONG TERM...Friday through Monday...Models start this time frame in fairly good agreement with a closed 500 mb low at 39 N and 136 W at the same indicated 544 height. This first system of the extended period brings rain ahead of a warm front Saturday. The models remain in good agreement as the upper low moves down to about 100 nm offshore of Northern CA. This brings the triple point of this system directly over our forecast area Sunday. From there, models are in broad agreement with a deep upper level trough over the coastal waters off of the Pac NW, and the timing of systems will be impossible this far out and have broad-brushed chance pops through the remainder of the extended. -Sven MARINE...Updated 200 PM PDT Monday, October 24, 2016...Showers and isolated thunderstorms will continue through tonight. Behind the front later tonight, a strong low will approach the area but stay west to northwest of the waters. This strong low will help to maintain south Gales to the waters through Tuesday morning. Very high, very steep and chaotic seas will develop late this afternoon and tonight as a high and very steep west swell combines with very steep south winds seas. These conditions will continue through Tuesday morning. Winds will gradually lower Tuesday to small craft advisory levels, but very steep hazardous seas may continue into Tuesday afternoon then gradually lower. Another strong storm may bring additional gales and very steep hazardous seas to the waters on Wednesday. /FB && .MFR WATCHES/WARNINGS/ADVISORIES... OR...None. CA...None. Pacific Coastal Waters...Small Craft Advisory until 11 AM PDT Tuesday for PZZ356. Gale Warning until 11 AM PDT Tuesday for PZZ350-356-370-376. Hazardous Seas Warning until 11 AM PDT Tuesday for PZZ350-356-376. $$
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1032 PM EDT Mon Oct 24 2016 .SYNOPSIS... A dry cold front will move through from the north overnight followed by high pressure through mid week. A cold front will approach from the west on Thursday and cross the area Thursday Night and Friday. High pressure will build over the region Saturday with another cold front crossing Sunday. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... As of 1000 PM Monday...cold front has pushed through NE half of area but stronger post-frontal winds with CAA just reaching northern OBX, but still on track to spread across all areas by morning. Slack pressure gradient along front allowed temps to drop into mid 50s inland with radiational cooling and temps there will initially rise back to near 60 next few hours with increased mixing, but still expected to drop into mid-upper 40s by morning. /Previous discussion/ As of 7 PM Mon...Latest sfc analysis shows the dry cold front south of Albemarle Sound and will continue to push south through this evening. High pressure will start to build behind the front...bringing cooler and drier across the area and gusty NNE winds developing along the beaches. Overnight lows will range from mid 40s well inland where winds will diminish to mid/upr 50s beaches. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... As of 215 PM Mon...Dry high pressure will quickly build in from the NW keeping skies mainly clear. Thicknesses support forecast highs mainly in mid 60s. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... As of 3 am Mon...Surface ridge along the east coast will move offshore by midweek. A fast-moving cold front will approach from the northwest Thursday, passes through eastern NC Thursday night, then moves off the coast during the day Friday with precip ending quickly from the west. Bulk of energy and moisture pass by to the north, so have kept PoPs no higher than chance. Models disagree next weekend. The GFS brings another cold front w/showers through Saturday with high pressure building in Sunday. The ECMWF has a ridge to the south Saturday, then brings a dry front through Sunday, with the bulk of the moisture passing to the north. HPC favors the ECMWF solution, so have kept dry pattern going Friday into Sunday. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... Short Term /Through Tue/... As of 7 PM Mon...High confidence of VFR conditions will prevail through the TAF period. A dry cold front will cross the area tonight and keep any clouds to the east of the TAF sites if there are any. Dry high pressure will build behind the front from the NW late tonight under a light NNE flow...limiting fog development. Tuesday...expect mostly clear skies under northerly flow of 5-10 knots. Long Term /Tue Night through Sat/... As of 3 am Mon...VFR through Wednesday night. A fast-moving cold front will bring scattered showers (no thunder) through Thursday night then off the coast Friday. Bulk of shower activity will be Thursday night. Surface winds will be from the north around 10 knots Tuesday, northeast around 5 knots Wednesday, southeast around 5 knots Thursday and west around 5 knots Friday. && .MARINE... Short Term /Through Tue/... As of 1000 PM Monday...cold front currently moving across waters from north and stronger post-frontal north winds just reaching northern waters which is slightly slower than forecast. Adjusted winds with latest HRRR but still expecting 15-25 KT all waters 2 AM-5 AM and no change to SCA. /Previous discussion/ As of 7 PM Mon...Latest buoy obs are showing WSW 10-15 knots and seas 2-5 ft with the highest over the central waters. Made minor tweaks to the seas to reflect current trends. A dry cold front, currently south of the Albemarle will push south through this evening. A good surge of NNE winds will develop behind the front late this evening into Tuesday morning. Cont prev fcst trends with SCA developing most waters overnight with seas reaching around 6 feet outer waters. High pres quickly builds in from the NW Tue and expect winds to diminish and seas drop below 6 feet by around mid day. Long Term /Tue Night through Sat/... As of 3 am Mon...north winds will decrease Tuesday night into Wednesday as high pressure builds across the area from the north. Seas will subside to 3-5 feet Tuesday night as the pressure gradient loosens and winds diminish. As the high shifts offshore Wednesday, winds will veer to northeast Wednesday night, then from east to southwest Thursday as another cold front approaches from the west. The front will sweep through the marine zones Thursday night and off the coast Friday with winds veering to northwest. Winds and seas Tuesday night through Friday will be mostly light, generally 10-15 knots and 2-4 feet. Only exception will be Wednesday north of Ocracoke, where seas may temporarily build to 3-5 feet. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...Small Craft Advisory until 8 AM EDT Tuesday for AMZ130-131-135. Small Craft Advisory until 1 PM EDT Tuesday for AMZ150-152-154. Small Craft Advisory from 3 AM to 1 PM EDT Tuesday for AMZ156- 158. && $$ SYNOPSIS...RF NEAR TERM...RF/JBM/BM SHORT TERM...RF LONG TERM...HSA AVIATION...RF/HSA/BM MARINE...RF/JBM/HSA/BM
Area Forecast Discussion
National Weather Service Marquette MI
715 PM EDT Mon Oct 24 2016 .SHORT TERM...(This evening through Tuesday) Issued at 404 PM EDT MON OCT 24 2016 WV imagery and RAP analysis indicated nw mid/upper level flow through the nrn Great Lakes between a trough from ern Canada into New England and a ridge from the srn plains into Saskatchewan. At the surface, a ridge extended from Manitoba into the Upper MS valley resulting in anticyclonic nw flow into Upper Michigan. Although 850 mb temps around -6C (water temps near 11C) provided enough instability for isolated lake effect rain showers over the east, with daytime warming and an influx of drier air, the pcpn has diminished this afternoon. Tonight: As high pressure continued to build into the region, veering winds to the nne and 850 mb temps remaining near -6C will push the lake effect westward toward n cntrl Upper Michigan. Inversion heights near 4k-5k ft and continue acyc flow will limit intensity. Wet-bulb zero heights suggest pcpn will remain mainly as rain. Otherwise, mostly clear skies inland west will allow temps to fall into the upper 20s. Temperatures in the lower 30s are expected over the rest of the cwa. Tuesday: Confluent mid upper level flow, high pressure building over the region with low level dry air, and inversion heights lower to near 3k ft will bring an end to the lake effect pcpn by afternoon. However, the 925-850 mb thermal trough will remain close enough to support extensive stratocu development keeping highs in the mid 40s north and upper 40s south. .LONG TERM...(Tuesday night through Monday) Issued at 432 PM EDT MON OCT 24 2016 Surface ridge will slowly lift northeast away from the Great Lakes, allowing flow to turn easterly by late Tue night. Guidance continues to prog a shallow channel of moisture lingering overhead Tue ngt into Wed, but feel this is likely overdone and could end up with less shallow cloud cover Tue ngt. Upstream weak diffluent flow across the upper midwest will slow the arrival of a mid-lvl shortwave from pushing into the Dakotas until early Wed. This should all point towards precip not arriving over the Western Upper Pensinula until after midnight, and that too could be slower due to a weak downstream mid-lvl ridge over eastern Quebec. Wed morning the diffluent flow will begin to weaken, allowing the surface wave to strengthen across Iowa and produce a much tighter pressure gradient along the lee-side lifting north from Wisconsin towards Upper Peninsula. But the challenge will be on timing of cloud cover which could dampen the mixing of higher winds to the surface Wed. Profile will be moistening more Wed morning, with thermal profiles showing considerable cool air within the column and could support light snow mixing with rain. Accumulations should be difficult given the warm surface conditions; however, could see some minor slushy mix on grassy surfaces along the eastern forecast area with temps struggling to warm from the mid/upr 30s to lower 40s. The shortwave will be slow to push through the forecast area Wed ngt, and with a downstream weak ridge in place, this could result in a longer duration of a rain/snow mixture early Thur before the profile should warm enough to push it over to all liquid p-type. Current thinking is that temps will be cooler for Thur highs, and could see the lower 40s trending into the upper 30s away from the marine environment. The trough axis will then push east Thur ngt/Fri, with ridging returning to the upper midwest and eventually the Northern Great Lakes Fri. This may only be short-lived as operational guidance is indicating the Pac-NW system will be lifting north through the Canadian Rockies and arriving over the Upper Midwest/Great Lakes late Fri/early Sat. In between the mid-week system and weekend system, temps could rebound into the lower 50s before turning colder and into the low/mid 40s. Confidence in the extended periods for Sat/Sun is low at this time, given the spread amongst ensemble forecasts. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 715 PM EDT MON OCT 24 2016 Lake clouds will move back into SAW late tonight as winds shift from NW to N-NE over Lake Superior and cause conditions to drop to MVFR there. VFR conditions are expected elsewhere. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 406 PM EDT MON OCT 24 2016 Winds will remain below gales through the period. A tightening gradient between a deep low pressure system moving through Quebec and a high pressure ridge building into the Plains will lead to NW winds gusting to 30 knots over eastern Lake Superior into this evening. High pressure will then build across the area overnight into Tuesday, keeping winds generally light across Lake Superior. Southeast winds will increase again to 20 to 30 knots Wednesday into Wednesday evening as a low pressure system passing just south of the area. There will be a trough passage on Thursday but winds should still remain fairly light. Friday will see south winds increase to 20 to 30 knots again over the east half of Lake Superior as another low pressure system approaches from the Northern Plains. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...Beachler AVIATION...07 MARINE...JLB
Area Forecast Discussion
National Weather Service Phoenix AZ
842 PM MST MON OCT 24 2016 .SYNOPSIS... A low pressure system northwest of the region continues to draw a considerable amount of subtropical moisture into the Desert Southwest. This will lead to a threat of isolated showers and thunderstorms through tonight. Drier and warmer conditions will return by the middle of the week. && .DISCUSSION... Short wave continued to move northeast and into both far southeast California and Arizona this evening. Good difluent signature, partly seen in IR imagery, and jet dynamics with front left quad of an upper jet moving into the western CWA. Moisture overall has been confined mainly to mid/upper levels and instability has been rather low - especially over south central AZ where MLCAPE has been below 200 j/kg per the SPC Mesonanalysis graphics. So, despite pretty good QG forcing with the short wave, we have not seen overly strong storms today and most that occurred were located over the far western AZ deserts and portions of SE California. Still, after the first wave of storms moved thru the lower CO river valley earlier this evening, another area of storms pushed into far SE California and ane VERY impressive storm formed just east of Niland to the north of the Imperial Valley. SVR issued for this one with reflectivity over 70dbz in the mid levels, strong mid level meso sig and reflectivity over 55dbz above to 32k feet. Expect the wave to move quickly east tonight and will keep a threat of showers or storms going well past midnight especially over south central AZ. Forecasts appear to be in decent shape for now, will make additional edits should time permit/storms decrease out west. .PREVIOUS DISCUSSION... Latest MRMS shows isolated showers and thunderstorms across northern Arizona struggling to backbuild southwestward into the deeper moisture (PWATs > 1.0 inch). Meanwhile, an anomalous jet streak (95th percentile) across the Baja Peninsula precedes a southern-stream short-wave trough further west in the Eastern Pacific. Mostly cloudy skies have persisted throughout the day across much of the Desert Southwest which has limited diabatic heating and subsequent instability. Conditions will become more favorable for precipitation to develop this afternoon and this evening as the low pressure system tracks eastward. Best chance for showers and even a thunderstorm will be later this afternoon and this evening across La Paz, northern Maricopa and southern Gila County where favorable upslope flow from the approaching jet and vorticity forced ascent ahead of the trough are maximized. Hi-res WRFs including the latest runs of the HRRR indicate that any rain that develops will be quite light. Low- reflectivity depiction in the models also suggests sprinkles are certainly possible as well. With instability lacking, the chance for a thunderstorm will be slim, however given the cooler temperatures aloft, negative LIs suggest the potential for an isolated in-cloud flash. && .PREVIOUS DISCUSSION... Much drier air aloft will overtake the region from west to east starting late this evening as the jet max shifts into New Mexico. Low level moisture will remain over most of Arizona into Tuesday which may give rise to a few showers or maybe a thunderstorm over the higher terrain of east-central Arizona. Flow aloft turns out of the northwest as upper level ridging pushes northward out of Mexico. 500mb heights rebound quickly with 585dm heights already over the area by Tuesday afternoon. This will lead to another warming trend for the middle of this week. Highs may approach record levels in some areas with readings likely topping out into the 90-95 degree range starting Wednesday. This upper level ridge will get displaced slightly to the east late Thursday into Friday as a strong upper level low moves east northeastward toward the central California coast. Much of the moisture with this system will remain over California with only slight chances of showers over southeast California. The displaced upper level ridge is forecast to remain just to our east through the coming weekend keeping temperatures well above normal with little to no chance of any rain. && .AVIATION...South-Central Arizona including KPHX, KIWA, and KSDL: Southeast California/Southwest Arizona including KIPL and KBLH: Aviation discussion not updated for amended TAFs. && .FIRE WEATHER... Thursday through Monday... High pressure redeveloping over the Desert Southwest will bring dry conditions and well-above normal temperatures to the region on Thursday. Another weather system brushes the Desert Southwest from Friday into early Saturday for an increase in humidities and a slight chance of showers over SE CA. Warmer and drier weather is expected to return for next Sunday. Yet another pacific weather system brushing by to the west and north will bring cooler temperatures and an increase in winds/humidities from Sunday night into next Monday. Minimum humidities to remain mainly in the 15 to 25 percent range through the entire period, with overnight recoveries in the good range. && .SPOTTER INFORMATION STATEMENT... Spotters should follow standard reporting procedures. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ Visit us on Facebook...Twitter...and at weather.gov/phoenix DISCUSSION...CB PREVIOUS DISCUSSION...Hirsch/Kuhlman AVIATION...Percha FIRE WEATHER...Percha !--not sent--!
Area Forecast Discussion
National Weather Service Charleston WV
1122 PM EDT Mon Oct 24 2016 .SYNOPSIS... High pressure through Tuesday moves away Wednesday. Strong cold front crosses Thursday, and another Saturday. && .NEAR TERM /THROUGH TUESDAY/... As 0f 1030 PM Monday... No changes at this time, although conundrum is how expansive stratocu might get in and near the northern mountains of WV overnight, and its implications on the temperature, fog and frost forecast. If it were to clear / stay clear, then frost would become an issue farther east than currently advised. As of 745 PM Monday... Stratocu has dissipated and, while some may reform over northeast WV overnight, added valley fog there. May also need to lower temperatures and introduce frost there. Forecast is otherwise on track. As of 130 PM Monday... Post frontal stratocu in abundance across the area as CAA aloft commences. It will be a chilly night tonight and with high pressure trying to nose in from the northwest, frost possibilities arise. However, as if often the case around these parts, nothing is never clear cut. There is considerable concern for stratocu to linger across the northern WV mountains and adjacent lowland counties overnight in northwest flow. This is backed up by various model soundings including HRRR low level profile. Experience warrants this concern and thus frost may be mitigated across aforementioned locations. Further to the south and west, this should not be much of a concern so that areas of frost are likely across portions of southeast OH and central WV with patchy frost across the cold spots in northeast KY and elsewhere. After coordination with surrounding offices, elected to hoist a frost advisory for most of southeast OH and extending east into central WV, while leaving out the mountains for the above reasoning. Tuesday is shaping up to be a stellar Autumn day with just some passing high clouds as temps run a little below normal for this time of year, mainly across the north. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 400 PM AM Monday... A high pressure system will give way to a warm front Tuesday night. Timing of the clouds and winds with this boundary could be critical in regards to frost occurring. Based on current models, best chances of frost will be in the northern and eastern WV counties. Next rain producer arrives as a strong cold front on Thursday. Models in fairly decent agreement, so expect only minor timing changes. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 400 PM Monday... Good cold air advection behind Thursday`s cold front could provide some lingering light precipitation or drizzle into Friday. Yet another front could arrive on Saturday, with precipitation or drizzle once again possibly lingering into Sunday. Confidence in the timing of this system is significantly lower compared to Thursday. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... As of 745 PM Monday... High pressure will bring about mainly VFR conditions this period. Valley fog will form overnight but should remain shallow enough to not impact the runways. The exception is the Tygart Valley. Added IFR in fog there toward dawn. Not much if any cumulus is expected Tuesday, so just cirrus and some high altocumulus will embellish the sky. Northwest surface winds quickly subside this evening, yielding calm to light and variable flow, mainly northwest, veering to northeast on Tuesday. Moderate northwest flow aloft will subside somewhat overnight, and be light northwest on Tuesday. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE: Medium to high overnight, and then high on Tuesday. ALTERNATE SCENARIOS: Dense fog is possible at KEKN, and MVFR mist may form at other sites except BKW. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. Missing. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE TUE 10/25/16 UTC 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14 EDT 1HRLY 23 00 01 02 03 04 05 06 07 08 09 10 CRW CONSISTENCY H H H H H H H M L L L M HTS CONSISTENCY H H H H H H H H H M M M BKW CONSISTENCY H H H H H H H H H M M M EKN CONSISTENCY H H H H H H M M M L L M PKB CONSISTENCY H H H H H H H H M L L M CKB CONSISTENCY H H H H H H H H H M M M AFTER 06Z WEDNESDAY... IFR in valley fog possible Wednesday morning. Brief IFR possible in showers Thursday. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...Frost Advisory from 3 AM to 9 AM EDT Tuesday for WVZ008>011- 016>020-027>029. OH...Frost Advisory from 3 AM to 9 AM EDT Tuesday for OHZ066-067- 075-076-084-085. KY...None. VA...None. && $$ SYNOPSIS...TRM/RPY/30 NEAR TERM...TRM/30 SHORT TERM...RPY LONG TERM...RPY AVIATION...TRM
Area Forecast Discussion
National Weather Service Taunton MA
545 AM EDT Tue Oct 25 2016 .SYNOPSIS... West to northwest winds will continue to bring unseasonably cool but dry conditions across the region through midweek. Some of the coldest air of the season will push across the region Wednesday into Thursday. Low pressure will track across the region Thu into early Friday will bring a cold rain...possibly heavy at times and gusty winds along the coast. A period of snow and sleet is likely at the onset across the interior. A drying trend develops Fri in the wake of the low, but blustery northwest winds will develop. Another round of showers is possible sometime over the weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Low pressure at the surface and aloft continues to spin across the Maritimes with W-NW flow in place. Strong H85 cold air advection in place on the NW flow aloft, with temps falling back to -5C to -8C through midday before leveling off. Also noting an H85 jet of 30-35 kt to pass across the region by mid-late morning. Lapse rates will increase up to 10C/km through H85, will see low level mixing increase. This will bring gusts up to 25-30 mph, though may be higher across the higher inland terrain. Will still see good downsloping on the NW flow, so expect skies to be mostly sunny, though clouds may linger across the east slopes of the Berkshires as well as near the Mass/NH border through late morning. Some diurnal clouds may develop away from the coast. As the low across the Maritimes start to slowly shift E this afternoon, winds will diminish from W-E, though will remain gusty across Cape Cod and the islands. The winds will also slowly veer to a more northerly direction toward sunset, which will allow for low clouds to form across the warmer ocean waters near and east of Cape Cod. Some question as to whether some ocean effect showers may develop toward sunset as well. RAP and 4km NAM Bufkit soundings signaling some ocean effect precip may develop on the outer Cape. The big question will be whether the winds shift to a more northerly direction to allow the ocean effect precip to work in, or if it remains more NW and keep it offshore. With the excellent cold air advection in place, will be a very chilly day today. Expect highs only in the lower-mid 40s across the higher inland terrain, ranging to around 50 along the coast. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Tonight... N-NW winds will drop off, but not completely diminish except possibly the low inland valleys tonight. However, with the cold air in place, temperatures will plummet. Expect temps to fall below freezing away from the coast, but should hold in the upper 30s to mid 40s along the immediate coast. Some of our inland areas have not experienced a killing freeze yet, but should tonight. Have issued freeze warnings for those areas. Another question for tonight will be whether frost will form. Noting relative humidities up to 75 to around 90 percent after midnight in the areas where the freeze will take place. Can not rule out some patchy frost, especially where the winds drop off after midnight. Will also ocean effect clouds across portions of Cape Cod as well as Nantucket. There will also be a low chance for some showers there. Have only carried slight chance POPs mainly for the outer Cape and Nantucket. Wednesday... Any leftover clouds and isolated showers across the outer Cape should end by mid morning, though clouds will linger there through most if not the remainder of the day. Otherwise, high pressure will slowly push into the region, allowing for lighter N-NW winds. Skies will average out mostly sunny, though high clouds will filter in from the W during the afternoon. It will remain chilly though with highs in the 40s to around 50, mildest along the immediate south coast. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... Updated at 423 am... Highlights... * Coldest temperatures of the season possible Wed ngt/Thu morning * Cold rain and wind Thu/Thu ngt w/snow and sleet likely at the onset across the interior * Blustery with a drying trend Fri Wednesday Night... 1034 mb high over Quebec will nose southward into New England providing one of the colder nights this season. 850 temp anomalies are about -2 standard deviations colder than climo by days end Wed. This cold/dry airmass will combine with light winds and mostly clear skies to allow temps to plummet with sunset Wed evening. Northerly flow over Cape Cod and the islands will preclude temps from free falling given SSTs still in the upper 50s to low 60s. In addition this air/sea temp difference on northerly flow will likely yield ocean effect clouds and limit temps from being as cold as across the interior. Any ocean effect showers on Wed will diminish as subsidence inversion lowers Wed night with surface high cresting over New England. Also some uncertainty on exact timing of mid/high clouds arriving into western portions of CT/MA. This will impact temp forecast. Otherwise just a cold/dry night with diminishing winds. As for mins...used a blend of the colder MOS guidance to derive low temps. Thursday into Friday... Interesting setup with cold airmass lingering over the region early Thu in response to 1035 mb high over Quebec. Meanwhile Robust northern stream short wave energy diving southeast into the Great Lakes/OH valley. Differences in deterministic guidance with 00z EC colder than 00z GFS on the front end with airmass over the region early Thu. This results in the EC driving the baroclinic zone/storm track farther southward. In addition EC is stronger with jet energy diving into the Great Lakes/OH valley and also mergers energy quicker than GFS...although not as robust as its prior 12z run. This results in mid level flow digging farther southward to our latitude...which would delay warming in the mid levels. In addition this also results in cyclogenesis developing farther south than the GFS...with EC forming secondary low along the south coast. This scenario would linger low level cold air longer across the interior. Both GEFS and EPS ensembles provide support for the deeper/colder solution of the ECMWF. Thus will blend the stronger/colder ECMWF solution into this forecast. However not expecting a high impact event here given system is progressive and doesn/t really intensify until it moves northeast of the region into coastal ME and Gulf of ME. So for now expecting a period of snow and sleet Thu at the onset across northwest CT/MA...possibly as far east as the Worcester Hills with a risk of a minor accumulation across the higher terrain of the East slopes of the Berkshires. Otherwise...with mid level low tracking west-northwest of the region mid level warming overspreads the entire region with a changeover to all rain by late in the day. For the remainder of the region a cold rain is expected and possibly heavy at times given strong jet dynamics and moisture advection. Could also have a period of brief strong onshore winds Thu ngt across Coastal eastern MA as secondary low intensifies over RI/southeast MA before exiting into Gulf of ME. System is fairly progressive so should see a drying trend Fri along with brisk northwest winds on the backside of the low. Weekend... Models differ on next bundle of northern stream energy. Good agreement that there will be a period of showers sometime this weekend. GFS is of lower amplitude with progressive system and risk of showers late Sat into Sat night. ECMWF more dynamic with risk of showers Sat night thru Sun night. Early next week...uncertainty on timing of departing system Sun/Mon. However thereafter both deterministic and ensemble guid suggest pattern deamplifying next week...suggesting not as cold as this week. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Wednesday/...High confidence. Today...VFR. Mainly FEW-SCT clouds at 5-7kft across NE Mass and outer Cape Cod through midday. W-NW winds gusting up to 20-25 kts across higher terrain and coastal terminals. Tonight and Wednesday...Mainly VFR. May see MVFR CIGS move into outer Cape Cod and Nantucket with N-NW winds around or after 00Z through 14Z-15Z. Low risk of isolated showers. KBOS TAF...High confidence in TAF. KBDL TAF...High confidence in TAF. Outlook /Wednesday Night through Saturday/...Moderate confidence. Updated 423 am... Wednesday night... VFR and diminishing north winds. Thursday into Friday... IFR-LIFR likely. Initial SN/IP possible with potential accompanying LLWS transitioning to -RA/RA with embedded +RA, possible TSRA mostly S/SE. Blustery S/SE winds. Gusts up to 30 kts along the immediate shoreline terminals. Improving Friday with winds turning out of the WNW. Saturday... Brief period of VFR before conditions return low-end VFR to MVFR with another chance of -RA/RA. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Wednesday/...High confidence. NW winds will continue to gust up to 25-30 kt today, then gradually diminish tonight. Seas will remain up to 5-8 ft. Small craft advisories remain in effect. Winds and seas will diminish below small craft criteria along the near shore waters tonight, but will linger on the outer waters into Wednesday. Outlook /Wednesday Night through Saturday/...Moderate confidence. Wednesday night... North winds diminishing. Vsby may lower in rain and snow showers offshore. Thursday into Friday... Rain on the increase through Thursday, moderate to heavy at times with the possibility of thunderstorms. S/SE winds strengthening ahead of a deepening area of low pressure across the region. Seas building 8 to 10 feet the height of which will be on Friday, slowly dropping off thereafter as winds turn out of the W behind a cold front but remain breezy. Saturday... Breezy W winds continue as there is a brief lull in the weather. Seas remain above 5 feet on a good chunk of the waters as winds increase once again along with wet-weather late Saturday into Saturday night. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...Freeze Warning from 2 AM to 9 AM EDT Wednesday for CTZ003. MA...Freeze Warning from 2 AM to 9 AM EDT Wednesday for MAZ006-007- 013-014-018. RI...Freeze Warning from 2 AM to 9 AM EDT Wednesday for RIZ001-003- 006. MARINE...Small Craft Advisory until 2 AM EDT Wednesday for ANZ232. Small Craft Advisory until 8 PM EDT this evening for ANZ230- 233-234-236. Small Craft Advisory until noon EDT Wednesday for ANZ231. Small Craft Advisory until 1 AM EDT Wednesday for ANZ237. Small Craft Advisory until 9 AM EDT Wednesday for ANZ235. Small Craft Advisory until 6 PM EDT Wednesday for ANZ250-254- 255. Small Craft Advisory until 8 AM EDT Wednesday for ANZ251. Small Craft Advisory until 2 PM EDT Wednesday for ANZ256. && $$ SYNOPSIS...Nocera/EVT NEAR TERM...EVT SHORT TERM...EVT LONG TERM...Nocera AVIATION...Nocera/EVT MARINE...Nocera/EVT
Area Forecast Discussion
National Weather Service Caribou ME
427 AM EDT Tue Oct 25 2016 .SYNOPSIS... Low pressure northeast of the area will slowly move east toward the open Atlantic through Wednesday. Canadian high pressure will then cross the region Thursday. Low Pressure from the midwest will approach Thursday night...cross the Downeast coast by late Friday... then exit across the Maritimes Saturday. && .NEAR TERM /THROUGH TONIGHT/... An area of sn shwrs is slowly movg ESE out of NE ME into N Cntrl NB prov very erly this morn with a mid lvl vort max. Most near term models indicate isold to sct sn shwr cvrg for msly Nrn ptns of the FA for the remainder of the morn before another mid lvl vort max swinging Swrd from Ern QB potentially brings more numerous rn/sn shwrs this aftn across the NE, where we increase PoPs to the likely range. Fcst hrly sim radar ref from latest hrly HRRR model runs back this scenario. Despite sig abv fzg temps xpctd this aftn, heavier shwrs could result in enough cooling for lgt brief accumulation. Otherwise, sct shwrs will become all sn this eve as sfc-BL temps cool closer to fzg. Based on projected aftn 925-850mb temps being about a deg C less than ystdy aftn, fcst aftn hi temps across the FA should be at least 2 deg F than ystdy, and perhaps even a little cooler if cld cvr prevents much in the way of any brief sunshine. This same difference in 925-850 mb temps will likely result in ovrngt lows of a couple deg F cooler than this current erly AM. Winds will be brisk again tdy as they turn from the NW, but not quite as strong as ystdy, with winds diminishing to less than 10 mph tngt. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... A cold upper trough remains in place on Wednesday with snow showers continuing. An inverted trough will extend over the state from a low well east of Nova Scotia. An unstable layer up towards H700 will be in place to enable the snow showers. Boundary layer temps lead to a northward movement of the rain/snow line during the day, but the air aloft is sufficiently cold to maintain snow showers all day in northern zones. Will have to keep a close eye on whether the inverted trough becomes more focused on a particular region as such a development could produce heavier snow showers. The upper trough finally pulls out Wednesday night with snow showers ending. Cold high pressure builds from northern Quebec and should set up conditions for the coldest night of the season. Have gone with widespread readings in the teens for northern zones and mostly mid 20s for Bangor and the Down East region. The high will generate sunshine for Thursday with highs just short of 40F in the Saint John Valley and mid 40s for Bangor and Ellsworth. Clouds increase late Thursday in advance of the season`s first winter storm. Low pressure will track from the Western Great Lakes region and redevelop by late night in the Gulf of Maine. An upper level trough associated with the low will develop a negative tilt and the surface low will deepen by late Friday night. As always with early season winter storms, boundary layer temperatures and elevation will be key issues. As this point, it appears that a pretty strong onshore ESE flow will ensure boundary layer warmth for Bangor and all of the Down East region. The troubles could start as far south as a line from Dexter towards southern Aroostook County. It`s conceivable that 2-3 inches of snow could fall towards Dover-Foxcroft, Greenville and Millinocket by daybreak Friday. && .LONG TERM /FRIDAY THROUGH MONDAY/... The upper low will cut off over Maine and the surface low will continue to deepen Friday as it moves across the Gulf of Maine towards the Bay of Fundy. The surface track will minimize warm air advection northward. The upper low will promote instability aloft and bring good potential for heavier precip rates. This means that boundary layer issues often associated with these early season storms could be negated and snow could remain the dominant P-type. As a result, have made significant adjustments to the previous forecast in keeping snow in northern zones all day. Elevation will remain a big factor and the heaviest snows would likely be in the Katahdin region and higher terrain in Piscataquis County. Warning level snows are possible. Used ECMWF surface temps in the grids as other guidance looked too warm. The snow will gradually wind down Friday night as the upper low moves east of the state and the heavier precip rates end. This means a transition back towards rain with temperatures in the mid to upper 30s. There will be no real cold air advection behind this low. Generally warmer temperatures and cloudy conditions will follow Saturday into Monday. Temperatures will be in the 30s at night and in the upper 40s to near 50F during the day...which will melt the snow. There is another shortwave that will cross the area but timing is very uncertain with solutions ranging from Saturday night to Monday. The one certainty is that this system will be rain. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... NEAR TERM: Msly MVFR clgs and vsbys with intermittent sn and rn shwrs tdy and msly sn shwrs tngt can be xpctd across Nrn TAF sites with brief IFR clgs/vsbys possible with heavier sn shwrs. Otherwise low VFR clgs for Downeast sites, with brief MVFR clgs possible attms. SHORT TERM: MVFR cigs with tempo IFR conditions in snow showers will prevail Wednesday morning. Conditions will lift to VFR in the afternoon and persist until Thursday night when the trend will be towards IFR cigs for all sites...and LIFR/VLIFR vis in snow north of a line from GNR to HUL. This will continue all of Friday and into Friday night. LLWS is possible. Conditions will improve Saturday to a prevailing condition of MVFR cigs. && .MARINE... NEAR TERM: Will cont the SCA ovr our outer MZs tdy and tngt msly due to winds, but also marginal wv hts with cont`d llvl cold advcn NW winds. Primary wv pds will be msly in the 5 to 6 sec range, typical of short fetch off-shore wind directions. Kept close to WW3 wv guidance for fcst wv hts for this ptn of the fcst. SHORT TERM: SCA conditions may still exist early Wednesday morning, but winds and seas will quickly diminish during the morning. The next big event will be the potential for the season`s second gale event beginning Thursday night and going into Friday night. SCA conditions will follow the gale and last into Saturday evening. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...Small Craft Advisory until 4 AM EDT Wednesday for ANZ050-051. && $$ Near Term...VJN Short Term...MCW Long Term...MCW Aviation...VJN/MCW Marine...VJN/MCW
Area Forecast Discussion
National Weather Service El Paso TX/Santa Teresa NM
346 AM MDT Tue Oct 25 2016 .SYNOPSIS... A disturbance aloft has brought clouds to the Borderland this morning. A few showers are possible, mainly over the mountains. The disturbance moves east of the area late this afternoon, allowing the skies to clear. High pressure aloft then builds into the area Wednesday and will persist for most of the remainder of the week. This will allow clear skies and unseasonably warm temperatures to continue through the weekend. && .DISCUSSION... West flow aloft continues over the top of high pressure centered over the southern Baja Peninsula. A short wave in this flow continues toward New Mexico this morning and is now over eastern Arizona. Ample higher level moisture has allowed extensive mid and high level cloud decks over the CWA. Increasing PVA will produce lift over the area this morning, so slight chance of showers still looks reasonable for the Gila Region. By this afternoon the trough is over the Sacs and combined with some weakly unstable air, a thunderstorm is possible. NAM is bullish on this idea, and HRRR hints at the possibility so went ahead and included afternoon POPs for the Sacs. Otherwise aforementioned high pressure expands and builds north over much of the Desert Southwest through Thursday. Back to clear skies and warm temperatures. Temperatures may be hindered a degree or two today because of clouds, and a wind shift to the east on Wednesday, but then highs Thursday into the weekend will approach records, mainly because the records are lower. A series of short waves finally nudge the high pressure eastward some Friday and Saturday. Both GFS and ECMWF show band of higher clouds drifting over the area Friday/Saturday period, but not much else. && .AVIATION...Valid 25/12Z-26/12Z... VFR conds expected through the period with widespread P6SM SCT/BKN150 BKN/OVC300. These clouds will mostly move off to the east by late afternoon. Over the Gila Wilderness this morning slgt chc -SHRA BKN100 through about 19Z. Over the Sacramento Mts after 18Z slgt chc -SHRA/TSRA with BKN090CB til 23Z. && .FIRE WEATHER... An upper level disturbance will bring a slight chance of showers or thunderstorms to the area through this afternoon, mainly over the mountain zones. Otherwise, an upper ridge will start to rebuild over the region with near record highs continuing into the weekend. Min RHs will range from about 20-35% each day, highest in the mountains. No significant winds are expected. && .PRELIMINARY POINT TEMPS/POPS... El Paso 86 58 87 57 / 0 0 0 0 Sierra Blanca 82 53 84 53 / 0 0 0 0 Las Cruces 84 52 85 52 / 0 0 0 0 Alamogordo 83 52 85 52 / 0 0 0 0 Cloudcroft 66 38 67 36 / 10 0 0 0 Truth or Consequences 82 50 83 52 / 0 0 0 0 Silver City 76 47 77 48 / 10 0 0 0 Deming 84 50 85 50 / 0 0 0 0 Lordsburg 83 49 85 50 / 0 0 0 0 West El Paso Metro 85 59 85 58 / 0 0 0 0 Dell City 87 52 87 49 / 0 0 0 0 Fort Hancock 88 57 89 55 / 0 0 0 0 Loma Linda 79 54 79 56 / 0 0 0 0 Fabens 87 56 87 55 / 0 0 0 0 Santa Teresa 85 54 86 54 / 0 0 0 0 White Sands HQ 84 56 85 56 / 0 0 0 0 Jornada Range 83 42 84 46 / 0 0 0 0 Hatch 83 46 84 51 / 0 0 0 0 Columbus 85 53 86 52 / 0 0 0 0 Orogrande 84 54 85 54 / 0 0 0 0 Mayhill 74 45 74 43 / 10 0 0 0 Mescalero 74 43 74 41 / 10 0 0 0 Timberon 73 42 71 41 / 10 0 0 0 Winston 76 42 77 43 / 10 0 0 0 Hillsboro 81 43 82 42 / 10 0 0 0 Spaceport 81 44 82 47 / 0 0 0 0 Lake Roberts 77 39 78 40 / 10 0 0 0 Hurley 77 44 80 45 / 10 0 0 0 Cliff 81 36 82 36 / 0 0 0 0 Mule Creek 78 34 80 35 / 0 0 0 0 Faywood 81 43 82 44 / 10 0 0 0 Animas 84 49 87 48 / 0 0 0 0 Hachita 83 48 85 47 / 0 0 0 0 Antelope Wells 83 49 86 48 / 0 0 0 0 Cloverdale 78 50 81 53 / 0 0 0 0 && .EPZ WATCHES/WARNINGS/ADVISORIES... NM...None. TX...None. && $$ 17 Hefner
Area Forecast Discussion
National Weather Service Fort Worth TX
225 AM CDT Tue Oct 25 2016 .DISCUSSION... A light wind and a mostly clear sky will result in some patchy fog across the eastern and southern portions of the forecast area early this morning. A few spots could see visibilities reduced to around 1 mile, but wind speeds should stay up just enough to prevent widespread dense fog from forming. Any fog that does develop will dissipate by mid morning and give way to a mostly sunny sky. Pacific moisture will increase from west to east today as an upper level low rotates across the West Coast. The main energy will remain just offshore the next several days but some short waves will branch off and translate east across the CONUS. The first wave which is currently across the Desert Southwest will move into the Central Plains tonight and allow a weak cold front to move south. The cold front is progged by nearly all models to remain north of the Red River. However, the GFS does bring some showers and storms to the northeast quarter of North Texas Wednesday night. For now we feel this solution is too aggressive since nearly all large scale forcing for ascent will be displaced well to the north and meso-scale lift along the front will also remain north. Therefore, we will not introduce any pops into the forecast for the Wednesday/Wednesday night time frame. Upper level high pressure will build in from the west behind the mid week short wave and remain in place through the weekend. Another short wave will translate across the Central Plains late Friday through Saturday but this feature should have little if any direct influence on the weather across North and Central Texas with the exception of keeping a constant influx of low level moisture due to surface lee troughing. The weather pattern will not change much to start the first week of November with southwest flow aloft and a persistent feed of Gulf moisture. Temperatures through early next week will be fairly consistent with highs in the lower and middle 80s and lows in the lower and middle 60s. 79 && .AVIATION... /ISSUED 1202 AM CDT Tue Oct 25 2016/ 06 UTC TAF Cycle Concerns---VFR for the DFW Metroplex. MVFR visibility and ceiling potential at Waco Tuesday morning. For the Metroplex TAF sites---VFR is expected to prevail through a bulk of the 06 UTC TAF cycle. Low level flow appears as if it will be too weak to support transport of any MVFR stratus this far northward during the overnight hours. High clouds will invade from the northwest ahead of a potent longwave trough across the western portion of the U.S. Diurnal VFR CU along with mid/upper level clouds will build through the day ahead of this feature. There appears to be a signal from some model guidance that there may be the potential for some MVFR stratus at the tail end of the 30 hour DFW TAF. Low confidence in the timing of the MVFR stratus, however, warrants keeping the TAFs VFR for now. For the Waco TAF site---A slightly tricker TAF here as there has been some signal in the model guidance for restricted ceilings and visibility. A couple of ingredients are already in place that would facilitate fog development (clear skies though a few thin high clouds are possible and light winds). The somewhat unknown ingredient is sufficient low level moisture. Dewpoint depressions across central McLennan County have also fallen to around 3-6 degrees. More important to Waco Regional will be the slightly veering winds that are forecast to occur. If this occurs highly localized moisture advection across the airfield compliments of Lake Waco will occur, and could result in even poorer ceilings (IFR) than currently forecast. The latest consensus of high- resolution model output remains fairly aggressive with low visibilities per raw output and there appears to be a reflection of this in both NAM and RAP forecast profiles. Because of the uncertainty as to how reduced visibilities will fall (should fog occur), I`ll TEMPO MVFR visibility around 3SM from 11 UTC to 15 UTC. As this layer lifts, it`s likely that there will be some brief periods of near IFR to MVFR ceilings. Thereafter, diurnal VFR CU should develop in the afternoon. 24-Bain && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 65 84 64 85 65 / 5 5 10 0 0 Waco 62 85 61 86 61 / 5 5 5 0 0 Paris 59 82 60 84 61 / 5 10 10 5 0 Denton 62 84 61 84 62 / 5 5 10 0 0 McKinney 62 83 61 84 62 / 5 5 10 0 0 Dallas 65 84 65 85 65 / 5 5 10 0 0 Terrell 62 83 61 84 61 / 5 5 10 0 0 Corsicana 62 84 62 85 61 / 5 5 5 0 0 Temple 61 84 61 85 60 / 5 5 5 0 0 Mineral Wells 61 85 60 85 60 / 5 5 5 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 90/79
Area Forecast Discussion
National Weather Service Elko NV
246 AM PDT Tue Oct 25 2016 .SYNOPSIS...Isolated showers are possible across far northern Nevada this afternoon as another disturbance brushes the region. Dry and mild Wednesday and Thursday then more showers will move into the region Thursday night and Friday with a chance for significant rainfall. && .SHORT TERM...Today through Wednesday. Showers have ended over northeast Nevada early this morning as the short wave has moved downstream. Southwest flow aloft prevails today with another Pacific wave brushing northern Nevada. The higher resolution models do not show any precipitation in the lee of the Sierra and downstream across northern Nevada. There is sufficient moisture and low level weak instability for an isolated shower north of I80, the HRRR model may be too dry. However if any showers do develop, it will be brief and most likely miss any populated areas. Rising heights continue tonight and Wednesday. Once the Pacific wave brushes northern Nevada this afternoon, clearing skies are expected late in the day. Mostly sunny conditions are expected on Wednesday with warmer days. Valleys reaching the upper 60s to lower 70s will be common. .LONG TERM...Wednesday night through Tuesday. With the upper level pattern continuing to be progressive, several storms are poised to move through the Great Basin and yield some precipitation. The strength and moisture content is still hard to determine at this time do to variance from model to model. There is better agreement however between the models on the system before Monday so confidence in the long term forecast is improving. There is still large discrepancy on the storm system beyond Monday as different model solutions vary largely in timing and intensity. Another source of uncertainty will be caused by the the infusion of energy from dying tropical systems later in the week which the models are not currently handling well. Wednesday night through Thursday morning. High pressure centered over Mexico and the Baja Region will provide dry weather. Temperatures will be relatively mild as 582DM H5 heights expand northward into Idaho and Wyoming. Lows will generally be in the 40s. Thursday afternoon. A weak shortwave will move through the Pacific Northwest and brush Nevada. The passage of this wave will help pull up some Pacific moisture into Humboldt County primarily, but could affect parts of Lander and Nye Counties as well. High temperatures will be in the 60s. Thursday night to Friday night. A robust shortwave will move through California and Nevada with some remnant tropical moisture getting infused into the flow. With a good fetch of moisture, this system could produce a half-inch of rain for the valleys of northern Nevada as it crosses and re- develops lee-side of the Sierras. Low temperatures will be in the 40s. High temperatures will range from the mid 50s to the lower 60s. Saturday morning to afternoon. A fairly dry period with ample cloud cover in between storm systems. This period will see the previous moisture move eastward with a deepening system off the west coast. The moisture will gradually begin to intrude across the state. High temperature will be in the 50`s Saturday night through Sunday. A strong short wave trough is progged to pass over the state bringing ample moisture for another round of showers. There is a little model discrepancy on the exact intensity of this trough which may impact the coverage of the moisture and showers. High temperatures will range from the mid 50s to the lower 60s. Low temperatures will be in the 30s. Monday through Tuesday. A fair amount of model discrepancy is present after the passage of the strong short wave trough on Sunday. Both the EC and GFS agree that another short wave trough will form and move inland but they cannot agree on timing and intensity. The EC favors a far slower and deeper system while the GFS favors a weak rapid moving system. This produces great uncertainty with the moisture profile of the system and the impacts it will have on the state. High temperatures will be in the 50s. Low temperatures will be in the 30s. && .AVIATION...VFR conditions with generally light winds for all terminals for the next 24 hours. There will be the chance for some fog at KEKO this morning but the confidence is not high due to intruding drier air which may impede formation. && .FIRE WEATHER...Isolated showers will be confined to far northern NV. Dry all areas Wednesday and Thursday. Mild temperatures will continue with the warmer locales reaching the lower 70s on Wednesday and Thursday. Another storm system will bring showers Thursday night and Friday. && .LKN WATCHES/WARNINGS/ADVISORIES... None. && $$ 88/99/99/88
Area Forecast Discussion
National Weather Service Norman OK
320 AM CDT Tue Oct 25 2016 .DISCUSSION... High clouds will continue to increase today ahead of a fast moving shortwave trough. Being late October this should have some impact on insolation this afternoon. RAP and NAM soundings indicate the best opportunity for afternoon storms will be across southwest Oklahoma and western north Texas. Even this area will likely remain capped. This evening and overnight, showers and a few thunderstorms may develop, especially across north central Oklahoma. Will keep high chance POPs for this area. An associated front will enter northwest Oklahoma around sunrise Wednesday, while a few elevated showers move across north central and central Oklahoma. By mid to late afternoon, the frontal boundary will become nearly stationary north and west of Interstate 44. Capping will be an issue again, but an isolated storm or two may form ahead of front during peak heating (central and south central OK). After Wednesday, a mid and upper ridge centered over northern Mexico will build east into Texas and the Southern Plains. This will bring yet another period of dry weather with well above average temperatures. A weak front should push into far northern Oklahoma Saturday afternoon, but areas ahead of the front will warm into at least the mid and upper 80s. Near record high temperature are expected at least Friday and Saturday. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 78 62 81 57 / 0 30 30 10 Hobart OK 79 63 83 55 / 0 10 10 0 Wichita Falls TX 80 63 84 58 / 0 10 10 0 Gage OK 80 58 83 48 / 0 20 0 0 Ponca City OK 80 63 80 52 / 0 50 30 0 Durant OK 80 60 82 61 / 0 10 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ 11/06
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
322 AM CDT Tue Oct 25 2016 .SHORT TERM...(Today and tonight) Issued at 319 AM CDT Tue Oct 25 2016 A lead upper level trough ahead of a nearly stationary longer wave length upper trough off the western coast of the US will lift northeast across the plains Tonight. A lee surface low across western KS will deepen through the day and move northeast into south central NE by 00Z WED. A surface cold front will move from eastern CO, eastward across west central KS through the afternoon hours and into the western counties of the CWA by 02Z WED. Point forecast soundings from the 00Z NAM and WRF models show an EML at around 735MB overspreading the warm sector during the afternoon hours and through the evening hours as well. There may be enough ascent ahead of the weak upper trough and lift along the surface front for scattered thunderstorms to develop southwest along the surface front from southern NE across the central counties of the CWA after 3Z. The only model that shows deep moist convection developing after 00Z is the 00Z GFS model. The WRF solutions keep the CAP strong enough that only isolated storms develop after 9Z along the surface front along and southeast of the KS turnpike. The most favorable environment for strong to severe thunderstorms would be during the late afternoon and early evening hours where MLCAPES will increase to 1500-2000 J/KG with 0-6KM shear increasing to 25 to 30 KTS. However the cap may prevent storms from developing along the front. If surface based storms manage to break the cap, they may become severe with the potential for large hail and damaging wind gusts across north central KS. If the NAM, WRF and RAP solutions end up verifying then thunderstorms may not develop until near midnight across the eastern and southern half of the CWA. The MUCAPE will decrease to 1000-1500 J/KG but the 0-6KM shear will increase slightly to 30 to 40 KTS. Thus a strong or severe thunderstorms will still be possible. If deep moist convection does not develop until around 6Z the primary hazard with any strong to severe storm would be large hail, since the boundary layer may decouple enough to prevent severe wind gusts. Rainfall will depend on thunderstorm coverage and intensity. If storms develop along the front around 6z and last through the early morning hours, then some locations across east central KS may pick up a quarter to a half inch of rainfall. Highs this afternoon will reach the mid to upper 70s this afternoon as WAA at 850mb increases 850mb temperatures between 14 and 18 degree C. The boundary layer should mix to around 850mb and any stratus this morning should mix out during the late morning and early afternoon hours. South winds will increase to 15 to 25 MPH with higher gusts from the late morning hours through the afternoon and into the evening hours. .LONG TERM...(Wednesday through Monday) Issued at 319 AM CDT Tue Oct 25 2016 The mid range and extended forecast will be dominated by an upper ridge over the southern US resulting in mainly zonal flow over the region. A series of dry cold fronts will cause up and down temperatures. The first front passes through the area Friday night, therefore Friday appears to be the warmest day. High temperatures are forecasted to reach around 80, but only cool into the low to mid 70s over the weekend. Another front approaches the area on Monday so highs slightly increase only to drop into the 60s by Tuesday. A deepening trough over the western US will allow more shortwaves to track over the central plains, which will bring chances for showers and storms through mid week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday) Issued at 1154 PM CDT Mon Oct 24 2016 Models show a warm air advection pattern persisting overnight with decent isentropic upglide and moisture return. Although forecast soundings maintain some inhibition just above the lift. Because of this have not included any mention of precip and high res models suggest areas north of the terminals may be more likely for elevated showers. Forecast soundings also show a steep inversion developing, so LLWS is of some concern. Winds at the top of the inversion are progged to be from the south at 20 to 25 KT and profiler data have been verifying this. Will continue to monitor trends to see how strong the low level jet becomes overnight. Stratus with the low level warm air advection is coming in around 4 KFT so a VFR forecast looks on track. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Gargan LONG TERM...Sanders AVIATION...Wolters
Area Forecast Discussion
National Weather Service Bismarck ND
856 AM CDT Tue Oct 25 2016 .UPDATE... Issued at 841 AM CDT Tue Oct 25 2016 At 8 am CDT a warm frontal boundary extended from low pressure across western South Dakota through eastern Nebraska. During the day today a short wave trough will move from Wyoming through the northern plains. Deterministic models all show increasing chances for showers across south central and eastern North Dakota. Latest HRRR runs focus the accumulating rainfall east of the Missouri river with best chances in the James river valley as the southerly low level flow increases in response to the approaching short wave. current forecast looks good. UPDATE Issued at 631 AM CDT Tue Oct 25 2016 First round of very light showers continues to push east through south central North Dakota into the James River Valley. Expect this to continue to slide east with the broader are of precipitation developing later today. Previous forecast reflected this well so kept changes to a minimum. && .SHORT TERM...(Today and tonight) Issued at 338 AM CDT Tue Oct 25 2016 Chances of rain showers highlights the short term forecast. Currently...an upper level ridge was established over the northern plains with a shortwave impulse over Wyoming moving northeastward. A southeasterly level jet was also in place from the central plains northward through the Dakotas and into Saskatchewan. As the upper level shortwave approaches, we should see increasing low and mid level cloud layers forming and streaming north/northwestward across the region. The upper level shortwave is forecast to move northeast across SD and the southern ND, reaching MN late tonight. Plenty of moisture expected from the low level jet should bring some moderate rainfall to the James Valley, where chances of rain showers are likely - especially this afternoon and evening. There may be some very light isolated showers in western ND today, but the better chances are in the central - with the best chances farther east in the James Valley. Temperatures today are expected to be in the 50s in the west, but only reach into the 40s in the James Valley. .LONG TERM...(Wednesday through Monday) Issued at 338 AM CDT Tue Oct 25 2016 The main feature in the extended period will be a cold front moving through the state on Friday. The upper level ridge builds back up Wednesday/Thursday bringing dry weather and warmer conditions with highs in the 50s and 60s. Another shortwave riding the ridge will bring a cold front through the region Friday with gusty northwest winds of 20 to 30 mph and cooler conditions, with highs Friday in the 50s, but highs only in the 40s on Saturday. More upper level shortwave impulses following the cold front will bring a chance of rain or snow to mainly western ND Friday night and Saturday morning. Another upper level longwave trough arrives over the west coast Saturday/Sunday. Shortwave energy from this trough streams northeastward across the Rockies as the trough expands and begins moving east. This will bring another chance of rain to our area Monday, with a chance of rain/snow Monday night. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 631 AM CDT Tue Oct 25 2016 VFR conditions early this morning will gradually transition to MVFR after daybreak in stratus across much of western and central North Dakota. There is some uncertainty regarding whether the stratus will reach as far west as KISN or KDIK. In central ND ceilings will continue to lower into the afternoon, with IFR conditions possible in rain. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...JV LONG TERM...JV AVIATION...JJS
Area Forecast Discussion
National Weather Service Taunton MA
711 AM EDT Tue Oct 25 2016 .SYNOPSIS... West to northwest winds will continue to bring unseasonably cool but dry conditions across the region through midweek. Some of the coldest air of the season will push across the region Wednesday into Thursday. Low pressure will track across the region Thu into early Friday and will be accompanied by a cold rain...possibly heavy at times and gusty winds along the coast. A period of snow and sleet is likely at the onset across the interior. A drying trend develops Fri in the wake of the low, but blustery northwest winds develop. Another round of showers is possible sometime over the weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 7 am update... Not much change from previous forecast. Cold but dry NW flow continues across New England. SPC mesoanalysis indicates 850 temps currently -5C to -6C across the area at 7 am with -9C upstream just across the NY/VT Canadian border. Thus robust cold air advection for late Oct with 850 mb temps anomalies running around -2 standard deviations colder than climo. Winds will increase later this morning as solar heating increases blyr mixing. This will only exacerbate the chilly conditions. Expect a mix of sun and clouds in this flow regime. Previous discussion below. =================================================================== Low pressure at the surface and aloft continues to spin across the Maritimes with W-NW flow in place. Strong H85 cold air advection in place on the NW flow aloft, with temps falling back to -5C to -8C through midday before leveling off. Also noting an H85 jet of 30-35 kt to pass across the region by mid-late morning. Lapse rates will increase up to 10C/km through H85, will see low level mixing increase. This will bring gusts up to 25-30 mph, though may be higher across the higher inland terrain. Will still see good downsloping on the NW flow, so expect skies to be mostly sunny, though clouds may linger across the east slopes of the Berkshires as well as near the Mass/NH border through late morning. Some diurnal clouds may develop away from the coast. As the low across the Maritimes start to slowly shift E this afternoon, winds will diminish from W-E, though will remain gusty across Cape Cod and the islands. The winds will also slowly veer to a more northerly direction toward sunset, which will allow for low clouds to form across the warmer ocean waters near and east of Cape Cod. Some question as to whether some ocean effect showers may develop toward sunset as well. RAP and 4km NAM Bufkit soundings signaling some ocean effect precip may develop on the outer Cape. The big question will be whether the winds shift to a more northerly direction to allow the ocean effect precip to work in, or if it remains more NW and keep it offshore. With the excellent cold air advection in place, will be a very chilly day today. Expect highs only in the lower-mid 40s across the higher inland terrain, ranging to around 50 along the coast. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Tonight... N-NW winds will drop off, but not completely diminish except possibly the low inland valleys tonight. However, with the cold air in place, temperatures will plummet. Expect temps to fall below freezing away from the coast, but should hold in the upper 30s to mid 40s along the immediate coast. Some of our inland areas have not experienced a killing freeze yet, but should tonight. Have issued freeze warnings for those areas. Another question for tonight will be whether frost will form. Noting relative humidities up to 75 to around 90 percent after midnight in the areas where the freeze will take place. Can not rule out some patchy frost, especially where the winds drop off after midnight. Will also ocean effect clouds across portions of Cape Cod as well as Nantucket. There will also be a low chance for some showers there. Have only carried slight chance POPs mainly for the outer Cape and Nantucket. Wednesday... Any leftover clouds and isolated showers across the outer Cape should end by mid morning, though clouds will linger there through most if not the remainder of the day. Otherwise, high pressure will slowly push into the region, allowing for lighter N-NW winds. Skies will average out mostly sunny, though high clouds will filter in from the W during the afternoon. It will remain chilly though with highs in the 40s to around 50, mildest along the immediate south coast. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... Updated at 423 am... Highlights... * Coldest temperatures of the season possible Wed ngt/Thu morning * Cold rain and wind Thu/Thu ngt w/snow and sleet likely at the onset across the interior * Blustery with a drying trend Fri Wednesday Night... 1034 mb high over Quebec will nose southward into New England providing one of the colder nights this season. 850 temp anomalies are about -2 standard deviations colder than climo by days end Wed. This cold/dry airmass will combine with light winds and mostly clear skies to allow temps to plummet with sunset Wed evening. Northerly flow over Cape Cod and the islands will preclude temps from free falling given SSTs still in the upper 50s to low 60s. In addition this air/sea temp difference on northerly flow will likely yield ocean effect clouds and limit temps from being as cold as across the interior. Any ocean effect showers on Wed will diminish as subsidence inversion lowers Wed night with surface high cresting over New England. Also some uncertainty on exact timing of mid/high clouds arriving into western portions of CT/MA. This will impact temp forecast. Otherwise just a cold/dry night with diminishing winds. As for mins...used a blend of the colder MOS guidance to derive low temps. Thursday into Friday... Interesting setup with cold airmass lingering over the region early Thu in response to 1035 mb high over Quebec. Meanwhile Robust northern stream short wave energy diving southeast into the Great Lakes/OH valley. Differences in deterministic guidance with 00z EC colder than 00z GFS on the front end with airmass over the region early Thu. This results in the EC driving the baroclinic zone/storm track farther southward. In addition EC is stronger with jet energy diving into the Great Lakes/OH valley and also mergers energy quicker than GFS...although not as robust as its prior 12z run. This results in mid level flow digging farther southward to our latitude...which would delay warming in the mid levels. In addition this also results in cyclogenesis developing farther south than the GFS...with EC forming secondary low along the south coast. This scenario would linger low level cold air longer across the interior. Both GEFS and EPS ensembles provide support for the deeper/colder solution of the ECMWF. Thus will blend the stronger/colder ECMWF solution into this forecast. However not expecting a high impact event here given system is progressive and doesn/t really intensify until it moves northeast of the region into coastal ME and Gulf of ME. So for now expecting a period of snow and sleet Thu at the onset across northwest CT/MA...possibly as far east as the Worcester Hills with a risk of a minor accumulation across the higher terrain of the East slopes of the Berkshires. Otherwise...with mid level low tracking west-northwest of the region mid level warming overspreads the entire region with a changeover to all rain by late in the day. For the remainder of the region a cold rain is expected and possibly heavy at times given strong jet dynamics and moisture advection. Could also have a period of brief strong onshore winds Thu ngt across Coastal eastern MA as secondary low intensifies over RI/southeast MA before exiting into Gulf of ME. System is fairly progressive so should see a drying trend Fri along with brisk northwest winds on the backside of the low. Weekend... Models differ on next bundle of northern stream energy. Good agreement that there will be a period of showers sometime this weekend. GFS is of lower amplitude with progressive system and risk of showers late Sat into Sat night. ECMWF more dynamic with risk of showers Sat night thru Sun night. Early next week...uncertainty on timing of departing system Sun/Mon. However thereafter both deterministic and ensemble guid suggest pattern deamplifying next week...suggesting not as cold as this week. && .AVIATION /11Z TUESDAY THROUGH SATURDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Updated 7 am... Not much change from 06z and 09z TAFs. Any cigs will be in the VFR range. Main issue today will be gusty WNW winds from late morning into the afternoon. Earlier discussion below. ===================================================================== Short Term /through Wednesday/...High confidence. Today...VFR. Mainly FEW-SCT clouds at 5-7kft across NE Mass and outer Cape Cod through midday. W-NW winds gusting up to 20-25 kts across higher terrain and coastal terminals. Tonight and Wednesday...Mainly VFR. May see MVFR CIGS move into outer Cape Cod and Nantucket with N-NW winds around or after 00Z through 14Z-15Z. Low risk of isolated showers. KBOS TAF...High confidence in TAF. KBDL TAF...High confidence in TAF. Outlook /Wednesday Night through Saturday/...Moderate confidence. Updated 423 am... Wednesday night... VFR and diminishing north winds. Thursday into Friday... IFR-LIFR likely. Initial SN/IP possible with potential accompanying LLWS transitioning to -RA/RA with embedded +RA, possible TSRA mostly S/SE. Blustery S/SE winds. Gusts up to 30 kts along the immediate shoreline terminals. Improving Friday with winds turning out of the WNW. Saturday... Brief period of VFR before conditions return low-end VFR to MVFR with another chance of -RA/RA. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Wednesday/...High confidence. NW winds will continue to gust up to 25-30 kt today, then gradually diminish tonight. Seas will remain up to 5-8 ft. Small craft advisories remain in effect. Winds and seas will diminish below small craft criteria along the near shore waters tonight, but will linger on the outer waters into Wednesday. Outlook /Wednesday Night through Saturday/...Moderate confidence. Wednesday night... North winds diminishing. Vsby may lower in rain and snow showers offshore. Thursday into Friday... Rain on the increase through Thursday, moderate to heavy at times with the possibility of thunderstorms. S/SE winds strengthening ahead of a deepening area of low pressure across the region. Seas building 8 to 10 feet the height of which will be on Friday, slowly dropping off thereafter as winds turn out of the W behind a cold front but remain breezy. Saturday... Breezy W winds continue as there is a brief lull in the weather. Seas remain above 5 feet on a good chunk of the waters as winds increase once again along with wet-weather late Saturday into Saturday night. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...Freeze Warning from 2 AM to 9 AM EDT Wednesday for CTZ003. MA...Freeze Warning from 2 AM to 9 AM EDT Wednesday for MAZ006-007- 013-014-018. RI...Freeze Warning from 2 AM to 9 AM EDT Wednesday for RIZ001-003- 006. MARINE...Small Craft Advisory until 2 AM EDT Wednesday for ANZ232. Small Craft Advisory until 8 PM EDT this evening for ANZ230- 233-234-236. Small Craft Advisory until noon EDT Wednesday for ANZ231. Small Craft Advisory until 1 AM EDT Wednesday for ANZ237. Small Craft Advisory until 9 AM EDT Wednesday for ANZ235. Small Craft Advisory until 6 PM EDT Wednesday for ANZ250-254- 255. Small Craft Advisory until 8 AM EDT Wednesday for ANZ251. Small Craft Advisory until 2 PM EDT Wednesday for ANZ256. && $$ SYNOPSIS...Nocera/EVT NEAR TERM...Nocera/EVT SHORT TERM...EVT LONG TERM...Nocera AVIATION...Nocera/EVT MARINE...Nocera/EVT
Area Forecast Discussion
National Weather Service Caribou ME
1123 AM EDT Tue Oct 25 2016 .SYNOPSIS... Low pressure northeast of the area will slowly move east toward the open Atlantic through Wednesday. Canadian high pressure will then cross the region Thursday. Low Pressure from the midwest will approach Thursday night...cross the Downeast coast by late Friday... then exit across the Maritimes Saturday. && .NEAR TERM /THROUGH TONIGHT/... 11:20 AM Update...Increased cloud cover Downeast where clouds have filled in as moisture circulates south across the area. Also raised temps a couple degrees Downeast through the midday hours. Otherwise, no major changes this hour. Orgnl Disc: An area of sn shwrs is slowly movg ESE out of NE ME into N Cntrl NB prov very erly this morn with a mid lvl vort max. Most near term models indicate isold to sct sn shwr cvrg for msly Nrn ptns of the FA for the remainder of the morn before another mid lvl vort max swinging Swrd from Ern QB potentially brings more numerous rn/sn shwrs this aftn across the NE, where we increase PoPs to the likely range. Fcst hrly sim radar ref from latest hrly HRRR model runs back this scenario. Despite sig abv fzg temps xpctd this aftn, heavier shwrs could result in enough cooling for lgt brief accumulation. Otherwise, sct shwrs will become all sn this eve as sfc-BL temps cool closer to fzg. Based on projected aftn 925-850mb temps being about a deg C less than ystdy aftn, fcst aftn hi temps across the FA should be at least 2 deg F than ystdy, and perhaps even a little cooler if cld cvr prevents much in the way of any brief sunshine. This same difference in 925-850 mb temps will likely result in ovrngt lows of a couple deg F cooler than this current erly AM. Winds will be brisk again tdy as they turn from the NW, but not quite as strong as ystdy, with winds diminishing to less than 10 mph tngt. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... A cold upper trough remains in place on Wednesday with snow showers continuing. An inverted trough will extend over the state from a low well east of Nova Scotia. An unstable layer up towards H700 will be in place to enable the snow showers. Boundary layer temps lead to a northward movement of the rain/snow line during the day, but the air aloft is sufficiently cold to maintain snow showers all day in northern zones. Will have to keep a close eye on whether the inverted trough becomes more focused on a particular region as such a development could produce heavier snow showers. The upper trough finally pulls out Wednesday night with snow showers ending. Cold high pressure builds from northern Quebec and should set up conditions for the coldest night of the season. Have gone with widespread readings in the teens for northern zones and mostly mid 20s for Bangor and the Down East region. The high will generate sunshine for Thursday with highs just short of 40F in the Saint John Valley and mid 40s for Bangor and Ellsworth. Clouds increase late Thursday in advance of the season`s first winter storm. Low pressure will track from the Western Great Lakes region and redevelop by late night in the Gulf of Maine. An upper level trough associated with the low will develop a negative tilt and the surface low will deepen by late Friday night. As always with early season winter storms, boundary layer temperatures and elevation will be key issues. As this point, it appears that a pretty strong onshore ESE flow will ensure boundary layer warmth for Bangor and all of the Down East region. The troubles could start as far south as a line from Dexter towards southern Aroostook County. It`s conceivable that 2-3 inches of snow could fall towards Dover-Foxcroft, Greenville and Millinocket by daybreak Friday. && .LONG TERM /FRIDAY THROUGH MONDAY/... The upper low will cut off over Maine and the surface low will continue to deepen Friday as it moves across the Gulf of Maine towards the Bay of Fundy. The surface track will minimize warm air advection northward. The upper low will promote instability aloft and bring good potential for heavier precip rates. This means that boundary layer issues often associated with these early season storms could be negated and snow could remain the dominant P-type. As a result, have made significant adjustments to the previous forecast in keeping snow in northern zones all day. Elevation will remain a big factor and the heaviest snows would likely be in the Katahdin region and higher terrain in Piscataquis County. Warning level snows are possible. Used ECMWF surface temps in the grids as other guidance looked too warm. The snow will gradually wind down Friday night as the upper low moves east of the state and the heavier precip rates end. This means a transition back towards rain with temperatures in the mid to upper 30s. There will be no real cold air advection behind this low. Generally warmer temperatures and cloudy conditions will follow Saturday into Monday. Temperatures will be in the 30s at night and in the upper 40s to near 50F during the day...which will melt the snow. There is another shortwave that will cross the area but timing is very uncertain with solutions ranging from Saturday night to Monday. The one certainty is that this system will be rain. && .AVIATION /16Z TUESDAY THROUGH SATURDAY/... NEAR TERM: Msly MVFR clgs and vsbys with intermittent sn and rn shwrs tdy and msly sn shwrs tngt can be xpctd across Nrn TAF sites with brief IFR clgs/vsbys possible with heavier sn shwrs. Otherwise low VFR clgs for Downeast sites, with brief MVFR clgs possible attms. SHORT TERM: MVFR cigs with tempo IFR conditions in snow showers will prevail Wednesday morning. Conditions will lift to VFR in the afternoon and persist until Thursday night when the trend will be towards IFR cigs for all sites...and LIFR/VLIFR vis in snow north of a line from GNR to HUL. This will continue all of Friday and into Friday night. LLWS is possible. Conditions will improve Saturday to a prevailing condition of MVFR cigs. && .MARINE... NEAR TERM: Will cont the SCA ovr our outer MZs tdy and tngt msly due to winds, but also marginal wv hts with cont`d llvl cold advcn NW winds. Primary wv pds will be msly in the 5 to 6 sec range, typical of short fetch off-shore wind directions. Kept close to WW3 wv guidance for fcst wv hts for this ptn of the fcst. SHORT TERM: SCA conditions may still exist early Wednesday morning, but winds and seas will quickly diminish during the morning. The next big event will be the potential for the season`s second gale event beginning Thursday night and going into Friday night. SCA conditions will follow the gale and last into Saturday evening. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...Small Craft Advisory until 4 AM EDT Wednesday for ANZ050-051. && $$ Near Term...VJN/MCB Short Term...MCW Long Term...MCW Aviation...VJN/MCW Marine...VJN/MCW
Area Forecast Discussion...UPDATED
National Weather Service Norman OK
1033 AM CDT Tue Oct 25 2016 .UPDATE... Removed morning fog mention in parts of southern and southeastern Oklahoma where the fog has dissipated. Increased cloud cover today. Delayed rain chances tonight a few hours. && .DISCUSSION... Mostly cloudy, warm, and humid conditions will continue for the rest of today. High level cloud cover will continue to overspread Oklahoma and north Texas today, however no rain is expected during the daylight hours as the mid levels of the atmosphere remain dry. The air should remain capped. Forecast highs in the upper 70s to lower 80s appear to be on track. Latest models, particularly the HRRR, keep depicting showers and storms moving into northern Oklahoma from Kansas after 9 pm this evening at the earliest, and probably not until after midnight tonight. Thus, delayed the rain chances tonight. A few strong to perhaps severe storms are possible in far northern Oklahoma late tonight where MUCAPE is forecast to be 800-1400 J/kg and 0-6 km shear will be near 25 kt. Marginal hail up to quarter size and marginal wind gusts up to 60 mph could occur. Not confident that severe storms will occur. The greater storm chances and coverage are expected to stay north of the Oklahoma Kansas state line. Products will be updated shortly. MBS && .PREV DISCUSSION... /issued 630 AM CDT Tue Oct 25 2016/ AVIATION... High clouds will increase this morning from west to east. Meanwhile, some fog and low clouds have recently formed across southeast Oklahoma. Low clouds with MVFR ceilings may develop for a few hours in and around OKC/OUN and perhaps LAW but confidence is not high. Later this evening and overnight, widely scattered showers and storms will be possible mainly across north central Oklahoma after 8z. MVFR conditions are possible with thunderstorms. PREV DISCUSSION... /issued 320 AM CDT Tue Oct 25 2016/ DISCUSSION... High clouds will continue to increase today ahead of a fast moving shortwave trough. Being late October this should have some impact on insolation this afternoon. RAP and NAM soundings indicate the best opportunity for afternoon storms will be across southwest Oklahoma and western north Texas. Even this area will likely remain capped. This evening and overnight, showers and a few thunderstorms may develop, especially across north central Oklahoma. Will keep high chance POPs for this area. An associated front will enter northwest Oklahoma around sunrise Wednesday, while a few elevated showers move across north central and central Oklahoma. By mid to late afternoon, the frontal boundary will become nearly stationary north and west of Interstate 44. Capping will be an issue again, but an isolated storm or two may form ahead of front during peak heating (central and south central OK). After Wednesday, a mid and upper ridge centered over northern Mexico will build east into Texas and the Southern Plains. This will bring yet another period of dry weather with well above average temperatures. A weak front should push into far northern Oklahoma Saturday afternoon, but areas ahead of the front will warm into at least the mid and upper 80s. Near record high temperature are expected at least Friday and Saturday. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 78 62 81 57 / 0 30 30 10 Hobart OK 79 63 83 55 / 0 10 10 0 Wichita Falls TX 80 63 84 58 / 0 10 10 0 Gage OK 80 58 83 48 / 0 20 0 0 Ponca City OK 80 63 80 52 / 0 50 30 0 Durant OK 80 60 82 61 / 0 10 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ 17/23
...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight) Issued at 319 AM CDT Tue Oct 25 2016 A lead upper level trough ahead of a nearly stationary longer wave length upper trough off the western coast of the US will lift northeast across the plains Tonight. A lee surface low across western KS will deepen through the day and move northeast into south central NE by 00Z WED. A surface cold front will move from eastern CO, eastward across west central KS through the afternoon hours and into the western counties of the CWA by 02Z WED. Point forecast soundings from the 00Z NAM and WRF models show an EML at around 735MB overspreading the warm sector during the afternoon hours and through the evening hours as well. There may be enough ascent ahead of the weak upper trough and lift along the surface front for scattered thunderstorms to develop southwest along the surface front from southern NE across the central counties of the CWA after 3Z. The only model that shows deep moist convection developing after 00Z is the 00Z GFS model. The WRF solutions keep the CAP strong enough that only isolated storms develop after 9Z along the surface front along and southeast of the KS turnpike. The most favorable environment for strong to severe thunderstorms would be during the late afternoon and early evening hours where MLCAPES will increase to 1500-2000 J/KG with 0-6KM shear increasing to 25 to 30 KTS. However the cap may prevent storms from developing along the front. If surface based storms manage to break the cap, they may become severe with the potential for large hail and damaging wind gusts across north central KS. If the NAM, WRF and RAP solutions end up verifying then thunderstorms may not develop until near midnight across the eastern and southern half of the CWA. The MUCAPE will decrease to 1000-1500 J/KG but the 0-6KM shear will increase slightly to 30 to 40 KTS. Thus a strong or severe thunderstorms will still be possible. If deep moist convection does not develop until around 6Z the primary hazard with any strong to severe storm would be large hail, since the boundary layer may decouple enough to prevent severe wind gusts. Rainfall will depend on thunderstorm coverage and intensity. If storms develop along the front around 6z and last through the early morning hours, then some locations across east central KS may pick up a quarter to a half inch of rainfall. Highs this afternoon will reach the mid to upper 70s this afternoon as WAA at 850mb increases 850mb temperatures between 14 and 18 degree C. The boundary layer should mix to around 850mb and any stratus this morning should mix out during the late morning and early afternoon hours. South winds will increase to 15 to 25 MPH with higher gusts from the late morning hours through the afternoon and into the evening hours. .LONG TERM...(Wednesday through Monday) Issued at 319 AM CDT Tue Oct 25 2016 The mid range and extended forecast will be dominated by an upper ridge over the southern US resulting in mainly zonal flow over the region. A series of dry cold fronts will cause up and down temperatures. The first front passes through the area Friday night, therefore Friday appears to be the warmest day. High temperatures are forecasted to reach around 80, but only cool into the low to mid 70s over the weekend. Another front approaches the area on Monday so highs slightly increase only to drop into the 60s by Tuesday. A deepening trough over the western US will allow more shortwaves to track over the central plains, which will bring chances for showers and storms through mid week. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 637 AM CDT Tue Oct 25 2016 VFR conditions are expected throughout the TAF period. Southerly winds will increase near midday with sustained 10-15 knots and gusts 20-25 knots. With a strong pressure gradient in place, the current expectation is for winds to continue gusting into the overnight hours. Introduce VCTS for MHK at 05Z and the Topeka terminals at 07Z. Future outlooks may need to introduce a TEMPO group for TSRA, especially at the Topeka terminals. However, confidence is too low at this point. Any remaining shower/storm activity will shift southeast of the terminals near the end of the period. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Gargan LONG TERM...Sanders AVIATION...Baerg
Area Forecast Discussion
National Weather Service Hastings NE
312 PM CDT Tue Oct 25 2016 ...Warmer or Much Warmer Than Normal Temps Cont for the Next Week with Most Locations Remaining Bone Dry... .SHORT TERM...(This evening through Wednesday) Issued at 312 PM CDT Tue Oct 25 2016 Aloft: A ridge was over the Plains with a weak shortwave trof moving thru it. WV imagery showed this trof from WY-CO-NM. This trof will move thru tonight. The ridge will retrograde to the Rockies in its wake tomorrow with NW flow over the Plains. Surface: Cyclogenesis was underway. Low pres will emerge into Neb this eve and will cross SE Neb tonight on its way into IA. A warm front will E/SE from this low but there will be no real cool front. Just a trailing trof/dryline near Hwy 283 at 19Z. This trof will cross the fcst area tonight. Weak high pres will temporarily nose into the region tomorrow. Another very warm day was in progress with breezy SE winds gusting up to 25 kts at times over the SE 1/2 of the fcst area. The fog that develop W of Hwy 183 lifted into a stubborn bank of stratus that has been slow to erode. This has kept temps cooler with MCK at 55F and LXN at 60 at 19Z. Until Sunset: P-M/cloudy. Probably dry. As mentioned in the 1259 pm version of this product...an EML/cap has advected over the region. Temps will peak 75-84F over much of the fcst area with dwpts 55-61F. With very steep (8C/km) mid-lvl lapse rates above this...MLCAPE should maximize as high as 1500 J/kg. However... forcing associated with the trof is weak. Mesoanalysis shows CINH less than -100 J/kg ...and we are approaching peak heating. We might see an isolated shwr/tstm E of hwy 281...but don`t bet on it. The cap will probably prevent/delay convective initiation long enough for the sfc convergence/trof to be E and S of the fcst area. Anything that develops will probably be after sunset and will be over Ern Neb and/or Ern/Cntrl KS. That is exactly what the HRRR and HRRRX are showing. W of Hwy 281 over Neb there`s zero chance of rain. Low temps tonight still way above normal (15-20F). Wed: Back to very nice wx with high temps still 10F above normal. NW winds will be a little brisk thru early afternoon (12-16 mph). .LONG TERM...(Wednesday night through Tuesday) Issued at 312 PM CDT Tue Oct 25 2016 Aloft: A ridge will dominate over the Cntrl USA which means above to much above normal warmth will cont. A shortwave trof will move in off the Pac and thru the ridge Fri night into Sat. Another weaker trof is slated to move thru Mon. Surface: A cool front will make its way thru the Wrn USA the next few days. Low pres will form and move E thru the Nrn Plains Fri- Sat. The cool front will move thru Fri night into Sat morning. High pres will briefly nose in Sat-Sun with the next low forming and cool frontal passage occurring Mon. There is no end in sight to the anomalous warmth. Thu-Fri and Mon are looking incredibly warm (at least 20F and close to 25F Fri). Raised temps above fcst initialization Fri in coord with neighboring offices. Mon we are probably not warm enough yet but there`s time. No high-impact/hazardous wx is currently foreseen...but fire wx could be a concern if winds can coincide with low RH. No obvious threat are seen yet. There is no potential for even minor rainfall. This will go down as one of the driest Oct`s on record at GRI (and likely many other locations). && .AVIATION...(For the 18Z KGRI/KEAR TAFS through 18Z Wednesday) Issued at 1258 PM CDT Tue Oct 25 2016 Significant Wx: WSHFT to W 23Z-02Z but with light wind speeds. This Afternoon: VFR with increasing clouds. SCT CU will form around 4K ft and lift to 5K ft. Then patchy multi-layered clouds will increase at or above 10K ft. SE winds 10-15 kts with gusts to near 20 kts initially will diminish. Expect WSHFT to W at EAR around 23Z. There could be an isolated shwr or tstm DSNT NE or E of both terminals. Confidence: High Tonight: VFR decreasing clouds from W-E. Lgt mainly W winds will become NW after 06Z. Confidence: High Wed thru 18Z: VFR. Just a couple shreds of cirrostratus possible around 25K ft. NW winds increase 12-15 kts. Could see a few gusts to 20 kts after 14Z. Confidence: High && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ SHORT TERM...Kelley LONG TERM...Kelley AVIATION...Kelley
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
450 PM EDT Tue Oct 25 2016 .SHORT TERM...(This evening through Wednesday night) Issued at 450 PM EDT TUE OCT 25 2016 20z sfc analysis shows high pressure moving through the Ohio Valley. This is providing mostly clear skies, aside from some high clouds drifting through from the northwest. The cool high to the north and good sunshine yielded temps ranging from the lower 70s south to low 60s north this afternoon. Dewpoints, meanwhile, were able to mix down into the low to mid 30s most places, but many spots did see some 20s. The winds were generally light and variable this afternoon. The models are in good agreement aloft through the short term portion of the forecast as they all bring a developing trough into the Great Lakes by Wednesday evening. This will be accompanied by a batch of energy passing through the Ohio valley into Thursday morning. The GFS is slight stronger with this feature than the ECMWF and Canadian, but actual differences are relatively small. Accordingly, a general model blend was preferred with a lean toward the HRRR and NAM12 and significant consideration given to the dry air aloft (and co-op MOS) that has been resulting in a larger than forecast diurnal range of late for the area. Sensible weather will feature another cool and mostly clear night with light to calm winds. This will set the stage for chilly low temperatures and likely areas of frost in the deeper valleys. Patchy dense fog will again be found near the rivers late, as well, helping keep those spots from seeing much in the way of frost. The frost is anticipated to be a bit more widespread than last night so have issued a frost advisory for our eastern 2/3rds where radiational cooling will be maximized. More sunshine and winds switching to the southwest will mean a warm day Wednesday with low to mid 70s anticipated for highs. Attention will then turn to the, unfortunately drying, cold front inbound for Wednesday night into Thursday morning. Despite the withering of the model QPF with this, there will be enough elevated instability and dynamics aloft to yield a stray thunderstorm or two for mainly northwest parts of the area overnight into Thursday morning. Have included this in the grids and HWO. Again started with the CONSShort/ShortBlend for the bulk of the grids with adjustments to the temps tonight and to a lesser extent on Wednesday night revolving around terrain differences, as well as knocking dewpoints down in the afternoon Wednesday. As for PoPs - did bring them up into the slight chance range Wednesday night - a bit higher than consensus MOS guidance - as the front starts to press into the area. .LONG TERM...(Thursday through Tuesday) Issued at 355 PM EDT TUE OCT 25 2016 An upper level trough axis will be swinging through the Great Lakes at the start of the period, as a surface low tracks across the Ohio Valley. An associated cold frontal boundary will move through the area Thursday afternoon, bringing scattered showers and a slight chance of thunder. The remainder of the extended period will likely remain mild and dry with high pressure parked over the southeastern CONUS. High pressure will build into the region by Friday morning, allowing for valley temps to drop off into the upper 30s/low 40s. However, a quick return of warm air will take place Friday as the upper ridge builds into the southeastern US. With the return flow in place, temperatures should rebound into the upper 60s and lower 70s Friday afternoon. Well-above normal temperatures are anticipated on Saturday with most locations reaching the upper 70s, possibly eeking out 80 degrees in spots. If we hit 80 degrees here at the Jackson Weather Office, we will tie for the most 80 degree days in October on record. As high pressure gradually shifts towards the Atlantic Ocean Sunday through Tuesday, conditions will be dry as high temperatures reach the mid and upper 70s each day with lows in the upper 40s/low 50s. Tuesday may be another day that afternoon highs reach 80 degrees. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 210 PM EDT TUE OCT 25 2016 Mainly VFR conditions and light winds will be seen through Wednesday morning. Some patchy dense valley fog is expected early this morning along the rivers, but should not impact the TAF sites. However, as was the case this morning - some of the helicopter pads - especially the one near Manchester could get caught up in the dense fog for a time late tonight into dawn Wednesday. && .JKL WATCHES/WARNINGS/ADVISORIES... Frost Advisory from 1 AM to 10 AM EDT Wednesday for KYZ052-060- 069-080-085>088-104-106>120. && $$ SHORT TERM...GREIF LONG TERM...JVM AVIATION...GREIF
Area Forecast Discussion
National Weather Service Lubbock TX
330 PM CDT TUE OCT 25 2016 .SHORT TERM... High clouds thinning now just to the east of a weak upper impulse edging into the high plains. A small cumulus field in eastern New Mexico has responded to the surface warming in that area, and has some potential for brief thunder development close to our southwest corner late this afternoon. Otherwise we are not seeing response across the border into our Texas counties. An earlier HRRR run was one of few solutions briefly convecting in this area, but has been vacant of thunder development in recent hours. The surface based convectively available energy is significant today, while a small area of inhibition still was needing removal. Owing to the delayed surface warming, and lack of solution support, this forecast will remain void of thunder mention for this evening and overnight. Clearing skies will follow overnight, while a surface trough with mild south to southwesterly flow will dominate. Late in the night, the trough will edge south-southeast with low level flow gradually veering and drying. A weak cool front will cross our northwest corner just before sunrise with additional drying and slight cooling. This front will bisect the area northeast to southwest by mid morning Wednesday with surface flow turning north to northeast and perhaps even a few breezier gusts close to 20 mph that might briefly feel like a real cold front. Minimal thunder chances along this front in our southeast Wednesday, will leave out for this forecast with very little solution support. Stout upper level ridging will build in from the west and clear skies will lead to yet another above normal temperature day by afternoon. RMcQueen .LONG TERM... Fairly benign weather is expected through the extended forecast with temperatures residing well to the warm side of average. This will occur as an upper level ridge builds in from the southwest late week. The ridge will gradually deamplify and shift to the Deep South next week leaving behind southwesterly flow aloft for West Texas. Dry conditions will prevail as any embedded disturbances will be directed up and around the high/region. One shortwave trough traversing the Midwest Saturday may push a weak cold front toward or briefly into the CWA late Saturday, but it will quickly retreat back northward with minimal impacts locally. A similar scenario may unfold Monday night or Tuesday. Altogether, the extended forecast is dry and continues to favor the warm side of guidance, as has generally verified the best as of late. && .LUB Watches/Warnings/Advisories... None. && $$ 05/23
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
308 PM CDT Tue Oct 25 2016 .SHORT TERM...(This evening through Wednesday) Issued at 307 PM CDT Tue Oct 25 2016 Weak surface cyclogenesis taking place in north central Kansas ahead of a modest wave in the zonal flow aloft. Cirrus has been persistent but not terribly thick ahead of this wave, and in concert with gusty south winds, highs have pushed into the mid 80s in some locations. Despite dewpoints reaching into the lower 60s, an elevated mixed layer has kept convective inhibition well over 100 J/kg per RAP analysis. Concern for convection in/near peak heating continues to wane with an overall slower trend to the wave and the cap in place. The wave is still expected to deepen as it passes through Central Plains tonight into early Wednesday, and with well above normal moisture in place, should see at least scattered convection develop, with coverage likely increasing as both moisture and low level jet ramp up. Lapse rates aloft should be steep enough for around 1000 J/kg of elevated CAPE along with some shear for minor potential for some large hail with a few storms. Precip will likely linger in east central Kansas after sunrise Wednesday, but subsidence behind the trough quickly builds in by late morning. The modified continental airmass moving in should only drop highs back into the low to mid 70s. .LONG TERM...(Wednesday night through Tuesday) Issued at 307 PM CDT Tue Oct 25 2016 High pressure gradually drifting eastward from the CWA on Thursday will allow for one final mild afternoon with highs in the lower to middle 70s. As the upper ridge amplifies over the central plains by Friday, the sfc pressure gradient increases southerly winds at 10 to 20 mph sustained throughout the afternoon. In addition, 925 mb temps are near or above 20 C from all guidance, suggesting lows Friday morning in the upper 50s with highs in the lower and middle 80s to be common. Saturday morning lows may also remain pretty mild around 60 degrees, before some high clouds increase and a weak cold front passes through dry. Areas along and south of I 70 may once again reach the upper 70s Saturday before the cooler airmass drops highs back into the lower 70s on Sunday. Extended guidance remains pretty consistent for Halloween as broad troughing over the northern plains pushes another cold front through aft 00Z. The cold air lags somewhat behind the boundary with readings in the upper 70s for highs Monday and overnight lows into the lower 50s. Shortly thereafter on Tuesday, GFS becomes the more progressive solution with a shortwave trough lifting from the southwest Tuesday and Wednesday. Low end chances for thunderstorms were mentioned since the ECMWF advertises a dry forecast with the slower progression of the wave progged to arrive later in the week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1246 PM CDT Tue Oct 25 2016 Only minor changes to the forecast. Uncertainty on timing of precipitation remains somewhat high however with a wide range of possibilities from guidance. Visibilities could reach IFR in the stronger storms however. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...65 LONG TERM...Prieto AVIATION...65