Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/23/18

Area Forecast Discussion
National Weather Service Binghamton NY
1033 PM EDT Wed Aug 22 2018 .SYNOPSIS... High pressure will move into the region tomorrow and bring dry weather and plenty of sunshine through the end of the week. As the high moves east of the area, southerly winds will bring humidity and a chance for showers back to the region. && .NEAR TERM /THROUGH THURSDAY/... With the late evening update, rain chances were updated based on radar trends and that the HRRR and RAP both linger some pesky showers into the overnight. Cloud cover also looks to be persistent into the overnight. However, high pressure will begin to build in allowing for generally clearing skies. Left out mention of fog overnight as the transition to high pressure will keep winds up enough to help mixing. Although a few deep valleys may see fog for a slight time before sunrise. Low temperatures should be in the 50`s. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/... A quiet weather pattern is in store for the region as ridging both surface and aloft will build over CNY/NEPA This will bring generally clear to partly cloudy skies. Humidity levels also look comfortably low, given the Canadian origin (which was previously Alaskan...and then previously Siberian) of the incoming air mass. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Warm front will approach later in the day on Saturday, moving through Saturday night, bringing a chance of showers and slight chance t`storms. Most of the day Saturday is looking dry at this time, with highs in the upper 70s to lower 80s. With the weak upper trough moving through on Sunday, and much higher level of instability, could see some scattered late day t`storms around. Otherwise, it`ll be partly sunny and warmer with highs in the lower to mid-80s. Lows in the upper 50s to mid-60s over the weekend. The forecast area remains on the northern periphery of a strong upper level ridge Monday through Wednesday. Weak shortwaves and MCS type convection will likely ripple through the westerly flow pattern impacting our forecast area at times...especially our NY zones. The source region of moisture looks to be more from the central Plains region this time around. Therefore, heavy, torrential, tropical-like downpours are looking less likely during this time period. Gusty t`storm winds may be more of an issue. These details will of course be worked out as we move forward in time. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... Mainly SHRA affecting the area with only a few lightning strikes reported. Pockets of +SHRA are moving through and will continue to do so through the evening. Conditions forecast to go VFR in all locations later this evening as high pressure builds into the region. Northwest flow will keep widespread fog limited overnight. Good VFR will be the story on Thursday as high pressure continues to move over the region. Winds will gust to 25 kts at times as the atmosphere becomes mixed by afternoon. Outlook... Friday through Sunday...Mainly VFR. Early morning fog possible, especially KELM. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS... WFO CTP/ MWG NEAR TERM... WFO CTP/MWG SHORT TERM... WFO CTP LONG TERM... WFO CTP AVIATION... WFO CTP
Area Forecast Discussion
National Weather Service Denver/Boulder CO
843 PM MDT Wed Aug 22 2018 .UPDATE... Issued at 843 PM MDT Wed Aug 22 2018 Forecast is largely on track with isolated thunderstorms over the Palmer Divide and a few more in the mountains. Satellite imagery shows large scale lift and considerable convection occurring along the approaching trough from the west, and with the right entrance region of a 75 knot jet max, we expect those showers and storms to continue and spread east across the mountains overnight. Can`t rule out redevelopment of a few more storms across the plains as well later tonight into early Thursday morning with this weather disturbance. Otherwise, main change was to add areas of smoke to the forecast tomorrow. Flow behind this trough goes west/northwest, which will bring in a large plume of smoke evident on visible satellite imagery earlier today across northern California, northern Nevada, southern Oregon, and southern Idaho. HRRR Smoke model also shows this same evolution so very hazy/smoky skies expected again on Thursday. Airmass will dry considerably with the developing westerly downslope breezes. Gusty winds expected across the mountains by morning, and spreading east across the plains through the day. && .SHORT TERM...(This evening through Thursday) Issued at 336 PM MDT Wed Aug 22 2018 The current low center is seen on GOES-16 satellite over Idaho. This is projected to stay to the North of the state and just brush the northern Colorado border. With the moisture levels higher today and PW values over an inch, convection is expected over the higher terrain of the mountains and Palmer Divide this afternoon and into the early evening hours. The storms will be isolated to scattered with the main impacts being moderate to heavy rain, lightning, gusty winds and possibly some small hail. Some storms could move off the higher terrain onto the adjacent plains, but will not hold together for too long given more stable conditions to the east. However, if storms are able to hold together they could drop periods of moderate to heavy rain. Clouds will scatter out overnight leaving a chance of patchy fog development over the far eastern plains. Lows are expected to be slightly warmer than days past with temperatures in the upper 50s over the plains and 40s in the mountains. For Thursday, the upper low and trailing trough will push eastward leaving the state in predominantly westerly flow. Increased winds at the base of the trough and being on the more stable side of the jet will allow for downsloping Thursday. Moisture is expected to drop slightly as the ridge flattens out, but should still be high enough for isolated storms over the mountains. With the influence of the downsloping and deepening lee side low conditions should stay too stable on the plains to support convection Thursday afternoon. Winds will increase across the northern mountains and foothills with some gusting to 40 mph by the afternoon. Temperatures will rebound quickly back into the upper 80s on the plains and 70s in the mountains. .LONG TERM...(Thursday night through Wednesday) Issued at 336 PM MDT Wed Aug 22 2018 Initially, a weak upper ridge is forecast to pass over the state Friday and Saturday bringing warmer temperatures and a continuation of dry conditions on the plains. Temperatures on the plains will make it back into the lower 90s. Moisture from Arizona and Utah will move into the mountains producing scattered afternoon shower activity. After Saturday, an upper trough developing over the Pacific Northwest will turn the flow over Colorado to southwesterly. Moist southwesterly flow aloft will continue into next week. Mountain areas will continue to be the main recipients of afternoon shower activity. Next Tuesday night or Wednesday, models are showing a deeper trough moving into the northern Rockies which will move across Colorado. An increase in showers should be seen along with some cooler temperatures in the mountains and onto the plains on Wednesday. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 843 PM MDT Wed Aug 22 2018 Isolated storm threat this evening is over, with only a 10% chance or so that a storm redevelops in the Denver area TAF sites overnight due to upper level weather disturbance. VFR conditions will prevail. South/southwest winds around 10 knots tonight will turn more westerly Thursday morning and increase to around 15G22kts for most of Thursday afternoon during peak heating and mixing. We`ll see some smoke/haze come in by 15Z with limited slant range visibility likely and possible ILS approaches. At this time, surface visibility is expected to stay greater than 6SM. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Barjenbruch SHORT TERM...Bowen LONG TERM...Dankers AVIATION...Barjenbruch
Area Forecast Discussion...Updated
National Weather Service Billings MT
833 PM MDT Wed Aug 22 2018 .UPDATE... Convection in the west so far this evening has been less than expected. Although the strongest upward forcing is aimed right at our BEartooth/Absaroka mountains, the lack of moisture available is limiting coverage and strength of convection. The area where moisture is better per precip water values (Powder River and Southern Rosebud) is actually getting a bit more robust showers and lightning. While isolated to scattered showers will probably continue overnight in our west due to the proximity of the upper low, we may eventual see an increasing coverage and strength of convection in our east late tonight as upper low and forcing track that way. That said, we still dont expect to see any real strong or severe storms, mainly garden variety. The latest HRRR cycles support this thinking. Thus, we have adjusted PoP`s accordingly. Rest of forecast looks fine. BT && .SHORT TERM...valid for Thu and Fri... An upper low centered over Idaho is spreading clouds northeastward into southern Montana and northern Wyoming this afternoon. Showers and thunderstorms are occurring over Idaho, far southwest Montana, and central and southern Wyoming. The upper low should move eastward tonight, and as it does, it should bring better dynamics over the area and help to generate showers and thunderstorms over our area. Shower and storm activity should be isolated initially and then increase to scattered by late this evening. Any thunderstorms that develop late this afternoon and early this evening would have enough instability available to produce some gusty winds and small hail, but we are not expecting severe weather at this time. Scattered showers and general thunderstorms are possible overnight and then should end from west to east during the day on Thursday as the upper low continues to move eastward. Shortwave ridging should build in late Thursday into Friday, bringing a period of dry and warm weather. An upper-level shortwave trough and associated surface cold front should then cross the region from west to east Friday afternoon into the evening. The upper trough and surface front should help to generate scattered showers and thunderstorms across the region late Friday afternoon and evening, with the greatest chance north of Billings. High temperatures should generally be in the 80s Thursday and Friday, with Friday being a few degrees warmer than Thursday. RMS .LONG TERM...valid for Sat...Sun...Mon...Tue...Wed... Quasi-zonal flow over the region on Saturday will bring mainly dry conditions. A digging upper trough over the Pac NW and associated low then look to eject multiple waves of energy over the area increasing shower and thunderstorm chances Sunday through at least Tuesday as the trough and low gradually move towards the Northern Rockies. Drier conditions look to return for Wednesday as shortwave ridging builds over the region. While there remains model uncertainty in the timing and placement of the aforementioned waves and precipitation, an unsettled weather pattern looks to dominate the long term. High temperatures look to range from the 70s to 80s most days, with the coolest day being Tuesday, with highs in the upper 60s to lower 70s. Low temperatures look to range from the upper 40s to 50s most nights/mornings. STP && .AVIATION... Isolated to scattered thunderstorms are moving off the mountains and foothills, affecting KLVM VC at this time, but expected to spread to KBIL and KSHR. Additional ISOLD showers/thunder have developed near K4BQ and will move toward KMLS VC if persist. MVFR conditions are possible in the thunderstorms along with gusty winds. Scattered showers and a few thunderstorms will move through the entire area overnight with MVFR conditions possible. Expect areas of mountain obscuration through tonight. AAG/STP && .PRELIMINARY POINT TEMP/POPS... Thu Fri Sat Sun Mon Tue Wed ----------------------------------------------------------- BIL 057/083 056/087 053/080 055/084 054/075 050/071 051/079 33/T 01/U 31/U 11/U 12/T 32/T 20/U LVM 049/081 048/083 044/081 048/080 047/072 045/070 044/076 52/T 02/T 31/U 11/U 24/T 43/T 20/U HDN 055/084 054/089 051/081 054/087 053/078 050/071 049/081 33/T 00/U 31/U 11/U 23/T 32/T 20/U MLS 059/081 055/087 054/080 056/086 056/079 052/071 050/080 36/T 00/U 51/U 11/U 22/T 42/T 21/U 4BQ 059/081 055/089 054/082 054/089 055/083 052/074 050/081 35/T 10/U 31/U 11/U 11/U 43/T 31/U BHK 057/080 054/089 053/080 054/086 054/080 050/073 049/079 36/T 20/U 51/U 21/U 21/U 43/T 31/U SHR 052/081 051/089 049/083 052/088 052/082 049/074 048/081 22/T 10/U 21/U 01/U 11/U 22/T 21/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$
Area Forecast Discussion
National Weather Service Flagstaff AZ
852 PM MST Wed Aug 22 2018 .SYNOPSIS...Deep monsoon moisture will remain over northern Arizona through Friday. This will result in good chances for afternoon and evening thunderstorms each day. A downturn in shower and thunderstorm activity is possible over the weekend and especially early next week. && .UPDATE...Rain and thunderstorm activity continues along and south of I-40 this evening. The heaviest precipitation remains over southern Yavapai and northern Gila counties where Flash Flood Warnings remain in effect for a few areas. The Flash Flood Watch was cancelled for northern portions of Coconino County as the heaviest rain fell mostly in Yavapai County through the afternoon. For the overnight hours, expect to see shower and thunderstorm activity gradually weaken and end into the early morning hours across areas south of I-40. A few additional areas could see heavy rainfall over the next couple of hours as a few stronger cells remain across northern Gila County moving slowly to the northeast. && .PREV DISCUSSION /238 PM MST/...Ample monsoon moisture remains in place across northern Arizona today. A trough is moving through the Great Basin to our north and providing a focus for more organized thunderstorm activity across northwestern Arizona, where a Flash Flood Watch remains in effect through this evening. This area has seen 1-2" of rain in the last 24 hrs and the ground is already saturated. Any additional heavy rainfall could cause flooding. Other storms producing very heavy rain this afternoon along the I-40 corridor including the Ash Fork area. Latest HRRR suggests storms in this area could continue for several more hours. Elsewhere, scattered to numerous showers and storms will persist through the evening hours. Some of the high-resolution model guidance suggests activity persisting into central Arizona overnight and we have kept scattered activity in the forecast for areas generally from Flagstaff southward overnight. The steering flow shifts to west to east on Thursday as the high pressure ridge flattens in response to the passing trough. Similar atmospheric moisture and instability profiles are anticipated, would should again lead to scattered/numerous thunderstorms. Some of this hinges on what happens overnight tonight and perhaps lingers into the morning hours. An active monsoon thunderstorm pattern will continue through the week. Forecast trends point toward decreasing coverage of storms over the weekend as moisture thins out. This downward trend could last into next week. && .AVIATION...For the 06z package...Scattered showers and thunderstorms will continue south of a line from KFLG to KSJN through the early morning hours. Local IFR/MVRF conditions are possible near heavier showers. Showers and thunderstorms will develop again tomorrow after 18Z across northern Arizona. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Thunderstorms remain throughout northern Arizona Wednesday evening and through midnight. Ample monsoon moisture will remain Thursday with a good chance of showers and thunderstorms. Overnight activity is possible. Friday will see scattered showers throughout northern Arizona. Saturday through Monday...A drier air mass will slowly filter southward from the UT/AZ border starting Saturday. The drier air will lead to a downturn, but not dissipation, in shower and thunderstorm activity for areas north and east of the Mogollon Rim by Monday. The White Mountains region can still expect high chances for showers and storms. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...ET/MCT AVIATION...ET FIRE WEATHER...NL/JJ For Northern Arizona weather information visit
Area Forecast Discussion
National Weather Service Wilmington NC
905 PM EDT Wed Aug 22 2018 .SYNOPSIS... A few showers and thunderstorms may precede an approaching cold front through tonight. The front will clear the coast early Thursday morning and bring cooler and drier conditions to the area through Friday. A warming trend is expected over the weekend, with seasonable warmth and humidity Sunday through early next week. Above normal temperatures are possible Tuesday and Wednesday. && .NEAR TERM /THROUGH THURSDAY/... As of 8 PM Wednesday...While the HRRR has been emphatic about scattered convective development for multiple runs storms thus far have been inhibited by mid/upper dry air. The dry air has limited areal extent in addition to vertical growth. At any rate there will be a chance of showers/thunderstorms until the front passes through overnight. The front is currently located just NW of GSB-SOP line and is pushing quickly toward the southeast. Thus with FROPA, less humid conditions with cooler temperatures expected to spread in during the early morning hours. Previous discussion...A few very light and isolated showers have developed well inland ahead of the surface front. Surface analysis and satellite imagery indicate the front is close to a line from Raleigh to Rockingham to Lancaster at 18Z. Surface- based instability remains marginal west of I-95, so would be surprised to see anything more than weak shower development there over the next few hours. The potential for scattered showers and a few storms will continue along and ahead of the front, which should push off the coast by 06Z if not a little earlier. The airmass does become more unstable east of I-95, so activity could become a little more vigorous late this afternoon and early evening. A small portion of the Cape Fear region east of an Elizabethtown to Whiteville to Shallotte line remains in an area outlined by SPC for a marginal risk of damaging wind gusts, if any storms do manage to get going. High pressure will build in behind the front, with a wind shift overnight followed by clearing skies Thursday. Highs on Thursday are expected to top out in the mid 80s as dewpoints fall into a 60-65 degree range. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/... As of 230 PM Wednesday...High pressure centered across the Mid- Atlantic states will bring relatively cool & dry air southward across the Carolinas. Precipitable water values Thursday night should fall to around an inch on the coast and 0.75" inland, while 850 mb temps slip to around +14C. Mainly clear skies and the best radiational cooling we`ve seen in over a month should allow lows to fall deep into the 60s inland, certainly the coolest we`ve seen since July 10th, and June 5th-6th prior to that. The high will move off the Mid-Atlantic coast during the day Friday, but will maintain a NE-SW orientation as a weak inverted trough develops over the Gulf Stream off the Georgia and South Carolina coast. This should maintain low-level winds from the northeast, with dry air draining southwestward into our area. Dewpoints away from the coast should mix down into the upper 50s Friday. Even with plenty of sunshine highs should only reach the mid 80s, with east- facing beaches potentially only approaching 80 with a healthy onshore wind all day. The inverted trough will try to shift a little closer to the coast Friday night, but I`m hopeful showers will remain off the coast until midnight. I`ve painted in some slight chance PoPs for showers (no thunder due to the subsidence inversion aloft) along the beaches south of Cape Fear late Friday night. Lows shouldn`t be quite as cool, with mid 60s expected inland and upper 60s to around 70 near the coast. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... As of 230 PM Wednesday...H5 weakness will prevail across the Carolinas between the subtropical ridge over TX-AL and other ridge off the coast Sat and Sun. The subtropical ridge will build ENE to over TN during Mon and TN/NC during Tue-Wed. In the meantime, a weak area of shear aloft along with a coastal trough (the old front) drifting back onshore during Saturday may be enough to spark widely scattered showers and tstms. Otherwise, a more typical summertime pattern will develop the first part of next week with mainly widely scattered diurnally driven convection each afternoon and evening. The aforementioned ridge could suppress convection some Tue-Wed time frame. Temperatures will gradually warm around normal Sat-Sun, then above normal Mon-Wed. MEX highs may be a touch too cool Tue-Wed. Otherwise, no significant impacts are expected at this time. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... As of 00Z...Cold front very evident on radar moving through Raleigh. Interestingly, most of the convection seems to be post frontal. The NAM increases the convection through the overnight hours. Look for the front to move through LBT around 05Z, reaching the coast around 08Z. Did add some thunder, however confidence only moderate. Winds will shift decisively to the north, post frontal. Thursday, a beautiful day with unseasonably cooler and drier conditions with a continued northerly wind. Extended Outlook...Generally VFR conditions as a surface ridge of high pressure extends across the interior Carolinas. Periods of MVFR ceilings possible Friday and Saturday as a weak coastal trough develops and moves inland. Showers may accompany this feature. && .MARINE... NEAR TERM /THROUGH THURSDAY/... As of 8 PM Wednesday...The current forecast is on track and only minor changes made with the latest update. Area marine observations indicate southwest flow prevailing ahead of a front slated to move across the waters early Thursday morning. The flow is projected to veer from the southwest to the west, and eventually northwest as the boundary shifts through. Choppy seas will continue until the southwest fetch abates late. In addition, widely scattered showers and thunderstorms are possible until the front pushes offshore. Previous discussion...Southwest flow will continue through the evening between high pressure offshore and a cold front approaching the coast. The front will move offshore after midnight along with the associated shift to northerly winds. Significant seas will remain in a 3-4 foot range with some five foot seas building into the outer waters late this afternoon and evening ahead of the front. Scattered showers and a few thunderstorms will be possible this evening before frontal passage. Winds will shift to north-northeast by 2-4 AM as high pressure builds over the waters from the northwest. After a post-frontal surge to 15-20 knots, winds are expected to fall off to 10 knots by Thursday afternoon. SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/... As of 230 PM Wednesday...High pressure will move eastward across the Mid-Atlantic states Thursday night, then offshore Friday. A northeasterly wind direction should dominate through the period. Models have been quite consistent over the past couple of days with the strength of this wind, expected to peak Thursday night into Friday morning at 15-20 kt. This should create a very choppy 3 foot wind wave, with combined seas building to around 4 feet, perhaps locally 5 feet in the Frying Pan Shoals vicinity. Winds should begin to diminish Friday afternoon and particularly Friday night. Although mainly dry weather is expected, Scattered showers could begin developing across the Gulf Stream Thursday night, pushing southwestward and perhaps impacting the outer portions of the coastal waters at times. This will become more likely by Friday night as steering winds above the surface veer more easterly and a weak inverted trough approaches from the Gulf Stream off the Georgia and South Carolina coast. LONG TERM /SATURDAY THROUGH MONDAY/... As of 230 PM Wednesday...Surface ridge axis across the western Carolina with a weak trough just offshore will maintain northeasterly flow at the onset Saturday. The trough will push onshore and weaken during Saturday allowing weak onshore flow to develop later in the day. Light southerly winds will prevail Sunday and Monday with high pressure east of the waters. Seas will be 3-4 across the outer waters early Saturday then subside to around 2 ft by Saturday night. 2 footers will persist into Sunday and Monday given the weak flow and lack of swells. Widely scattered showers and tstms possible at times Sat-Mon. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...None. && $$ NEAR TERM...CRM SHORT TERM...TRA LONG TERM...SRP AVIATION...43
Area Forecast Discussion
National Weather Service Jacksonville FL
940 PM EDT Wed Aug 22 2018 .UPDATE...A swath of moisture ahead of a cold front and being enhanced by an upper level short wave trough was producing persistent bands of heavy showers with isolated thunder across Ne Fl this eve. Due to loss of heating no strong storms are expected although isolated rainfall amounts of over 2 inches will be possible the next few hours. High-res HRRR showing this activity gradually weakening and pushing Se as the cold front moves across the area ushering In drier air and the upper short wave lifts out. && .AVIATION...A cold front pushing Se towards the terminals will produce scattered storms mainly this eve with activity ending after midnight. Have VCTS with ocnl TSRA and IFR at JAX til 02Z. Have VCTS with ocnl TSRA and MVFR at VQQ til 03Z. Have VCTS at CRG til 03Z. Currently have VCSH at GNV and SGJ til 02Z-03Z although SGJ may need an amendment for possible TSRA. && .MARINE...SSW winds have increased to 15 knots offshore and these winds expected to gradually decrease and become west to northwest by later tonight as a cold front moves across the waters. Isolated showers and storms will be moving mainly offshore the Ne Fl waters and may produce strong and gusty winds in addition to lightning. Rip Currents: Moderate risk expected Thursday. && .PRELIMINARY POINT TEMPS/POPS... AMG 72 90 73 88 / 10 20 20 40 SSI 76 89 76 85 / 10 30 40 50 JAX 74 92 74 92 / 40 30 30 40 SGJ 74 89 74 87 / 40 20 40 40 GNV 73 92 73 91 / 30 30 30 40 OCF 73 93 73 91 / 30 30 30 50 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. && $$ PP/ACS/KB
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
916 PM EDT Wed Aug 22 2018 .SYNOPSIS... A cold front over the middle of the state will move through eastern NC tonight and off the coast early Thursday. High pressure will build in from the north Thursday and Friday, and by early next week will then extend into the region from the western Atlantic. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... As of 915 PM Wed...Convection remains rather limited over the region as front approaches the coast. HRRR shows some increase in cvrg next few hrs near cst poss where convergence is enhanced with remnants of sea breeze. Will cont lower chc pops inland next cpl hrs with higher chc imd cst thru 06 to 07Z. Precip still expected to be mainly offshore by daybreak. Prev disc...Looking at another 12 hours of active weather followed by a prolonged period of mostly benign weather beginning Thursday. Continued deep cyclonic flow through this evening with an advancing cold front. The mid level trough and associated vorticity will move through the area this evening and produce scattered showers and thunderstorms. Dewpoints in the lower to mid 70s and highs around 90 have produced MUCAPE values around 3000 J/kg. The moderate instability combined with 0-6 km shear around 25 kt will contribute to potential storm organization leading to a low end severe weather risk for isolated damaging winds. Locally heavy rains will also occur in the strongest storms. Rain threat will end after midnight from west to east as the cold front moves off of the coast 4-5 AM. Drier air will sweep into the area in the northerly flow behind the front. Lows will range from the upper 60s coastal plain to the lower 70s south coast and mid 70s Outer Banks. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... As of 345 PM Wed...Drier, cooler and less humid conditions are expected Thursday as northerly flow prevails in the wake of the cold front. High pressure will build into the area from the north producing mostly sunny skies with highs in the lower 80s. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... As of 345 PM Wed...Drier/cooler airmass will prevail across the region Thursday night and Friday. Temperatures are then forecast to moderate into the mid 80s over the weekend and upper 80s to around 90 early next week in response to a building upper ridge resulting a more typical summer surface pressure pattern with high pressure extending inland from the Western Atlantic and a Piedmont trough. Precipitation chances are still looking below normal through early next week with a mainly diurnally driven pattern beginning over the weekend with isolated sea breeze activity inland in the afternoons/early evenings and very small overnight chances near the coast. Thursday night and Friday...The coolest air of the summer season arrives by Thu night with clear skies and light winds resulting in lows well inland dropping into the upper 50s with low 60s closer to the coast with comfortable mid to upper 60s beaches. Continued dry Fri with highs in the low 80s. Saturday through mid next week...A weak pressure gradient over the weekend will promote local sea breeze circulations to develop and move inland with an isolated shower or storm possible. As the more traditional surface pattern redevelops Sunday and early next week, PWATs gradually increase but with little to no forcing aloft, precipitation chances will remain very low. The main affect will be a return to summer heat and humidity values. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... Short Term /through Thursday/... As of 615 PM Wed...VFR shld cont to dominate. Sct convection along and ahead of front could lead to brief sub VFR and gusty winds thru evening. Drier air will spread in behind front later tonight ending convective threat. VFR cigs shld grad sct out later tonight with mclr skies expected Thu as much drier air moves in behind the cold front. WSW winds this evening ahead of front will become N later tonight into Thu as front moves offshore. Long Term /Thu night through Mon/... As of 345 PM Wed...VFR conditions will prevail through the TAF period as high pressure influences the weather over the area and limits the precipitation potential through early next week. && .MARINE... Short Term /through Thursday/... As of 915 PM Wed...As front approaches cst stronger SW winds beginning to shift E with highest winds outer central wtrs currently. Will drop SCA Pamlico Sound and srn wtrs and keep a few more hrs central wtrs. Prev disc...Moderate SW flow will continue through this evening ahead of the advancing cold front. Winds will continue 15-25 knots and gusty ahead of the front with 4-6 ft seas over the outer central/southern waters, and 10-20 knots and 3-4 ft seas elsewhere. Behind the front winds will shift to the North 15-20 kt late tonight and Thu with seas 3-5 ft expected. Long Term /Thu night through Mon/... As of 345 PM Wed...NE-E flow 10-15 kt is forecast Thu night through Sat with 3-4 ft seas through Fri night subsiding to 2-3 ft Sat. L/V winds Sun 10 kt or less are expected to become S 10 kt or less Mon with seas around 2 ft both days. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...Small Craft Advisory until 1 AM EDT Thursday for AMZ152-154- 156. && $$ SYNOPSIS...JME/HSA NEAR TERM...RF/JME SHORT TERM...JME LONG TERM...JME/BM AVIATION...RF/BM MARINE...RF/JME/BM
Area Forecast Discussion
National Weather Service San Francisco Bay Area
831 PM PDT Wed Aug 22 2018 .SYNOPSIS...Temperatures are forecast to remain near seasonal averages, or cooler than average, through the rest of the week, into the weekend, and well into next week. Widespread night and morning low clouds will continue with only partial afternoon clearing expected in coastal areas. && .DISCUSSION...As of 8:30 PM PDT Wednesday...The marine layer deepened to about 3000 feet today, deep enough to mix out for a time and allow for earlier clearing. Earlier clearing today resulted in modest warming across most of our region. Even so, today`s high temperatures remained slightly below seasonal averages, especially for inland areas. Current satellite shows that low clouds are not as widespread this evening compared to last evening at the same time. However, low clouds are expected to become widespread overnight as the boundary layer cools. Since the marine layer is expected to remain deep, look for widespread low clouds to develop inland once again by Thursday morning. Indications are that Thursday will be a day much like today, with clouds clearing in most inland locations by midday, and with partial afternoon clearing at the coast. Temperatures will remain mild and generally slightly cooler than normal. Sea surface temperatures along our coast have been trending warmer lately due to lack of significant upwelling. This has had an impact on our weather by keeping overnight temperatures elevated to some extent, especially near the coast and in the coastal valleys. A forecast update was completed earlier this evening to increase overnight lows tonight and Thursday night. The update also included adjusting tomorrow`s highs to bring them more in line with persistence. A shortwave trough near the coast of British Columbia is forecast to drop southeast and into the Pacific Northwest by late Thursday. This trough is not forecast to deepen sufficiently into northern California to have much impact on our weather. Thus, only minor day to day changes are anticipated through Saturday. A second, colder, trough is forecast to drop south out of British Columbia and deepen across northern and central California late in the weekend and into the first part of next week. This will likely result in inland cooling early next week, with model guidance forecasting inland temperatures to drop as much as 10 degrees below normal by Monday. This trough may be cool enough to mix out the marine layer which would mean more sun in coastal areas and thus little or no cooling there. The longer range models keep the longwave trough position anchored across the West throughout next week, which should mean continued mild temperatures inland through the end of August. && of 4:50 PM PDT Wednesday...Stratus has cleared out of the terminals as METARS are reporting CLR to FEW clouds. Satellite image shows stratocumulus clouds forming over the SF Peninsula and just north of SNS and MRY. These clouds are seen to be expanding and will bring an early return of cigs to SFO and the MRY Bay Area terminals. This morning`s run of the HRRR smoke model shows vertically integrated smoke increasing across the entire area starting tonight. Vicinity of KSFO...MVFR cigs returning by 04Z. West winds to 15 kt through 04Z. SFO Bridge Approach...Similar to KSFO. Monterey Bay Terminals...MVFR cigs after 01Z at MRY and 02Z at SNS. && of 04:45 PM PDT Wednesday...Light winds will persist over the coastal waters through tomorrow with locally breezy winds possible near coastal gaps in the afternoon and evening. A broad area of high pressure over the eastern Pacific interacting with a strengthening trough over inland California will cause northwesterly winds to increase, mainly over the northern outer waters, starting Friday. Northwest swell will remain generally light through the period along with a weak southerly swell. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tngt...None. $$ PUBLIC FORECAST: Dykema AVIATION: W Pi MARINE: AS Visit us at Follow us on Facebook, Twitter, and YouTube at:
Area Forecast Discussion
National Weather Service Pueblo CO
259 PM MDT Wed Aug 22 2018 .SHORT TERM...(This evening through Thursday) Issued at 259 PM MDT Wed Aug 22 2018 Clouds have been slow to break across southeast CO with portions of El Paso, Kiowa and Prowers counties staying under clouds well into the afternoon. Limited surface heating has resulted in limited instability for these areas...and a few showers that have moved off the higher terrain of Teller county into the El Paso county have diminished. With dew points in the 50s and lower 60s across the plains and banked up into the southeast...where sufficient heating does occur, models suggest MLCAPE values of 1000-2000 j/kg. Deep layer shears are running 30-40 kts where surface winds are more locations along/north of the surface boundary will see the best chance for strong to severe thunderstorms this afternoon and evening. This will run along and east of I-25, and along and south of highway 50. This is where HRRR seems to be converging on the stronger convection through the evening hours. Large hail and damaging winds will be the primary risks for these areas. Low level jet cranks up tonight and this will lead to a cluster of thunderstorms across southeast plains into the overnight which will shift eastward into KS after midnight. Thursday will be a drier day as the upper trof over the northern U.S. Rockies moves eastward across WY into the Central Plains. This shifts the surface flow more westerly and helps dry out surface dew points. There will still be some lift along the tail end of that feature as it shears out across northern CO during the another round of thunderstorms will fire up across the mountains which will move eastward into the adjacent plains. With lower dew points across the area, storms will be weaker and less widespread though gusty winds and lightning will be the primary threats. -KT .LONG TERM...(Thursday night through Wednesday) Issued at 259 PM MDT Wed Aug 22 2018 Thursday night-Friday night...Northwest flow aloft moderates Thursday night and becomes more westerly through Friday night, as a passing upper trough across the Northern High Plains continues to translate east of the area, and upper level ridging builds back across the Great Basin and into the Rockies. Models remain in good agreement of much drier and subsident air working into the region Thursday night and Friday, with breezy west to northwest flow helping to dry the lower levels of the atmosphere. With that said, models indicating only isolated afternoon and evening showers possible, with best coverage across the Southern Mountains. With the drier air working into the region, overnight lows could be on the cool side, with the potential for strong radiational cooling, with highs expected to warm back to at and above seasonal levels in the mid 80s to mid 90s across the lower elevations, and mainly in the 60s and 70s across the higher terrain. Saturday-Wednesday...No big changes to current extended forecast, as west to southwest flow aloft progged across the region for the weekend and into early next week, as more energy translates across the Pac Northwest and pushes the upper high pressure across the Southern High Plains. This will open the door for more monsoonal moisture to spread back across the Rockies, with the best available moisture remaining along and west of the ContDvd. Models do indicate a deeper upper trough digging across the Great Basin through the middle of next week, though differ on it movement across the Rockies. At any rate, will keep current isolated to scattered afternoon and evening storms over and near the higher terrain through the period. Temperatures look to remain at and above seasonal levels, with highs in the mid 80s to mid 90s across the lower elevations, and mainly in the 60s and 70s across the higher terrain. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 259 PM MDT Wed Aug 22 2018 VFR conditions expected at the terminals this afternoon with -TSRA developing over the mountains and moving off into the adjacent plains. These may produce brief MVFR conditions if they impact the terminals due to lowered CIGS and restricted VIS. Thunderstorms will pull east of the terminals by 01-02z. There may be another window of VFR to MVFR cigs for both KCOS and KPUB from 05z to 10z. Beyond 10z west to northwest winds should help erode the cloud deck eastward with VFR conditions expected Thursday morning. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KT LONG TERM...MW AVIATION...KT
Area Forecast Discussion
National Weather Service Topeka KS
940 PM CDT Wed Aug 22 2018 .UPDATE... Issued at 940 PM CDT Wed Aug 22 2018 With storms struggling to materialize in western Kansas in satellite/radar data, have trimmed back PoPs more in line with the 12Z HREF/00Z HRRR & RAP, bringing the band of precip into the western CWA starting at 06Z and reaching Topeka by 10Z. These showers should be fueled by increasing 900-800 mb theta-e advection through the morning as shown by all of the deterministic models--thus confidence in their development is still high attm. MUCAPE values of 500 J/kg and minimal effective shear should minimize thunderstorm coverage. && .SHORT TERM...(This evening through Thursday) Issued at 255 PM CDT Wed Aug 22 2018 Several minor perturbations were noted on water vapor imagery rounding the upper ridge across the region. Isolated showers earlier this morning have since dissipated while elevated showers and isolated thunderstorms persist over southern Kansas. I left a slight chance for showers to impact north central Kansas through early evening, however confidence is low based on low level dry air advecting southward into the area. For tonight, low level upslope flow increases over the higher terrain of western Kansas. A strong, 40 kt low level jet develops overnight, increasing the likelihood of sustaining convection as it migrates eastward into the CWA in the 06-12Z time frame. Mid level instability is very limited despite bulk shear values in upwards of 30 kts. While I cannot rule out isolated, morning thunderstorms, the overall severe risk is low through Thursday morning. With rainfall probabilities being likely to definite, forecast rainfall amounts close to 1 inch will be common throughout the area. Focus for the forecast is on Thursday into the evening hours as the strong upper trough lifts out into the northern plains. The potential for severe storms still hinges on lingering morning showers and how long they persist. Current short term guidance indicates scattered showers through early afternoon with some clearing occurring across portions of central and north central Kansas. Meanwhile, sfc lee cyclogenesis occurs in advance of a west to east oriented warm front near and just north of interstate 70 by late afternoon. The latest GFS and ECMWF solutions are hinting at convection forming near and just north of the boundary in northeast Kansas by 00Z. The latest NAM and wrf solutions depict similar scenarios but have the boundary centered closer to the I-70 corridor. A deterrent to the sfc based convection however in central Kansas would be the increasing h85 temps and low level inversion layer. Regardless, if storms are able to overcome the inversion layer, ample instability and shear values in excess of 40 kts would support supercells capable of large hail, damaging wind gusts, and perhaps an isolated tornado given the low level helicity values depicted in forecast hodographs. Overall, will continue to monitor showers overnight to determine how the mesoscale details with play out with late afternoon thunderstorms. .LONG TERM...(Thursday night through Wednesday) Issued at 255 PM CDT Wed Aug 22 2018 Scattered convection remains likely through the first half Thursday night as the upper trough gradually moves into the Great Lakes region Friday. A subsident airmass builds in behind a weakening frontal boundary over the area while strong h85 winds advect +20C temps into northeast Kansas Friday through the middle of next week. Meanwhile mean flow aloft transitions towards the southwest, with weak perturbations translating through bringing occasional slight chances for precipitation Saturday night through Wednesday. Coverage is focused towards north central areas during this time. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 650 PM CDT Wed Aug 22 2018 Ceilings gradually lower to MVFR and IFR levels from west to east between 09 and 15Z tomorrow as a band of showers and isolated thunderstorms move through. Ceilings should improve in the afternoon as this band pushes out, but additional showers and storms may redevelop Thursday afternoon and evening throughout NE Kansas. Winds will veer from the east to the SSE by Thursday morning at 5 to 10 kts with some higher gusts behind the departing morning showers. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Skow SHORT TERM...Prieto LONG TERM...Prieto AVIATION...Skow