Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/09/17


Area Forecast Discussion
National Weather Service Bismarck ND
1011 PM CDT Thu Jun 8 2017 .UPDATE... Issued at 1002 PM CDT Thu Jun 8 2017 Again no change for the overnight. Continuing to assess the convective potential for Friday. The 18 and 21 UTC ESRL HRRR and the 21 UTC SREF calibrated severe probabilities signal a growing threat for organized convection propagating out of Montana late Friday evening and into the overnight. While moisture will be less, uncertainty in how overturned the airmass will be from the afternoon suggests that storms associated with stronger forcing and supported by strong shear could posed a continued severe threat into the night. UPDATE Issued at 632 PM CDT Thu Jun 8 2017 No change for tonight other than to blend to observed trends through 23 UTC. Did increase winds to the max of forecast guidance for Friday, especially for central North Dakota with deep mixing and pressure falls ahead of the surface trough. && .SHORT TERM...(This evening through Friday) Issued at 303 PM CDT Thu Jun 8 2017 The main concerns in the short term period will be the chance of thunderstorms (some possibly severe Friday) and hot temperatures. Short term models have generally kept their scenario of a wave riding over the H5 ridge tonight into Friday. This brings a chance of thunderstorms to mainly northwest parts of the state late tonight, that spread south and east Friday. There are still differing ideas regarding how far south the thunderstorm potential will exist Friday with solutions generally favoring the higher chances in the northern parts of the forecast area. Forecast soundings do show a decent cap early in the day, especially south, but there are hints that it could erode by mid to late afternoon. The updated day 2 Severe Weather Outlook from the Storm Prediction Center spread the slight risk a little farther south and west which appears reasonable. Sounding analogs for tomorrow support a potential very large hail scenario while low level (0-1km) shear is best towards the Turtle Mountains, so we will have to see if that remains consistent in later model runs. The other concern for Friday will be the hot temperatures. The current forecast was based on the maximum temperatures output from the models and have started with that again for this forecast. There is some concern that convective cloud debris, especially in the north, could hold temperatures back from reaching their full potential, so shaved a few degrees off highs in that area. .LONG TERM...(Friday night through Thursday) Issued at 303 PM CDT Thu Jun 8 2017 The initial round of thunderstorms should exit to the east Friday evening, but additional storms are possible closer to the passing frontal boundary in western parts of the state Friday night into Saturday morning. There could be a few thunderstorms near the North Dakota / South Dakota border Saturday night into early Sunday, but the better chances appear to arrive Monday into Monday night. A large H5 trough / low is expected to lift across the region, and the Storm Prediction Center has already placed a severe weather risk in parts of western North Dakota. The model blend carries at least a chance of rain across parts of the forecast area through the remainder of the extended period which doesn`t seem unreasonable as the area could still have influences from the departing low. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1002 PM CDT Thu Jun 8 2017 Low level wind shear is possible across much of western and central North Dakota late tonight into Friday morning with strong winds off the surface in an inversion. A surface trough of low pressure will move into western North Dakota Friday afternoon. Strong southeast winds of 25-35kts ahead of the trough will become westerly behind this feature. Scattered severe thunderstorms are possible late Friday afternoon and through the night. While coverage may be low, destructive hail and damaging winds are possible. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...PA SHORT TERM...CJS LONG TERM...CK AVIATION...PA
Area Forecast Discussion
National Weather Service Taunton MA
1048 PM EDT Thu Jun 8 2017 .SYNOPSIS... An ocean storm will brush Cape Cod and the Islands with a period of rain overnight. A trough of low pressure will trigger a few showers and isolated thunderstorms Friday afternoon, especially across northwest Massachusetts. Otherwise mainly dry seasonable weather is expected. A weak cold front may trigger a few more afternoon showers/isolated thunderstorms Saturday. Then the Bermuda High pumps summer heat and humidity into southern New England Sunday through Tuesday. A backdoor cold front breaks the heat with more seasonable weather and lower humidity Wed and Thu of next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 1030 PM Update... Mid and high deck of clouds as seen on latest IR satellite imagery and OBS this evening will continue to lower and thicken, mainly across central and eastern areas overnight. Leading edge of rain approaching the southern islands at 02Z, moving steadily N-NE as seen on latest KBOX 88D radar. Noting rather wide T/Td spreads though, so may take a bit of time for precip to reach the ground. High res near term models continue to signal steadiest precip remaining across E Mass overnight into early Friday morning. Forecast QPF amounts remain highest across Cape Cod and the islands, with 0.5 to 0.8 inches, possibly a bit higher on Nantucket. Expect NE winds to increase overnight across the Cape and islands as well, with gusts up to 25-30 kt from KPVC to KACK. Have updated near term forecast to reflect current thinking, with minor changes noted through the overnight. Previous Discussion... Models continue to be in agreement of keeping the center of the emerging low pressure system southeast of the 40N/70W benchmark. For the 12Z guidance, not much difference in placement of the low track, also keeping the deeper moisture offshore. 12Z GFS/NAM/ECMWF confine precip to southeast MA. However, HRRR is showing the potential for light QPF amounts as far N as BOS, and as far W as RI. So at this time, plan to continue the chance pops for light rain PVD-BOS and southeast MA. Highest likelihood of measurable rainfall exists across the Cape and Islands, especially Nantucket, where likely to categorical pops are in place. Winds will be strongest on the outer Cape and Nantucket late tonight into Friday morning, with gusts 25 to around 30 kt. Wind gusts should drop off considerably NW of the Cape Cod Canal. Overnight lows mainly in the low 50s. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... Friday... Offshore low center passes well east of southern New England on Friday. The western periphery of the precipitation from this low may reach into east coastal MA for part of the morning, ending by midday. However, that will not mean the end of precipitation for the day within southern New England. A short wave and surface trough move into the area during the day, and these features could serve as triggers for some showers. Low level lapse rates become steep across the interior during the afternoon. NAM indicates better chance for some t-storms than the GFS, which indicates a mid level cap may limit extent of convection. So at this time will not go higher than a chance pop and mention isolated thunder possible. Expect temps to be a bit cooler than this past afternoon, with highs in the 70s except 60s to near 70 along the immediate coast. Friday Night... Short wave moves east of the area with some weak surface ridging. Any lingering diurnal convection should end early, with dry conditions for the overnight. Mainly clear skies with lows in the mid and upper 50s. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Highlights... * Heat wave likely Sun-Mon-Tue * Backdoor cold front breaks the heat Tue ngt/Wed * More seasonable and less humid Wed/Thu next week Synoptic Overview & Model preferences... Last short wave trough rotates through the northeast long wave trough Saturday, albeit of fairly low amplitude. By Sunday the subtropical ridge builds into the Mid Atlc region resulting in summer heat and humidity advecting into southern New England Sunday thru Tuesday. Good agreement among both EC & GFS ensembles on anomalous airmass advecting into southern New England with 850 mb temps of +18C Sun-Mon-Tue. In addition 925 mb temps from ensembles also support 90+ surface temps with +24C all three days at 925 mb. As expected hi res deterministic guidance even warmer with +20C at 850 mb and +26C at 925 mb, toasty! However later in the forecast period models do differ on the timing of a backdoor cold front, which will be critical in determining the duration of this potential heat wave. All model guidance including the 00z GEFS/ECENS along with the 12z UKMET/ECMWF support a slower fropa of Tue ngt/Wed. The exception is the 12z GFS which simulates a fropa sometime Tue. While the 12z GFS solution is possible, at this time range prefer to lean towards model consensus with a fropa of Tue ngt/Wed. Daily Details... Saturday... Mid level lapse rates are not impressive at less than 6C/KM in response to H5 temps only -14C (compared to -18C Fri aftn) and warming late in the day. In addition mid level short wave is of fairly low amplitude so only offering weak cyclonic flow aloft. So given weak forcing for ascent combined with weak instability, may only be looking at showers with any thunder very isolated. Otherwise a fairly nice day by Jun standards with highs in the upper 70s to low 80s, cooler south coast given SSW surface winds. Comfortable humidity with dew pts in the 50s. Morning sunshine will give way to afternoon clouds as mid level trough moves thru the region. Sunday/Monday and Tuesday... Subtropical ridge builds into the Mid Atlc this period resulting in the likelihood of a 3 day heat wave with highs well into the 90s away from the south coast. Sunday will be breezy as gradient tightens. This will help take some of the edge off the hot temperatures. Given temp anomalies at 925 mb and 850 mb are projected to run +2 standard deviations warmer (+24C to +26C at 925 mb and +18C to +20C at 850 mb) than climo highs may climb into the mid and upper 90s each day! Thus added 2-4 degs to guidance each day and that may still be too cool. Later shifts may need to go even warmer than guidance. Mainly dry weather as well with the exception of Tue with a low risk of convection ahead of backdoor cold front. It will be humid too with dew pts in the 60s. Wednesday and Thursday... Heat wave breaks and is replaced by much more seasonable airmass with highs in the 70s and lows in the 50s as Canadian high pressure builds southward from Quebec. Coolest temps across eastern MA and warmest weather in the CT River Valley. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Friday Night/... 1030 PM Update... Overnight...Moderate confidence. Conditions will lower to MVFR-IFR across Cape Cod and the islands with areas of rain and patchy fog moving thru that area. Elsewhere, mainly VFR. Chance for rain late tonight, probably 07z to 10z, as far west as BOS-PVD. N-NE wind gusts up to 20-30 kt across mid and outer Cape and islands after midnight. Friday...Moderate confidence. Any MVFR-IFR conditions across the Cape and islands should improve to VFR though showers may linger. Will see scattered showers across the region as upper level disturbance moves across. Isolated thunderstorms possible mainly across central and western areas, but isolated thunder could reach as far east coastal MA late in the day. N wind gusts up to 25-30 kt through midday across the Cape and islands. Friday night...High confidence. VFR. KBOS TAF...High confidence in TAF, except there is a low chance of a period of sea breeze conditions Friday morning. This is not reflected at this time in the TAF but a low possibility that needs to be monitored. Otherwise, may get a trace of rain with probably a 30 percent chance or less of measure during early morning hours. KBDL TAF...High confidence in TAF. Outlook /Saturday through Tuesday/...Moderate confidence. VFR much of the day. Only minor issue will be marginal MVFR-VFR Sat afternoon in widely scattered showers/isolated Thunder. Winds only an issue Sunday afternoon with WSW winds gusting up to 25 kt possible. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Friday Night/... Overnight...Moderate confidence. Expect E winds to back to NE and increase after midnight. Gusts up to 25-30 kt expected mainly across Nantucket Sound and the southern outer waters to E and S of Cape Cod and Nantucket. Seas will also build to around 5-7 ft, up to 8 ft E of Cape Cod toward daybreak. Visibility restrictions overnight in areas of rain and patchy fog. Small crafts remain in effect for later tonight for most of the open waters. Friday...Moderate confidence. Winds shift to N-NW with gusts up to 25-30 kt on the eastern outer waters as well as Nantucket Sound and Cape Cod Bay Fri morning, then diminishing. Seas on the outer coastal waters and RI/BI Sounds remain at 5-7 ft thru the day. Showers linger in the morning with local visibility restrictions. Friday night...Moderate confidence. SW winds 20 knots or less. Seas will be 5 to 7 feet on the outer waters and exposed southern waters Friday night, gradually subsiding. Outlook /Saturday through Tuesday/... Saturday... Isolated T-storm possible in the afternoon near shore. Sunday... WSW winds may gusts up to 25 kt near shore. Mon and Tue... modest WSW winds. Dramatic wind shift from WNW Tue to NE sometime Tue night into Wed. && .CLIMATE... Here are the record highs for Sun (6-11), Mon (6-12) and Tue (6-13) of next week. ...BOS... ...PVD... ...ORH... ...BDL... 6/11...98/1954...95/1873...91/1984...98/1973 6/12...96/1973...94/1973...90/1973...97/1973 6/13...98/1984...94/1956...92/1984...96/1984 && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory from 3 AM to 2 PM EDT Friday for ANZ232. Small Craft Advisory from 7 AM to 1 PM EDT Friday for ANZ231. Small Craft Advisory from 6 AM Friday to 4 AM EDT Saturday for ANZ235-237. Small Craft Advisory from 3 AM Friday to 3 AM EDT Saturday for ANZ250. Small Craft Advisory until 6 AM EDT Saturday for ANZ254-255. Small Craft Advisory until 6 AM EDT Saturday for ANZ256. && $$ SYNOPSIS...Nocera/NMB NEAR TERM...EVT/Thompson SHORT TERM...NMB LONG TERM...Nocera AVIATION...Nocera/EVT/Thompson MARINE...Nocera/EVT/Thompson CLIMATE...Staff
Area Forecast Discussion
National Weather Service Grand Rapids MI
1003 PM EDT Thu Jun 8 2017 LATEST UPDATE... Update .SYNOPSIS... Issued at 320 PM EDT Thu Jun 8 2017 Some showers will likely move into the region early Friday before exiting the area. Additional showers and a few thunderstorms may develop Friday afternoon particularly east of US 131. A warm up is expected this weekend into early next week with highs well into the 80s and perhaps some 90s making their first appearance this year. Some thunderstorms may impact central and northern Lower Michigan at times with this pattern taking shape. && .UPDATE... Issued at 1003 PM EDT Thu Jun 8 2017 Will limit the mention of thunder (slgt chc) tonight to just the NW portion of the CWFA including Ludington/Muskegon - only through 06z. RAP guidance has 200-400 J/KG of MUCape in this region through 06z and there are some storms upstream over NE WI. Otherwise mostly cloudy (or becoming mostly cloudy east of hwy 131) with isolated to scattered light rain showers. The 00z soundings at DTX and APX are very dry so measurable pcpn may be difficult to come by through 12z. Much of this will probably just be sprinkles/virga. && .SHORT TERM...(This evening through Saturday night) Issued at 320 PM EDT Thu Jun 8 2017 The primary forecast challenge is determining rain chances tonight into Friday and whether portions of Lower Michigan may get clipped by any storms late Saturday night into Sunday morning. GOES-16 mid level water vapor imagery this afternoon is resolving the H500 shortwave trough across Lake Superior, which will move southeast tonight and help draw a 25-30 kt LLJ core over southern Lake Michigan between 00z and 06z. A weak surface low is forecast to cross northern Lake Michigan during that time. H500-H850 RH is shown to increase to 80%-90% over western Lower Michigan by 06z as PW values climb to 1.00"-1.20". There should be at least some showers moving through western Lower especially from 06z-12z. MUCAPE barely registers above zero, so thunderstorms are not likely, but a slight chance mention is still prudent. After the Friday morning showers press east into central and south central Lower MI, daytime instability should recover. SBCAPE will likely exceed 1000 J/kg by 18z near and east of US 131. Also, upper level support arrives by this time coincident with the surface low moving through. The ULJ core should be about 80 kts as it noses into central Lower. The best upper level divergence is shown to occur across this region as well as eastern Lower. This is the favored region for afternoon shower and thunderstorm activity. Deep layer shear is only 25-30 kts, not very good for organized, strong convection. Still, SBCAPE coupled with LI values of -2 to -4 would support some storms, given the other factors mentioned. I`m thinking the westerly H850 and surface flow off Lake Michigan during the day should create a dry buffer zone for much of the lake shore region extending toward US 131, but will maintain a small risk for rain there. After a dry and breezy Saturday, the first in a series of ridge rider MCSs is likely to develop across the Midwest Saturday night. While the upper level forcing will clearly reside across Upper Michigan and Northern Lower, questions remain about whether ridge amplification will be sufficient enough to keep the MCS north of our region, and also whether elevated instability will tend to buckle southeast into our region from Wisconsin during the late night hours. The ECMWF, GFS, and GEM all show MUCAPE increasing across western Lower MI between 06z and 12z Sunday. MCSs tend to propagate toward the instability axis so we will have to monitor trends. Our latest forecast is featuring a 30% probability of storms making it into our lake shore region north of Whitehall by early Sunday morning. .LONG TERM...(Sunday through Thursday) Issued at 320 PM EDT Thu Jun 8 2017 Little question it will be warm and humid through at least Wednesday of this coming week. The best chance of meaningful rain (greater than the daily mean evaporation rate of .2 inch/day) would be Wednesday into Thursday. The big picture shows three large storms over the northern Pacific into extreme eastern Russia this morning. There is a large upper ridge over the western CONUS that has an extension that leans northwest across Alaska into northeast Russia. That ridge is on top of all of the systems over the north Pacific. The three systems track east over the next 3 days so that by Sunday we have a large but sort of flat ridge over the eastern CONUS with our 3 storms having moves east about about 20 degrees of longitude eastward. However by then we have ridge over western Canada across Alaska into eastern Russia north of those 3 storms. We also have a polar vortex looking circulation centered over northern Hudson Bay. Over time an omega block develops over the mid Pacific between those two more western storm systems while the system that moved into the western CONUS tries to shear out north of the Western Great Lakes (by Wednesday). Beyond that the models struggle with how to play out the omega block with those two western storm. What all of this does for Southwest Michigan is keep us in the warm humid air into Wednesday for sure. At some point, likely later Wed or Thursday we should see thunderstorms from the cold pool of air assoicated with the shearing out lead upper low. Since we do get that "polar vortex" looking system over Hudson by early next week, that will try to push a cold front into northern Michigan which could lead to some thunderstorms over our northern CWA early next week. Even so based on the 850 temps near 20c and 1000 to 850 thickness are near 1420, all of those tell me highs will be in the lower 90s so I am sticking with that. Beside our verification shows us running 4 to 6 degrees to cold for days 3-4-5-6 and 7 for the past 2 weeks. Bottom line warm and humid with thunderstorms later Wed into Thursday. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 757 PM EDT Thu Jun 8 2017 Cloud bases upstream are mostly above 8000 ft, so despite the scattered showers on radar heading this way will keep the TAFs VFR tonight and Friday. The air mass over lwr MI is currently quite dry with sfc RHs in the 20s and 30s, so much of what comes through should be light or just virga. Based on the latest RAP MUCape progs showing only a couple hundred joules at best, the threat of thunder is too low tonight and Friday morning to have any CBs in the TAFs. However, the threat of thunder is better on Friday afternoon east of GRR/BTL, so have included a mention of thunder/CBs at LAN and JXN after 16Z. && .MARINE... Issued at 320 PM EDT Thu Jun 8 2017 The first breezy day will be Saturday. Certainly could be some gusts to 30 kts over the open waters and perhaps the nearshore zones as well. This will create a rough chop on the lake especially north of Holland this weekend. Boaters should be aware of unfavorable conditions mainly Saturday afternoon and evening. && .HYDROLOGY... Issued at 1258 PM EDT Thu Jun 8 2017 River levels are around normal for this time of year, and much below bankfull. A little precipitation is possible tonight into Friday, with under a quarter of an inch expected. The next chance for rain doesn`t come until Tuesday night next week. Rivers may experience small rises, but no flooding is expected through next week. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...None. && $$ UPDATE...Meade SYNOPSIS...Hoving SHORT TERM...Hoving LONG TERM...WDM AVIATION...Meade HYDROLOGY...63 MARINE...Hoving
Area Forecast Discussion
National Weather Service Wichita KS
946 PM CDT Thu Jun 8 2017 .UPDATE... Issued at 945 PM CDT Thu Jun 8 2017 Weak mid level isentropic lift has led to some mid level cloud cover developing to the west and southwest of Wichita. Expect to see some increasing mid level clouds for portions of south Central and Central KS overnight, as weak isentropic lift continues through Fri morning. Latest RAP shows mid level warm advection and moisture transport over SW KS doesn`t really shift NE into south Central KS overnight, which will limit the chance of isolated elevated showers or storms developing late tonight or early Fri morning. So think the chances for Fri morning storms is diminishing. Latest hi-rez model solutions seem to support this decreasing storm chance, as the NAM/NNM is the only solution that shows any storm development over south Central KS for Fri morning. So will cut back on pop chances for areas west of I-135 through Fri morning. Will keep a small chance in, in case a stray storm can develop by sunrise on Fri. Ketcham && .SHORT TERM...(This evening through Sunday night) Issued at 208 PM CDT Thu Jun 8 2017 A remnant MCV in South Central Kansas is keeping some showers and thunderstorms going. This activity will slowly move to the east this afternoon and into the overnight hours. This moisture will be the only chance for precipitation tonight and early Friday. The forcing with this MCV will be replaced by a rather strong cap during the day Friday as a strong ridge move into the region. This will remove the rain chances from the forecast. The weekend looks hot and dry. Additionally, the pressure gradient will tighten up and will allow the winds to pick up. Saturday and especially Sunday look to be windiest days. Advisory winds are possible both days. .LONG TERM...(Monday through Thursday) Issued at 208 PM CDT Thu Jun 8 2017 A frontal system will be approaching the region Monday and Tuesday which will keep the pressure gradient rather tight. This will continue to keep winds on the brisk side for Monday and Tuesday. The strong southerly winds will also help keep hot temperatures in the mix with mid 90s possible. Moisture transport ahead of the next system will bring the needed moisture into the region and the front will provide the forcing. This will bring the chances for precipitation back into the forecast. This also raises the specter of severe weather as well as the conditions look favorable for some scattered severe thunderstorms Wednesday night. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 638 PM CDT Thu Jun 8 2017 VFR conditions are expected for the next 24 hours. There is a slight chance of some altocumulus and possibly some isolated VCTS near KRSL and KGBD from 09-12z/fri. So will add this mention to the tafs. Ketcham && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 62 88 69 92 / 20 20 0 0 Hutchinson 62 89 69 93 / 20 10 0 0 Newton 61 88 68 91 / 20 10 0 0 ElDorado 61 87 68 90 / 10 10 0 0 Winfield-KWLD 62 88 69 91 / 10 10 0 0 Russell 62 91 69 96 / 30 10 0 0 Great Bend 62 90 68 95 / 30 10 0 0 Salina 62 90 70 95 / 20 10 0 0 McPherson 61 89 69 93 / 20 10 0 0 Coffeyville 59 85 66 88 / 0 0 0 0 Chanute 59 86 66 88 / 0 0 0 0 Iola 59 86 66 88 / 0 0 0 0 Parsons-KPPF 59 86 66 88 / 0 0 0 0 && .ICT WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...BDK SHORT TERM...ELM LONG TERM...ELM AVIATION...Ketcham
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1002 PM EDT Thu Jun 8 2017 .UPDATE... Issued at 1002 PM EDT THU JUN 8 2017 Thunder chances have exited eastern Kentucky this evening, with only isolated showers possible across eastern Pike County prior to midnight. Increased fog wording a bit to account for clearing trends as high pressure builds into eastern Kentucky. UPDATE Issued at 828 PM EDT THU JUN 8 2017 Showers continue to wind down across far eastern Kentucky as the well-advertised upper trough pulls east. High pressure nudging into eastern kentucky from the west will lead to clearing skies this evening and tonight, thus promoting fog development tonight into Friday morning. && .SHORT TERM...(This evening through Friday night) Issued at 330 PM EDT THU JUN 8 2017 Surface analysis shows high pressure to our east and east surface trough nearby. Overall most locations remain dry this afternoon, but a few showers and thunderstorms have developed along and near the high terrain of SE KY. Therefore, concentrated overall better POP coverage in these locations with slight chances further west. Right now prefer the HRRR TL in general for coverage is expresses compared to other CAMs. Otherwise clouds will begin to lessen in coverage through the night for most, and this will lead to potential for fog overnight especially in areas that get added moisture from showers and thunderstorms and nearer bodies of water. There will also be a potential for some temperature splits. An area of surface high pressure will progress east along with height rises as upper level trough finally moves east to round out the short term. This will lead to a dry stretch, with clearing skies (besides afternoon CU) and warming temperatures through the remainder of the period. That said, temperatures will creep back up to near normal for Friday. .LONG TERM...(Saturday through Thursday) Issued at 330 PM EDT THU JUN 8 2017 Models are in good agreement with the mid and upper level pattern through the bulk of the period. Ridging will build across the eastern half of the CONUS and remain in place until late in the period, Dys 6-7, when energy associated with an Intermountain West low pressure system will begin to move into the Ohio Valley while the parent low tracks into central Canada. The 12Z GFS and Canadian do bring a bit more "troughiness" into the region by late Wednesday, but the 0Z ECMWF holds off on that energy until Thursday. This weak shortwave energy also appears strong enough to erode the strong cap in place over our area by late Wednesday and/or Thursday. At the surface high pressure remains solidly dug in and centered roughly over the southern Appalachians. As a result a surface cold frontal boundary barely manages to push through the Upper Midwest by Thursday before stalling out well to our northwest. Sensible weather looks dry and quite warm in general, with humidities on the increase as well with time. Daily highs will run well into the mid 80s each day and possibly even flirt with some upper 80s to around 90 for a few locations. H850 temps do support such numbers, advertised to rise to around 18 degrees by Sunday and then level off thereafter. The ECMWF does run slightly cooler which is reflected in guidance. Increasing moisture will drive dew points into the mid 60s by Sunday/Monday, making the heat that much more uncomfortable. This will tend to keep overnight lows up, well into the 60s. With the weakening cap we can expect some isolated to possibly scattered, mainly afternoon and early evening showers and thunderstorms towards the end of the extended. At present convection appears to be more typical of a hit and miss summertime pattern. However, that may change should any shortwave energy be strong enough to help convection become a bit more organized. Bottom line, typical weather for meteorological summer and good prep for the approach of astronomical summer. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) ISSUED AT 828 PM EDT THU JUN 8 2017 Current VFR conditions will likely deteriorate after midnight through early-mid Friday morning as clearing skies lead to fog formation. Earliest and quickest clearing will be near SME/LOZ, but greater moisture content will be found farther east nearer to SJS. MVFR/IFR visibilities/ceilings look to be a good bet for all sites, with LIFR/VLIFR also possible at times through mid Friday morning. VFR conditions will return thereafter as northwest to southwest winds increase to near 5 knots. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GUSEMAN SHORT TERM...DJ LONG TERM...RAY AVIATION...GUSEMAN
Area Forecast Discussion
National Weather Service Melbourne FL
934 PM EDT Thu Jun 8 2017 .UPDATE... Tonight...A much more subdued pattern, with respect to convection, will be on tap as drier air aloft was working down into the central peninsula behind a shortwave trough lifting out to the northeast. 00z Tampa sounding had 1.1 inches of precipitable water, but Cape Canaveral was still around 1.5 inches due to more moist north to northeast flow. A weakening frontal boundary will stall and start to wash out over the area. Lingering widely scattered showers over southern sections ahead of the boundary were diminishing with loss of daytime heating. There have been a few Atlantic showers in the north/northeast flow, and the HRRR continues them overnight, but the onshore low level winds are forecast to weaken, so will not carry any coastal POPS. Weakly cyclonic low level flow, after a showery day, points to considerable low cloudiness. Guidance shows these clouds will be too dominant for any significant fog. Won`t be making any major changes. Plan to lower POPs over the north/central coastal waters. Friday...Surface boundary will stall/wash out over the area, bringing a gradient in moisture with drier air to the north and wetter to the south. Expect onshore flow behind the boundary to lead to a rather quick development of the sea breeze over northern and central areas, confining higher rain chances (still only around 30%) to inland areas. Deeper moisture across our southern zones (Okeechobee / Treasure Coast) should allow for a more active day there, so will maintain 40-50% PoPs. Expect a bit more sunshine once morning low clouds burn off, so it will feel warmer with mid to upper 80s coast and around 90 over the interior. && .AVIATION... Another round of IFR to low MVFR stratus is expected to develop overnight and continue into Friday morning. Higher moisture residing across our southern areas on Friday should lead to a higher chance for afternoon SHRA/TSRA across our Treasure Coast terminals (KVRB south) and points inland. More isolated activity expected to the north. && .MARINE... Tonight-Friday...Improved boating conditions Fri. Weak surface frontal boundary pushed down to about Stuart, but northerly winds were weak across the southern waters. The gradient was a little tighter in the central/north waters, supporting near 15 knots along with seas 4-6 feet, necessitating an Exercise Caution Statement. The gradient will weaken as the boundary starts to wash out and by Fri winds should be northeast around 10 knots in the north, and variable 5 to 10 knots in the south. Seas should run a little higher than normal for these wind speeds due to a northeast swell. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ FORECASTS...Lascody IMPACT WX...Blottman/Smith
Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
1058 PM CDT Thu Jun 8 2017 .SHORT TERM...(This evening through Friday) Issued at 315 PM CDT Thu Jun 8 2017 Dry weather expected for most locations across Minnesota and western Wisconsin today through Friday. Early afternoon satellite imagery together with surface obs and RAP analysis showed a weak boundary south of I-90 with some agitated cumulus and a few showers developing along it. There was another area of shallow convection across western Wisconsin. These two areas will be the focus for a slight chance for showers or an isolated thunderstorm later today. The frontal boundary across I- 90 will stall out and become north/south oriented as a warm front that will begin to push through the region on Friday. Based on the recent trends with temperatures, went on the high side of guidance once again. A few afternoon clouds will develop which will keep temperatures somewhat at bay. Afternoon storms will fire across far northern North Dakota, but these will remain well north of the northern part of the Twin Cities forecast area. .LONG TERM...(Friday night through Thursday) Issued at 315 PM CDT Thu Jun 8 2017 The longer term concerns remain heat/humidity especially Saturday over the far south Sunday and building again regionwide Monday and Tuesday ahead of the midweek cold front. The severe weather threat increase some to the far east Saturday night, with the main threat developing Sunday and again Tuesday into Wednesday. Saturday is expected to be windy and hot most areas ahead of the incoming cool front from the Dakotas. Most models drive this feature eastward, really bisecting the area NE-SW by Saturday evening. With the thermal ridge out ahead of the front we shouldn`thave much of a problem seeing 95 to 100F over much of the CWA especially with a gusty s-sw wind around 30 mph ahead of the boundary. Heat indices are forecast around 100 as well making for uncomfortable conditions. Mid level temperatures surge northeast across the cwa Saturday morning and is expected to retard any convection much of the day. There is a small chance of development on the northeast edge of the cap which is suppose to work slowly southeast Saturday night. We did retain small chance PoPs for this occurring over the eastern CWA. If convection did develop, severe weather parameters point to at least some chance of severe storms with hail and strong winds the main threat. This boundary is forecast to drive south along the MN/IA border by 12Z Sunday. If is forecast to lift north again Sunday into the central portion of the area by afternoon. A short wave is forecast to move across South Dakota Sunday morning and with very unstable conditions developing along and south of the front, severe convection will be a good bet. This along with potential heavy rain as well with PWATs nearing 2 inches by Sunday evening. Convection may develop early and just spread slowly east during the day into Sunday night. The boundary is forecast to lift north again Monday as southerly flow once again becomes established as the western CONUS trough spreads east. The thunder threat will continue to the north of the front. Hot and humid conditions will continue through Tuesday. There are some timing differences regarding the cold front for midweek, with the GFS a bit faster. Cooler temperatures/near normal follow this front for the rest of the period. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1058 PM CDT Thu Jun 8 2017 VFR conditions are expected through the period. Light north winds will become east overnight and then increase southeast Friday afternoon to 10-15 kt. KMSP...No additional concerns. /OUTLOOK FOR KMSP/ Sat...VFR. Wind SW at 25G35kt. Sun...VFR. TSRA likely, MVFR or lower possible. Wind E at 10kt. Mon...VFR. Chc TSRA. WInd SE at 5-10kt. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. && $$ SHORT TERM...JRB LONG TERM...DWE AVIATION...BORGHOFF
Area Forecast Discussion
National Weather Service Spokane WA
446 PM PDT Thu Jun 8 2017 .SYNOPSIS... Cool and showery weather will continue into the evening hours with a decreasing threat of precipitation overnight. Below average temperatures and scattered showers are expected Friday and Saturday. We should see a break in the showers on Sunday, but Monday has the potential for a widespread chilly rain for the Idaho Panhandle and portions of eastern Washington. && .DISCUSSION... Isolated thunderstorms were expanded into the Basin, Waterville Plateau, and southern portions of the Northern Mountains as well as the Spokane-Cd`A areas. Clearing behind the midday cold front and associated band of rain is resulting in areas of showers with embedded thunderstorms. HRRR is picking this activity up well and indicates it will track to the east for the next few hours. The main threats will be heavy downpours of rain and small hail which could result in gusty outflow winds on the order of 30-40 mph. /sb && .AVIATION... 00Z TAFS: A steady band of rain will continue to lift to the northeast out of NE WA and N ID through 02z. Clearing behind this wave has resulted in re-developing convection with isolated t-storms between KALW...KMWH...and KOMK. Brief heavy rain, small hail, and gusty outflow winds will be the main threats with these storms.. This second band of broken showers/storms will track east reaching the Spokane-Cd`A near 03z. Once this activity tracks east of the terminals, expect a threat for showers through the evening then becoming drier overnight. The moist boundary layer will result in patchy fog across the far northeastern valleys but light westerly winds suggest a low threat for any restrictions across the open Columbia Basin. Cumulus to build again Friday with afternoon heating with the main threat for showers in the Cascades and arnd Lewiston. /sb && .PRELIMINARY POINT TEMPS/POPS... Spokane 47 64 45 64 45 69 / 60 10 10 20 10 10 Coeur d`Alene 47 64 45 63 42 70 / 60 20 10 20 10 10 Pullman 46 62 44 60 43 65 / 80 30 30 30 10 30 Lewiston 51 67 48 67 47 69 / 90 40 60 40 10 50 Colville 47 66 45 66 44 73 / 60 20 20 50 20 10 Sandpoint 45 64 42 62 40 69 / 80 20 20 30 10 10 Kellogg 45 61 43 60 41 65 / 80 30 40 40 10 20 Moses Lake 46 70 46 70 46 75 / 60 10 10 20 10 10 Wenatchee 48 68 47 69 48 73 / 70 40 50 30 20 10 Omak 46 69 45 68 46 74 / 70 20 40 40 30 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion
National Weather Service Pueblo CO
318 PM MDT Thu Jun 8 2017 .SHORT TERM...(This evening through Friday) Issued at 249 PM MDT Thu Jun 8 2017 Tonight an upper ridge will be shifting eastward over the state the the axis expected to be about centered over CO by 12Z Fri. Then on Fri the ridge axis continues moving eastward over western KS by late in the afternoon. This afternoon, storms have been confined mostly over and near the eastern mountains and the southwest mountains, with just a few storms making it farther east over El Paso county. The NAM and HRRR forecast for this evening show this pattern continuing, with storms mainly focused over the Sangres and Wet mtns, and maybe over the plains south of highway 50. Will just go with some isolated POPs for the early evening hours acrs the plains, eastern mtns, southern San Luis Valley and the southwest mtns, then trending toward dry all areas by midnight. On Fri, drier air will be over the forecast area and will go with a dry forecast, along with warmer temps. Should see highs in the 90s across the plains, and in the 80s in the high valleys. .LONG TERM...(Friday night through Thursday) Issued at 249 PM MDT Thu Jun 8 2017 ...Drier and hotter into early next week... Expect a shift in the weather pattern through the weekend into early next week with hot and dry weather. While it may cool off a few degrees through the middle of next week, it will remain warm and dry. Models are in agreement with this pattern and ensemble spreads are generally small. Friday night through Monday...Friday night will remain dry with low temperatures around 60 across the plains and mid 40s in the mountain valleys. On Saturday, with the upper ridge axis shifted to our east and large upper low centered over the Pacific Northwest Coast, fairly strong southwest flow will prevail at the upper levels across Colorado. This flow regime will bring dry weather back to southern Colorado, with no precip expected on Saturday. The strong flow aloft will mix down to the surface during the afternoon and early evening leading to windy conditions. The plains and valleys can expect sustained winds of 15-20 mph gusting to 20-30 mph. Additionally, downslope flow will lead to hot temperatures and very low relative humidity values in the mountain valleys and eastern plains. Given the recent wet period across the eastern plains and valleys, the threat for rapid wildfire spread will remain low despite Red Flag weather conditions (strong winds and low RH). High temperatures across the plains will run around 15 degrees fahrenheit above average, pushing 100 degrees along and east of the I-25 corridor. Sunday and Monday...not much change to the upper pattern with an upper low slowly drifting into the Northern Rockies. This will keep dry southwesterly flow across Colorado allowing for strong afternoon mixing. Gusty winds will continue at the surface and temperatures are forecast to remain in the 90s to lower 100s. In addition, fire weather conditions may become more critical as we move into Monday. Several days of hot, dry conditions may allow for fine fuels to become more susceptible to fire ignition. We will continue to monitor fuels with land management agencies through the weekend into early next week. No precipitation is anticipated through Monday. Tuesday through Thursday...the upper level low will continue east across the Northern Plains into the Great Lakes. A cold front will drop south across the region by Tuesday with slightly cooler air. This will keep highs generally in the 80s to mid 90s for the lower elevations. Flow aloft will remain westerly and dry, keeping precipitation chances nil across southern Colorado. Fire weather conditions will likely remain elevated, however, winds are likely to be marginal. Line/Mozley && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 249 PM MDT Thu Jun 8 2017 KALS could see showers/tstms in the vicinity through about 02Z, and gusty outflow winds could affect the site. Otherwise KALS should have VFR conditions through Fri, with southwest winds picking up in the afternoon hours with gusts of 20-25 kts. KPUB and KCOS are expected to have VFR conditions for the next 24 hrs. There is a small chance for showers or tstms to move into the vicinity of KPUB and KCOS early this evening, with gusty erratic winds being a threat. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...LINE/MOZLEY AVIATION...28
Area Forecast Discussion
National Weather Service San Angelo TX
630 PM CDT Thu Jun 8 2017 .AVIATION... /00Z TAFS/ VFR conditions will persist through the evening and into Friday afternoon for the KSJT, KSOA and KBBD terminals. Isolated showers and thunderstorms are possible by 10Z, impacting the KABI terminal. Brief MVFR conditions are possible with these showers and thunderstorms. Development of afternoon thunderstorms could impact the southern terminals by 18Z. && .PREV DISCUSSION... /issued 347 PM CDT Thu Jun 8 2017/ SHORT TERM... (Tonight and Friday) All models show some type of convective complex developing late this afternoon and early this evening across the South Plains, and then moving southeast into West Central Texas after midnight. The models differ however, on the track of the system and thus where the rain end up. The GFS is farther east, moving across portions of the northern and eastern Big Country and into North Central Texas. The latest WRF from Texas Tech show a complex farther west, with the brunt of it dropping south across the western Big Country into the Concho Valley by morning. The HRRR has something in the middle, with a broader complex of storms that covers a wider area. At this point, will increase PoP`s slightly for tonight and tomorrow morning over an area mainly north of a San Angelo to Brownwood line. Given the chance that this system will be strong enough to leave some sort of outflow boundary across the area, will include a mention of isolated storms for tomorrow afternoon all the way south to Interstate 10 as well. Temperatures will not be changing very much, so lows in the upper 60s and lower 70s, with highs in the mid and upper 90s look good. LONG TERM... (Friday Night through next Thursday) For this weekend, a weak closed low is forecast to develop near the Texas/Louisiana border and then drift south- southwest to just east of Brownsville by Sunday. Weak upper ridging will be in place to the north of this low over the southern Plains. This pattern is expected to result in minimal rain chances for our area during the weekend. While little change is expected with our high temperatures, expect an uptick in overnight lows as dewpoints increase with south-southeast low-level flow. Breezy conditions are expected with lee surface trough to our west and increased pressure gradient across our area. Early next week, an upper low over the western CONUS will lift northeast across the northern Rockies by Tuesday, and into the northern Plains late Tuesday night into Wednesday. An upper level high will be centered over Mexico, with an extension into southwestern Texas. This will be our dominant weather feature through the first half of the week. Afternon highs are forecast to be in the lower to mid 90s, with overnight lows mostly in the lower 70s. By late week, quasi-zonal flow aloft is progged to the north of the aforementioned high, with the possibility of a couple of embedded disturbances moving east across the southern Rockies into the southern Plains. This may increase rain chances for the northern part of our area by Thursday. && .PRELIMINARY POINT TEMPS/POPS... Abilene 71 93 71 94 / 30 20 5 5 San Angelo 71 94 70 96 / 10 20 5 5 Junction 69 90 69 92 / 10 20 5 0 Brownwood 70 90 68 92 / 20 20 5 5 Sweetwater 70 95 70 95 / 30 20 5 5 Ozona 69 95 70 94 / 5 20 5 0 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ 99/99/40