Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/16/17


Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
554 PM MDT Sat Jul 15 2017 .AVIATION... 00Z TAF CYCLE Ely wave ovr west TX will set the stage for an active evening across central and northern NM. Thunderstorm outflows from the north will collide with outflows from the south to generate evening thunderstorms at most terminals through 16/06Z. Storm motion will be slow and highly variable. Brief MVFR cigs/vsbys with combined wind and rain/small hail will result from the stronger storms. Convection will favor northern and western areas of the state Sunday afternoon and evening. 33 && .PREV DISCUSSION...244 PM MDT Sat Jul 15 2017... .SYNOPSIS... Daily rounds of showers and thunderstorms remain on tap for the next several days. Storm coverage should increase on Sunday and Monday compared to today, especially over northern and western New Mexico. Storm motion will remain quite slow, which will increase the potential for heavy rains. A more robust monsoon plume should develop over Arizona and far western New Mexico by mid week. Thanks to the cloud cover and precipitation, high temperatures should be near to just below average for the next week. && .DISCUSSION... Showers and thunderstorms started early today over the high terrain, but have not gained much ground since then. An area of dry air/subsidence is in place over central and east central NM in associated with the easterly wave. This will keep showers and thunderstorms largely at bay for the rest of the afternoon in these areas. However, the HRRR has been consistently suggesting that thunderstorms now developing in southeast CO will become more organized as drop into NE NM this evening as they move around a weak mid level low. Once these storms encounter the drier air and subsidence associated with the easterly wave, they will likely dissipate. Sunday should be more active, though much of the east central and southeast plains will be left out. Storm motion will continue to be slow, which may result in locally heavy rains. On Monday, the upper high that is currently centered over southern NV will elongate eastward from NV to OK. Potentially multiple high centers will again make storm motion slow and variable. By Tuesday, the main high center will develop over Oklahoma. The question will be how far westward will the high be elongated and how strong will it be. Seems like the GFS and ECMWF are slowly coming toward a single solution which is that the high will probably be strong enough to steer the best monsoonal moisture into AZ and far western NM on Tuesday, and likely on Wednesday as well. Started to trend down PoPs across the central NM mountains both days, but if the trend continues, PoPs will need to be adjusted down further. There`s potential by the end of the week that the high will weaken enough for storm coverage to begin increasing again. By early the following week, both the GFS and ECMWF are showing the moisture plume square over NM. Stay tuned. 34 && .FIRE WEATHER... Active weather through next weekend. Still questions though as to where the best plume of moisture sets up next week, but it`s looking like western NM could take top honors. Showers and thunderstorms have developed earlier today, both over the mountains and even in parts of the eastern plains. Should be an active evening with some storms lasting past midnight. The slow movement of the storms could result in minor flooding of roads and low lying areas. The easterly wave to the south and low pressure center in CO will head in opposite directions, both of them slowly moving away from NM tonight and Sunday. But the high pressure anchored near Las Vegas, NV will weaken some and PW values will come up a little, allowing for another good round of showers and thunderstorms Sunday. The slow moving storms could generate heavy rain producing localized flash flooding. The Las Vegas high pressure area will weaken a little more early next week while the high over the central plains builds. This will set up a favorable southeast to northwest flow of moisture from the Gulf of Mexico, across TX and into Mexico before reaching us. The primary plume looks like it will set up across western NM, with the ECMWF grudgingly giving up on the farther east plume of moisture. A couple of inverted troughs/easterly waves could add to the mix later next week and next weekend. This all adds up to widespread convection next week into the weekend, primarily across the western half of the state. Moderate or lower Haines values are forecast through next week. Generally fair or better vent rates, except for patches of poor rates over western and northern areas. Nighttime RH recoveries will be good to excellent. CHJ && .ABQ WATCHES/WARNINGS/ADVISORIES... None. && $$ 34
Area Forecast Discussion
National Weather Service La Crosse WI
634 PM CDT Sat Jul 15 2017 .SHORT TERM...(This evening through Sunday) Issued at 257 PM CDT Sat Jul 15 2017 At 245 PM, a cold front extended from Marquette Michigan to Sioux Falls South Dakota. The visible satellite loop shows that much of the clouds are located in the wake of this front. With plenty of sunshine ahead of this front, temperatures have warmed into the 80s and they will likely warm into the 85 to 92F range by late afternoon. Southwest winds have advected dew points to around 70F. Looking further downstream, there will a strong possibility that they will climb into the mid 70s in some locations. This will result in surface based CAPES of 3000 to 4500 J/kg by late afternoon and early evening. Looking at the RAP soundings, still some questions on how far west the convection will develop. At this time, feel good that the counties along the Mississippi River and east will see scattered storms develop. Further to the west, the cap may hold. Soundings continue to show that shear is less 30 knots or less, so the shear looks rather marginal for supercells. However, the soundings and DCAPE (1000 to 1700 J/KG) are very favorable for microbursts. In addition, the NCAPE is favorable for large hail (maybe up limes or 2 inch in diameter). With limited low level shear not seeing much for tornadic development. However, we will have to watch out for the storms potentially interacting with outflow boundaries from previous storms. The highest threat for storms and severe weather will be from 4 PM to 10 PM. For late tonight and Sunday morning, the models continue to show some 925 and 850 mb moisture across the region. Since the current satellite is showing this moisture in the wake of the cold front and this has been a consistent feature, increased the cloud percentages some. .LONG TERM...(Sunday night through Saturday) Issued at 257 PM CDT Sat Jul 15 2017 The models continue to show that a short wave trough will flatten out the 500 mb ridge from Monday night through Tuesday. As this occurs, a frontal boundary will move into the Upper Mississippi Valley. This boundary than lingers across the area through Thursday. As short waves embedded in the westerlies move through the area, there will likely be several rounds of storms from Monday night into Thursday. Still plenty of questions on where these mesoscale convective complexes will end up and when they will move through the region. At this time, there is some consensus that one may move through areas north of Interstate 94 on Monday night and Tuesday morning, another one on Tuesday afternoon and night, and then a final one Thursday as a cold front moves through the region. There will be the potential for severe weather and heavy rain, but with questions on the southern extent confidence was not high enough to include this in the forecast at this time. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 634 PM CDT Sat Jul 15 2017 Watching a narrow line of scattered thunderstorms dropping southward across the area this evening. Current radar trends suggest storms should remain just east of KRST, but impact KLSE between 15.01Z and 15.03Z. Given some lingering coverage uncertainty, will just keep VCTS at KLSE, but may need to add a TEMPO or predominant thunder with lower ceilings/visibility in the next couple hours. Storms are forming along a weak cold front and once it passes south of TAF airfields, expect a return to VFR conditions with winds shifting to the northwest. Still watching the potential for some MVFR stratus Sunday morning at both KRST/KLSE, but should be short lived. Otherwise, expect periodic VFR cumulus with light winds shifting to the northeast. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...Boyne LONG TERM...Boyne AVIATION...Rogers
Area Forecast Discussion...UPDATED
National Weather Service Duluth MN
850 PM CDT Sat Jul 15 2017 .UPDATE... Issued at 850 PM CDT Sat Jul 15 2017 Cold front has moved well south into central Wisconsin as of mid evening, with cooler and drier air filtering into the Duluth CWA as high pressure builds in from the north. Overall, we expect a fairly quiet weather night. However, GOES-16 imagery and surface obs indicate a fairly well- organized secondary northeasterly surge moving southwest-ward near Isle Royale and the Minnesota Arrowhead, with a well-defined wind shift/cloud line, and Rock of Ages is now gusting to 25 knots from the northeast. The previous forecast and hi-res guidance hinted at this feature earlier, and it appears that guidance was on to something. Confidence in any meaningful precip with this as it reaches the south shore later tonight is very low, but it should be sufficient for a period of locally stronger winds, cooler temps, stratus clouds and perhaps some drizzle in the primary upslope areas prone to northeast flow. We have updated the forecast to reflect these trends, and also increase the coverage of patchy fog in many areas during the overnight hours. && .SHORT TERM...(This evening through Sunday) Issued at 330 PM CDT Sat Jul 15 2017 At 330 PM, skies were partly to mostly sunny across the Northland. Temperatures ranged from 86 at McGregor, to 73 in Crane Lake, where there was a bit more extensive cloud cover. Winds had generally shifted to the north/northwest across the entire CWA. The focus for tonight will be the potential for a few showers and thunderstorms, along with the potential for some late night stratus/rain showers off Lake Superior. Quite unstable air across northwest Wisconsin this afternoon. CIN has been decreasing across that area, although there was still a bit of a cap on forecast soundings across that area. These forecast soundings indicate there will exist a small window where storms could develop late this afternoon or early evening, although the threat will quickly shift south of the CWA with time. The CU field elsewhere across the CWA has not shown much growth at all, but would not be surprised to see a few showers or a storm across the Minnesota Arrowhead this afternoon. Still, the best chance for some development would be south of a line from Hayward to Ironwood. Dewpoints in this area are in the lower 70s as of 3 PM. The rest of the Northland should see skies generally clear overnight. The HRRR is consistent in trying to bring some stratus and perhaps some spotty rain showers or drizzle to the areas surrounding Lake Superior overnight, first along the south shore, and then across the Twin Ports and portions of the North Shore. Any clouds/showers that do develop overnight should gradually break up on Sunday, as high pressure brings sunshine to the CWA. Lows tonight will range from the 40s in the north to the 50s to around 60 south. Highs on Sunday will range from the 60s to lower 70s near Lake Superior, to the 70s inland. .LONG TERM...(Sunday night through Saturday) Issued at 330 PM CDT Sat Jul 15 2017 A ridge of high pressure will build southeastward into the central Great Lakes Sunday night, while a trough lifts into the central Canada. At the surface, high pressure will slide from the Upper Midwest into the central Great Lakes. Behind the surface high, a cold front will move into the northern Plains and northwest Minnesota. On Monday the front will slide southeastward through much of northern Minnesota. This will bring increasing chances of showers and thunderstorms late Sunday night through Monday. It will be humid with mid 60s to near 70 degree dewpoints advecting into the region ahead of the front due to southerly flow. In addition, there will be 1500-3000 J/kg of MLCAPE, 0-6 km bulk shear increasing to 25 to 40 kts, and PWATS of 1.5 to 2.0 inches per the GFS/NAM/ECWMF. Based on these parameters combined with forcing from the front, strong to severe storms will be possible as highlighted in the current SPC Day 3 Outlook. With PWAT values near the 90th percentile for this time of year, heavy rainfall will also be a concern. Highs on Monday will range from the mid 70s along the Lake Superior shoreline, to the upper 80s in the Brainerd Lakes region. The cold front will slowly continue sliding southeastward through the Northland Monday night and Tuesday. Aloft, another shortwave will be moving through bringing continued shower and thunderstorm chances. Cannot completely rule out strong to severe storms on Tuesday especially if the latest GFS pans out with MLCAPE of 1500- 2500 J/kg with 0-6 km bulk shear of 40-50 kts. Think these instability values may be a bit overdone as cloud cover from the ongoing/previous days convection should inhibit the amount of daytime heating. By Wednesday, the GFS stalls the cold front across southern portions of the CWA, while the ECMWF/CMC are more progressive and have already moved the front through. Uncertain at this point how things will evolve, but opted in continuing shower/storm chances as another shortwave will be moving through. High pressure will build into the region Thursday/Friday as an 850 hPa ridge axis moves northeastward from the northern Plains into the Upper Midwest. Late in the week and heading into the weekend, a trough will move into the Upper Midwest from central Canada bringing more chances of showers and storms. Expect seasonable highs for Tuesday through Saturday with readings in the 70s and low 80s. Lows range from the 50s to low 60s Tuesday night through Friday night. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 647 PM CDT Sat Jul 15 2017 Cold front has cleared all of the TAF sites as of 00z, with north/northwest winds and diminishing fair weather cumulus field. VFR conditions are expected throughout the period, with the only risk for some MVFR conditions being near the south/southwest shore of Lake Superior later tonight/Sunday morning as winds become northeast. Scattered to broken cumulus should develop in most areas again Sunday, but any ceilings are expected to be well above MVFR thresholds. && .PRELIMINARY POINT TEMPS/POPS... DLH 57 69 48 78 / 10 10 0 20 INL 48 77 54 79 / 0 0 10 50 BRD 57 77 58 87 / 0 0 0 20 HYR 53 74 50 82 / 10 0 0 10 ASX 55 69 48 82 / 10 0 0 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ UPDATE...Miller
Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
953 PM CDT Sat Jul 15 2017 .UPDATE... The diurnal activity across North and Central Texas has come to an end, but showers and thunderstorms remain upstream. Some of these cells may slip into northern portions of the CWA into the early morning hours. The complex in western Oklahoma will likely dissipate as the impulse responsible for its initiation outruns it. However, this disturbance may result in renewed development across North and Central Texas early Sunday morning. The coverage should be isolated at best with lightning the primary concern. 25 && .AVIATION... /Issued 734 PM CDT Sat Jul 15 2017/ Showers and thunderstorms that were scattered across North Texas this afternoon had dissipated as of 00Z. The remainder of the night should be quiet with VFR and scattered to broken high clouds. We are watching the convection currently across western Oklahoma. This activity should weaken as it approaches the Metroplex TAF sites overnight as per HRRR and TTU WRF solutions. There will be an outside chance of a shower across the Metroplex TAF sites toward sunrise Sunday, but impacts should be minimal. Sunday will be VFR with scattered daytime CU and a few afternoon showers and isolated storms in the late afternoon. An east to southeast will prevail at speeds generally less than 10 knots. 79 && .DISCUSSION... /Issued 345 PM CDT Sat Jul 15 2017/ Showers and thunderstorms have been most numerous this afternoon across Central Texas and the southeastern part of North Texas. This is the area that was south of this morning`s outflow boundary. A few strong storms have produced wind gusts in excess of 40 mph. Rainfall rates are high as you would expect with nearly 2 inch Precipitable Water Values. Fortunately the storms are moving at around 15 mph but some training may still result in localized flooding issues. Other thunderstorms occurred west of a Hillsboro to Jacksboro line in the untapped air there and also across areas east of a Sherman to Athens line where the remnants of some of this morning`s activity refused to die. There was quite a variation in temperatures with mid to upper 80s across areas north and northeast of the Metroplex and mid to upper 90s across parts of Central Texas before the storms hit. A weak shortwave will continue to move around the eastern periphery the upper level high centered to our northwest but with the loss of daytime heating, expect most of the showers and thunderstorms to decrease in areal coverage toward sunset. Cannot completely rule out additional showers and thunderstorms overnight, so have left some 20 percent PoPs for the late evening through the overnight hours area wide. Lows will be in the 70s. With the upper ridge remaining to our northwest on Sunday, we will keep at least a slight chance of showers and thunderstorms with the best chances (30 percent PoPs) being southeast of a Goldthwaite to Waxahachie to Paris line. Highs will be in the 90s area wide with heat index values reaching 98 to 107 degrees. The ridge will build eastward across Kansas and Oklahoma during the early part of the week and the strengthen its grip on North and Central Texas during the middle to late part of next week. This will result hot weather with chances of showers and thunderstorms shifting southward. We will be near heat advisory criteria especially along and east of the I-35 corridor. 58 && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 77 96 77 97 77 / 20 20 10 20 10 Waco 74 97 75 96 75 / 20 30 20 30 20 Paris 75 94 73 93 73 / 20 20 10 10 10 Denton 75 95 74 95 75 / 20 20 10 10 10 McKinney 74 95 74 95 75 / 20 20 10 10 10 Dallas 78 97 78 97 77 / 20 20 10 20 10 Terrell 75 95 74 95 75 / 20 30 10 20 10 Corsicana 75 96 74 95 74 / 20 30 20 30 20 Temple 73 96 74 96 74 / 20 40 20 30 30 Mineral Wells 75 95 73 96 73 / 20 20 10 10 10 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 25/79
Area Forecast Discussion
National Weather Service Goodland KS
826 PM MDT Sat Jul 15 2017 .UPDATE... Issued at 821 PM MDT Sat Jul 15 2017 Storm intensity has transitioned to light to moderate rain. Latest data indicates the best chance for rainfall tonight will be over mainly Cheyenne County CO and western parts of Wallace and Greeley counties. For this part of the forecast area lift from the closed low overhead will persist through the night, which should result in continued rain activity. Early in the morning lift will reach a minimum then increase as temperatures warm. && .SHORT TERM...(This afternoon through Sunday) Issued at 202 PM MDT Sat Jul 15 2017 Mid level upper low continues to linger over eastern Colorado, with deep plume of moisture overriding our CWA. Thunderstorm coverage has continued to increase early this afternoon, and there has been one report of severe hail near the NE state line with one of the stronger cells. High resolution guidance continues to favor increasing coverage through the rest of the afternoon then decreasing coverage near sunset. With a tendency for slow moving clusters along narrow regions of mid level vorticity it is hard to zero in on overall coverage, so I have continued to hedge towards high "chance". I could see increasing coverage for some locations, but I will wait in until we have a better handle on short range trends. With mid level circulation and moist plume lingering I would expect at least a few showers or weaker thunderstorms overnight tonight and Sunday morning. Coverage should increase midday Sunday, with increase in lapse rates due to daytime heating and models support this trend. Regarding severe potential: Meso analysis from RAP indicates axis of 2500-3000 J/KG ML CAPE is in place over the northeast 2/3 of our CWA, with very weak shear and slow 0-6km winds. PWATs are shown to be anomalously high with values in excess of 1.5" across our KS counties. Considering antecedent conditions isolated severe hail and localized flash flooding would be the main concerns. RAP/NAM show downward trend in CAPE, and a decreased severe threat after sunset. We could see a repeat Sunday afternoon, with similar conditions over at least part of our CWA. .LONG TERM...(Sunday night through Saturday) Issued at 202 PM MDT Sat Jul 15 2017 Sunday night-Tuesday: Weak closed upper level low meanders across the area through Monday morning. This, combined with surface troughing and abundant 700mb moisture, will bring chances of rain and thunderstorms to southeastern portions of the CWA. Will carry slight chances of storms on Monday and Tuesday afternoons due to residual moisture and troughing. Temperatures will warm through the period. Wednesday-Thursday: Upper level ridging dominates the weather through the period. Today`s 12Z runs of the GFS and ECMWF are in better agreement on temps than yesterday`s. Temperatures will be well above normal with some areas at or above 100 degrees for highs both days. Friday-Saturday: Models are not in good agreement for this period, so have low confidence in this portion of the forecast. Ridge progresses off to the east, putting the area in more of a zonal flow pattern aloft. Could see some showers/storms by Saturday. Temperatures appear to remain above normal. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 517 PM MDT Sat Jul 15 2017 VFR conditions expected for the TAFs. Main impact will be the rain activity at KGLD in the first couple hours of the TAF. Latest radar shows an area of rain just south of the site. If the rain moves overhead, will end in a few hours. Last 20 minutes of radar data show the rain moving very little to the north, which gives concern that it may not move over KGLD. KMCK will remain north of the storm activity. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JTL SHORT TERM...DR LONG TERM...SME AVIATION...JTL
Area Forecast Discussion
National Weather Service Green Bay WI
1045 PM CDT Sat Jul 15 2017 Updated aviation portion for 06Z TAF issuance .SYNOPSIS... Issued at 229 PM CDT Sat Jul 15 2017 Scattered thunderstorms through this evening, then a couple days of quiet weather. Humid conditions and more thunderstorms will return mid-week. A band of westerlies was located across northeast Canada, flowing around a deep upper low over northern Hudson Bay. Farther south, another fairly amplified band of westerlies stretched across southern Canada and the northern CONUS. Within that branch of the flow, there were troughs along the West Coast and over New England, with a ridge over the Intermountain West. That branch of the flow will amplify a bit more during the next 24 hours and then begin to deamplify as the main features within it become progressive. There will also be some consolidation of the flow across NOAM, with much of Canada becoming dominated by flow around the Hudson Bay upper low. Meanwhile, a lower amplitude flow is forecast to persists across the CONUS from mid-week into the upcoming weekend and beyond. The medium range models have tried that before in the past few weeks, only to have the western ridge/eastern trough pattern reappear. We`ll see what happens this time. Air masses moving across the region favor temperatures falling off to a little below normal the next couple days, then warming back to near or above normal for the rest of the forecast period. But temperatures are likely to be held back on days with widespread clouds and convection. At least a couple more humid days are likely mid-week. The area will spend enough time near the main frontal zone lingering near the southern edge of the westerlies to result in above normal precipitation amounts for the period. Totals could end up being quite heavy, depending on the movement of individual convective systems. && .SHORT TERM...Tonight and Sunday Issued at 229 PM CDT Sat Jul 15 2017 The latest RAP analysis and satellite/radar imagery show a cold front stretching from just northwest of Minneapolis to northwest WI early this afternoon. 12z soundings from GRB and MSP indicate a rather stout cap in place across the region, beneath an elevated mixed layer comprised of some very dry air. Will probably take until after 21z for convection to break through the cap, which the mesomodels support as well. Once developed, ml capes upwards of 2000 j/kg and 0-6km bulk shear of 30-35 kts will be supportive of severe thunderstorms capable of producing damaging straight line winds and large hail. The storms should then proceed southeast from north-central WI late this afternoon, into central and northeast WI by early this evening. Besides severe weather potential, forecast also centers on gusty north winds. Tonight...The cold front will continue to move southeast across central and northeast WI during the evening before exiting around midnight. Instability and shear will remain supportive for severe thunderstorms until the front exits, including damaging winds and large hail. Behind the front, north winds will ramp up and will likely become gusty along the Bay and Lake. Scattered to broken cloud cover from north of Lake Superior is expected to reach into northern WI late tonight, though not sure how far south these clouds will make it. Did increase sky cover some though. After a warm and stormy evening, temps to fall into the mid 50s north to mid 60s south. Sunday...High pressure will build in from the north, with winds turning to the northeast. With gusts of 20-25 kts and waves approaching 4ft, will issue a small craft advisory, starting late Saturday night. Should have some scattered to broken clouds through late morning/midday before dry air mixes out the clouds. Temps will be cooler, with highs ranging from the low to mid 70s. .LONG TERM...Sunday Night Through Saturday Issued at 229 PM CDT Sat Jul 15 2017 High pressure across the area will create light winds and mostly clear skies, so temperatures should drop off considerably Sunday night. Patchy fog could also develop, but that will depend partly on the coverage and rainfall amounts from today`s late afternoon/evening storms. Not surprisingly given the flattening of the upper flow, models started to offer differing ideas on how quickly convection in the return flow around the high would move into the area. Stayed with the broad-based blend of guidance for PoPs, and that resulted in mainly chance PoPs Tuesday through Thursday. Would like to say we`ll be able to add significant detail to those in coming days, but this may wind up being another one of those situations where it`s tough to gauge convective evolution more than 12 hours in advance. The overall pattern looks favorable for heavy/excessive rainfall somewhere near or in the forecast area. Will reflect this with more aggressive wording in the HWO. A severe risk could also evolve at some point as well. Even the relatively flat flow on the medium range guidance tilts northwest just enough to drive the main frontal zone south of the area by late in the week, though they also show the return flow developing pretty quickly. There will probably be a dry day in there somewhere--most likely Friday. && .AVIATION...for 06Z TAF Issuance Issued at 1045 PM CDT Sat Jul 15 2017 Showers and thunderstorms have ended behind a departing cold front. In its wake mostly clear skies and VFR conditions are expected through Sunday. Although the amount of rain the area received this evening would suggest patchy fog, MOS guidance does not generate fog as it keeps winds up with falling dew points. Therefore will continue to leave fog out of the TAFs with this issuance but would not be surprised to see some form given the rainfall. && .GRB WATCHES/WARNINGS/ADVISORIES... Beach Hazards Statement from 7 AM CDT Sunday through Sunday evening for WIZ050. && $$ SYNOPSIS.......Skowronski SHORT TERM.....MPC LONG TERM......Skowronski AVIATION.......Kurimski
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1044 PM EDT Sat Jul 15 2017 .SYNOPSIS... Hot and humid conditions will persist through the weekend, with scattered to numerous afternoon and evening thunderstorms each day. A cold front will move into the region from the northwest and stall near the area through Sunday. Another cold front will approach on Monday and move southeast of the area on Tuesday, with drier and warmer conditions arriving by the middle of next week. && .NEAR TERM /THROUGH SUNDAY/... As of 1030 PM EDT: Another quick update mainly to PoPs and Temps to reflect latest trends. Am seeing a few showers popping up across the southern Upper Savannah Valley. There is not much CAPE left to work with, but will bump up PoP for the next couple hours there. Elsewhere, the CAMs still hint at spotty redevelopment overnight. The last few runs of the HRRR have been consistent in showers developing over the NW NC piedmont after midnight. Not sure what it is keying on. But the front is in the area, and there is still 500-1000 J/kg of MUCAPE with low LFC heights. So I will keep a slight CHC PoP in for most of the area thru the overnight. Not expecting too much additional convection. Otherwise, expect a mix of mid and high clouds with temps near to slightly above normal. Convection pick up at least across southern zones on Sunday. Some of the hires models want to develop some showery activity across the northern tier as well so have kept pops a little higher, but these may need to be pulled back down with later forecasts. Temperatures will be improving through the period, with highs today near seasonal normals, lows tonight just slightly above and highs tomorrow actually a couple of degrees below. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... As of 130 PM EDT Saturday: A shortwave embedded in upper longwave troughing will cross the area Sunday night as a surface front settles over the forecast area. The front will wash out on Monday as heights aloft fall and another potent shortwave rounds the trough base, so widespread showers and thunderstorms are anticipated once again on Monday. Another front will descend from the northwest on Monday night and will stall near the forecast area Tuesday, providing a focus for enhanced diurnal convection in the afternoon. Mid-level dry air makes an entrance Monday and Tuesday, and with respectable instability both days, some type of wet microburst threat is possible. Temperatures will be near climo. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... As of 100 PM EDT Saturday: The medium range begins Tuesday night immediately post-frontal passage with a few lingering showers and thunderstorms. Upper troughing lifts by Wednesday, though there is some model disagreement in just how far the front is able to progress as it washes out on Wednesday. Strong upper ridging builds over the central Plains on Wednesday to exert some influence on the southeast, though, so maximum temperatures were increased and "silent 10" pops remain. The extent to which drier air will be able to work in as the ridge continues to build Thursday and Friday is also uncertain, but enough moisture lingers in the global model solutions that slight chance pops were maintained both afternoons. A back door front dips down from the northeast as upper heights fall again on Saturday, bringing pops close to climo back into the forecast. Maximum and minimum temperatures during the middle and end of next week will be above climo through the period, though the extent is uncertain due to model inconsistencies in handling the sprawling high over the central Plains. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... At KCLT and Elsewhere: Convection got an early start and is now south and east of the area as of 00z TAF issuance. Some debris cloudiness and a few spotty light showers may linger thru the evening, but overall VFR conditions are expected heading into the overnight. But after around midnight, expect valley fog and stratus to develop in the mountain valleys. With a front stalled over the piedmont, guidance shows more mid-level moisture and not hitting fog or stratus too hard. However, if skies manage to clear and winds remain light, could see some areas of fog and/or stratus over portions of the piedmont. For now, will only put in some MVFR vsby late tonight at KAND/KGSP/KHKY. For Sunday, the front will remain close to the Piedmont sites, and guidance is in good agreement on enough instability for mountain-top convection as well. So will put PROB30 groups in all TAF sites for Sunday afternoon. Winds will be light, favoring a N/NW direction tonight, then switching back to S/SW by early afternoon. Outlook: Scattered to numerous afternoon and evening thunderstorms are expected both Monday and Tuesday across the area, with higher coverage in the mountains. Morning fog development can be expected in the mountain valleys and in areas that receive rainfall the previous afternoon/evening. Drier air will limit convective coverage to more isolated for Wednesday into late week. Confidence Table... 02-08Z 08-14Z 14-20Z 20-00Z KCLT High 100% High 98% High 100% High 100% KGSP High 100% High 100% High 100% High 100% KAVL High 95% Med 73% High 97% High 100% KHKY High 100% High 95% High 100% High 100% KGMU High 100% High 100% High 100% High 100% KAND High 100% High 100% High 90% High 100% The percentage reflects the number of guidance members agreeing with the scheduled TAF issuance flight rule category. Complete hourly experimental aviation forecast consistency tables and ensemble forecasts are available at the following link: www.weather.gov/gsp/aviation && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...Carroll NEAR TERM...ARK/TDP SHORT TERM...Carroll LONG TERM...Carroll AVIATION...ARK
Area Forecast Discussion
National Weather Service Huntsville AL
626 PM CDT Sat Jul 15 2017 .UPDATE... For 00Z TAFS. && .NEAR TERM...(Tonight) Issued at 626 PM CDT Sat Jul 15 2017 Went ahead and made some updates to the forecast for the rest of the evening, mostly to account for diminishing radar trends and quick cooling of the locations that have received heavy rainfall. At 21z, WPC analyzed a stationary front sitting west to east across our middle TN counties and it is very difficult to identify where that boundary is now or if it`s even there. Winds are light and variable and dew points aren`t falling much to the north and the only tip would be a theta-E boundary that`s been moving through the area and is now to the south. Current LAPS soundings show cooling at the surface thanks to the rain and outflow boundaries and has quickly weakened the ongoing storms with little to no lightning ongoing across the area. The storms that were impacting the area earlier have diminished into light to moderate rainfall and mainly impacting areas around Huntsville and farther south. Looking at the latest HRRR runs as well as the deep dry air moving in from the north, evident on the multiple GOES-16 water vapor bands, it looks like we should stay mostly dry overnight after this batch weakens and moves off to the south. However, given the questionable boundary that will linger and PW values staying around 1.5 inches overnight, will keep the mention of isolated storms. Granted, I am not overly confident we`ll get any rumbles overnight, probably just isolated showers. The one major change to the forecast was the addition of fog overnight. Dew points won`t drop very fast overnight and we could see some clearing skies by midnight. The areas that received rainfall will likely see patchy fog at least and will monitor to see if we need to increase the coverage. .SHORT TERM...(Sunday through Monday) Issued at 309 PM CDT Sat Jul 15 2017 Sunday will be more typical of mid-July with scattered showers and storms, perhaps favoring the southeast part of the area where better moisture will linger. However, while the threat of heavy rain abates, the increasing mid-level dry air and steep lapse rates could increase the threat for strong microbursts. Monday will bring another weak shortwave into the area, but it will do more to bring deeper dry air into the area than increase precipitation coverage. All in all, PoPs for the next two days will be much more typical for mid-July than they are today: generally in the 20-30% range and with slightly higher values to the southeast where more persistent moisture exists. High temperatures will decrease slightly, back to seasonal norms for July, while low temperatures will stay more or less persistence. .LONG TERM...(Monday night through Friday) Issued at 309 PM CDT Sat Jul 15 2017 A shortwave will dive from the Great Lakes down into the Appalachians on Tuesday as a ridge anchored over the central U.S begins to expand into the Southeast. At the sfc, a weak front will be south of the area with high pressure building in from the north. A few showers and thunderstorms are possible across the TN Valley Tuesday afternoon with highs in the upper 80s to lower 90s. Some drier air filters into the region Tuesday/Wed, but a few showers/storms are still possible Wed afternoon with temps in the upper 80s/lower 90s and heat index values reaching the mid/upper 90s. The building ridge will increase temps through the week reaching the low/mid 90s by Friday. With southerly flow, moisture returns towards the end of the week. This will increase the heat index values, reaching 100 degrees or slightly above by Friday. Look for isolated to scattered showers/storms Thurs and Friday afternoon as the shortwave cuts off then retrogrades westward. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 626 PM CDT Sat Jul 15 2017 Showers/storms are almost over for the terminals and will keep both terminals dry for the TAFs. An isolated shower or storm is possible overnight but confidence is not high enough to include in the TAFS. CIGS may rise slightly in the next few hours but lower clouds may move in by morning. In addition, fog is possible and have added a TEMPO group for 3SM and BKN020. CIGS should rise after sunrise with sct/bkn afternoon clouds expected on Sunday. Winds will remain light and variable through the TAF period. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ NEAR TERM...LN/BCC SHORT TERM...BCC LONG TERM...JMS AVIATION...LN For more information please visit our website at weather.gov/huntsville.
Area Forecast Discussion
National Weather Service Lubbock TX
633 PM CDT Sat Jul 15 2017 .AVIATION... VFR and light winds. Very isolated showers and occasional TS will dwindle after sunset, before returning Sun afternoon with a bit more coverage near an easterly wind shift. This boundary will push through CDS in a few hours, but slow or stall as it reaches LBB and PVW on Sunday. Later TAFs may entertain TS mention on Sun if prospects for TS improve. && .PREV DISCUSSION... /issued 252 PM CDT Sat Jul 15 2017/ DISCUSSION... Isolated convection has started to develop across the northwestern Permian Basin/southeastern NM and the southern South Plains along the edge of the caprock. The main sources of lift are weak surface boundaries. The RAP and the HRRR have been the only models hinting at these isolated showers/thunderstorms. These reason seems to be that they appear to be handling the mid and upper level dry air better than the larger scale models. WV shows a pocket of dry air across the central TX Panhandle into western OK. Models such as the GFS and NAM have this dry air pushing south and westward over the FA by this afternoon. WV actually shows this area of dry air to be shrinking as it is being overtaken by moisture associated with a shortwave over northern Mexico as well as gulf moisture. Showers and thunderstorms that develop this afternoon and evening should dissipate by midnight. The one exception may be convection associated with the cold front across our northeastern zones. Another area of possible precip development is across our northeastern zones close to the surface front which is across central OK/northern TX Panhandle. Convection has already begun to develop along the front and is slowly pushing southward. Better rain chances will come tomorrow as deep layer moisture continues to improve. As has been the norm lately, upper level lift, though not nill, will be mostly lacking and any development will be dependent upon surface boundaries left over from convection that happens today as well as the position of the surface front. The NAM forms convection during the afternoon along the front as it pushes westward from the caprock escarpment. The GFS follows suit but holds off until after 00Z tomorrow evening. Pops will only be increased slightly as there is still uncertainty over timing and coverage. Monday still looks to be dry as the upper high takes back its hold on the region. Questions remain on whether the high will continue to block rain chances into mid and late week or if it will weaken and push eastward. The ECMWF and GFS continue to differ on the evolution of the upper high by mid week, but the GFS is slowly changing its portrayal of how the high will evolve next week and, while not fully like the ECMWF, it is more of a match than it has been in recent days. The GFS keeps most of the upper high overhead despite an eastward shift. The ECMWF breaks the ridge down as it brings a few short waves southward from Canada to the southeast helping little by little to erode the ridge. Pops through next week will still remain below mention for most areas as there is still some uncertainty in the forecast, but they will be nudged just a bit higher towards the mentionable mark. && .LUB WATCHES/WARNINGS/ADVISORIES... None. && $$ 93
Area Forecast Discussion
National Weather Service Omaha/Valley NE
612 PM CDT Sat Jul 15 2017 .SHORT TERM...(Tonight through Tuesday) Issued at 305 PM CDT Sat Jul 15 2017 Temperatures will provide the main forecast challenges into Monday then will have to look at precipitation chances for our area. Pattern is still very similar to 24 hours ago, with a large mid and upper tropospheric ridge over the Rockies extending out into the western Plains. Closed low at 500 mb over CO shows up quite nicely in water vapor imagery. Some thunderstorms noted at mid afternoon over parts of eastern CO, western KS and southwest NE. 700 mb temperatures in this area were a little cooler (from KDEN to KLBF) compared to areas farther to the west, north and east. At the surface, synoptic scale cold front was pushing south toward our area. There was another weak boundary that extended from the southwest corner of SD into north central NE. ESRL HRRR keeps most of the activity out over western and parts of central NE into at least early Sunday afternoon, so will keep the forecast dry for now. Look for lows tonight in the upper 60s to around 70. On Sunday, that weak front should start to lift north, but it doesn`t look like convergence will be strong enough to generate any precipitation. Look for highs in the lower and mid 90s. A low pressure system and cold front should move into the western Dakotas Sunday night, with southerly low level in our area increasing a bit. The result will be lows in the upper 60s and lower 70s. Surface pressure gradient and low level winds will be increasing a bit more on Monday, and the closed low that is to our west today should be moving slowly east but as more of an open wave. The front could stay to our south, but the combination of a few different factors may be enough to trigger some showers and thunderstorms in our area, especially by Monday night. The GFS in general seems to have been too aggressive with development of precipitation in our area Monday/Tuesday, but will keep at least some low POPs going. Airmass does not change a lot, so will keep highs Monday (and Tuesday) in the lower and mid 90s. .LONG TERM...(Tuesday night through Saturday) Issued at 305 PM CDT Sat Jul 15 2017 At the start of this period, a 500 mb ridge should stretch from UT and CO eastward into MO and AR. There will be a weak Rex block off the coast of western Canada with the southern branch of polar jetstream from the Pacific northwest across the northern Plains and into Ontario Canada. We will probably be on the northern edge of a hot airmass centered to our south across KS and OK. Some intermittent low thunderstorm chances are expected, mainly Tuesday night and then Thursday night into Friday. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 610 PM CDT Sat Jul 15 2017 VFR conditions are forecast through Sunday evening. Mainly scattered mid and high clouds are expected overnight, then maybe scattered cumulus between FL050 and FL070 Sunday afternoon. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ SHORT TERM...Miller LONG TERM...Miller AVIATION...Dergan
Area Forecast Discussion
National Weather Service Reno NV
155 PM PDT Sat Jul 15 2017 .SYNOPSIS... Isolated thunderstorms remain possible through the weekend. The best chances are each afternoon into early evening over the eastern Sierra into central Nevada, however a couple storms could occur overnight tonight into Reno and Tahoe areas. Low pressure approaching the west coast will increase winds Monday and Tuesday, leading to critical conditions for rapid fire spread. Decreased winds with hot temperatures expected for the balance of next week. && .Short and Long Term Discussion... Rather typical variety of summer weather for next 7-10 days. Here`re the highlights: * Isolated Weekend Storms: Trend for decreased storm coverage today and Sunday remains intact. GOES-16 stability fields really highlight dry and more stable airmass today over W Nevada and much of the Sierra. Exceptions are Mono-Mineral Co, far NE Cal, and Nevada east of Hwy 95 where airmass is more favorable for storm development. Similar scenario for Sunday though guidance is showing even less storm coverage for these areas with more stabilized airmass. * Overnight Storms: Guidance depicting a wave lifting from CA up into Great Basin tonight. Coupled with instability and moisture aloft, HRRR develops a few showers and storms around Reno/Tahoe late this evening into pre-dawn Sunday morning. NCAR 3km ensemble shows something similar but further north. Certainly a concern for fire interests. Predictability of these elevated storm scenarios is typically low - but presence of showers offshore of central California (upstream airmass) does increase my confidence of seeing some cells in our region tonight. * Increased Winds Monday-Tuesday: Low pressure off the Pac NW will drive an increased southwest flow aloft over our region, leading to breezy afternoon-evening winds. 700mb flow nearing 30 kts. While not impactful for travel, this will lead to a critical fire weather scenario. See the fire discussion below for more. * Summer Doldrums Follow: Ridging over the Great Basin resurges mid to late next week, leading to continued hot temperatures but a return to more typical zephyr type winds. Daily thunderstorm potential through next week looks to be mainly confined to central and southern Nevada and the eastern Sierra south of Tioga Pass. * Monsoon Surge Week of 7/23: ECMWF and GEFS ensemble guidance both showing the heat ridge over SW CONUS fracturing some late next weekend into the following week. This could allow a surge of monsoon moisture to work north into the Great Basin, especially if GEFS PW simulations pan out. This could result in a substantial increase in storm coverage in our region starting as early as next weekend. Predictability is marginal but it`s a decent signal this far out. -Chris && .AVIATION... * Typical afternoon and evening westerly winds today and Sunday, so the primarily aviation concern is from isolated storms. Based on recent simulations including HRRR and NCAR 3km ensemble, am not overly impressed with storm coverage each afternoon. Roughly 10- 20%. Most of that would be over eastern Sierra (MMH) into central Nevada (east of NFL). * Potential for some isolated cells overnight tonight near TVL/RNO as shortwave aloft passes by, but predictability of coverage too low at this time to include in TAFs. * Increased west/southwest winds Monday and Tuesday likely to yield more turbulence and some localized wind shear. Gusts on the order of 30 kts possible including RNO each afternoon and evening. -Chris && .FIRE WEATHER... There could be a few stray thunderstorms, about a 5-10% chance, overnight tonight as a weak wave moves through the region. As such, a rare new fire start is possible should any thunderstorms occur. Mid slopes and ridges could see breezy conditions from any passing showers with lighter outflows for valley locations. Otherwise, thunderstorms will be more diurnally driven mainly south of Highway 50 Sunday afternoon. Monday continues to be the focus for critical fire weather conditions. Increasing winds will combine with a significant dry slot resulting in a marked increase in fire concerns; the Fire Weather Watch for extreme northeastern California and western Nevada has been upgraded to a Red Flag Warning. Generally, gusts will be 30-40 mph region-wide and humidity percentages will be in the mid single digits to low teens. Lightning holdovers could start new fires, and these winds will be able to drive fire very rapidly through area grasses and shrubs. Concerns are increasing for Tuesday as model winds continue to increase. Wind gusts are currently expected to be around 30 mph with similarly low humidty as to Monday. A Fire Weather Watch has been issued as a result. Boyd && .REV Watches/Warnings/Advisories... NV...Red Flag Warning from noon to 8 PM PDT Monday NVZ450-453-458-459. Fire Weather Watch from Tuesday afternoon through Tuesday evening NVZ450-453-458-459. CA...Red Flag Warning from noon to 8 PM PDT Monday CAZ270-271-278. Fire Weather Watch from Tuesday afternoon through Tuesday evening CAZ270-271-278. && $$ For more information from the National Weather Service visit... http://weather.gov/reno
Area Forecast Discussion
National Weather Service Blacksburg VA
904 PM EDT Sat Jul 15 2017 .SYNOPSIS... Weak high pressure will build east across the area overnight into Sunday. Showers and storms quickly return to the forecast Monday into Tuesday as disturbances move through the area from northwest to southeast. A more summer like pattern returns to the region by Wednesday into Thursday. && .NEAR TERM /THROUGH SUNDAY/... As of 850 PM EDT Saturday... Surface front has slipped south of the region this evening while the actual dewpoint boundary lingers near the VA/NC border. This seen well via evening soundings with the RNK raob very dry/capped aloft with PWATS half than those seen from GSO where moisture through the column remains deeper. However best support and lingering instability has continued to dip to the south of the region this evening, with a dry pocket along/west of the Blue Ridge per better residual mixing of dry air from aloft this afternoon. Latest short term guidance including the HRRR continues to hint at trying to develop some added showers far south under weak evening convergence and perhaps old outflow but iffy. Therefore may leave in an isolated shower mention over the next few hours before fading to mainly clear skies with some patchy fog around late. Should be a bit more comfortable tonight across central/western sections where dewpoints have dropped enough to allow lows to slide back into the low/mid 60s, with even a few 50s possible deep valleys across the northwest. Will still be muggy over southern sections, with lows closer to 70, given lack of much push of weak dry advection overnight. Previous discussion as of 230 PM EDT Saturday... A cold front was positioned just to the south of the forecast area. Isolated to scattered showers along this front will just barely clip the far southern sections of the area heading into the evening hours. Overnight, skies will trend to mostly clear across the north, and partly cloud south. Light winds, limited cloud cover, and a surface moisture will allow for the development of radiation fog across mainly the river and mountain valleys. This fog should burn off not long after sunrise Sunday. Low temperatures will average five to ten degrees lower than those realized this morning. Expect a mix of the mid 50s to near 60 degrees across the mountains with mid to upper 60s across the Piedmont. On Sunday, expect mostly sunny skies, calm or light and variable winds for the vast majority of the region. The exception may be the Northern Mountains of North Carolina and neighboring sections of the Grayson Highlands of Virginia. This area may experience enough low level convergence and differential heating where winds become south and advect back into the area some slightly higher dew point readings by the late afternoon. The result will be some isolated showers and storms that originate near ridgetop and then move slowly. High temperatures on Sunday will range from around 80 to the lower 80s across the mountains to the mid to upper 80s across the Piedmont. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... As of 255 PM EDT Saturday... Dry conditions expected Sunday evening under weak/relative high pressure. Increased low-level southerly flow should allow for a modest uptick in dewpoints along with some mid-level clouds east of the foothills of the Blue Ridge, but skies generally clear west. Lows range from the upper 50s to the mid/upper 60s. Sensible weather conditions Monday and Tuesday should be governed by falling 500 mb geopotential heights associated with northern stream closed low located north of Toronto by 12z Monday. Due to southerly low-level flow transporting higher dewpoints northward, air mass across the forecast area should be sufficiently enough unstable Monday to promote showers and thunderstorms; though it does begin the day with a convective cap around 800 mb. Secondly, I`ve noted a slower and slightly more westward shift in the best dynamic forcing Monday as well as a poorer-defined surface front in today`s guidance. These trends may reflect a condition where the best forcing aloft doesn`t necessarily line up with the time of peak heating and greatest convective instability. I`ve reduced PoPs areawide by around 10% to account for this, still in the high-Chance to borderline Likely range. What I believe unfolds is isolated to scattered showers/storms develop in the daytime heating along the mountains, becoming more numerous in coverage with the best height falls late afternoon into early evening but also weaker toward sunset. A few strong to locally severe thunderstorms producing gusty to at times damaging winds are possible due to lifted index values of -3 to -6 and relatively high downdraft CAPE values around 900 J/kg. With deep-layer wind shear values at or under 30 kts, storms may be loosely organized at best so any instances of severe weather should be more localized/transient. The overnight Day-3 Convective Outlook valid for Monday shows a Marginal Risk/5% severe probability for our central VA Piedmont counties, with general thunder indicated elsewhere. A general decrease in spatial coverage (slight chance level PoPs) are shown after midnight into the Tuesday early morning hours. Looking at highs topping out from the mid 70s at elevation, the lower/mid 80s west of the Blue Ridge to the mid/upper 80s elsewhere. By Tuesday, digging 500 mb vort from Monday over the Ohio Valley digs into the Carolinas - a feature which closes off in the 12z GFS over far western NC. It appears for Tuesday that the focus for showers and thunderstorms would be mainly east of the WV/VA border. Questions on the degree of instability in this area, with up to 2500 J/kg of surface-based CAPE, while the GFS is closer to 1000-1200 J/kg. NAM solution may be too warm and too moist, but even the GFS instability parameters should be sufficient enough to generate scattered thunderstorms, a few could be strong if the NAM instability values are correct. Storms should pose a localized heavy rain threat at least, given their slow moving nature (surface to 200 mb winds are under 20 kts) and high PWATs around 1.8". Storms should weaken and diminish with sunset Tuesday evening. Highs in the mid 80s to low 90s, warmest in the VA/NC Piedmont and Southside, with temps at higher elevations in the upper 70s with lows running in the 60s. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... As of 255 PM EDT Saturday... A bit less clarity on synoptic-scale details for the mid to late week period, due mainly to the newest wrinkle in the global guidance: the closed off mid-level low the GFS and the prior ECMWF run depict to be near North Carolina to start the period. Earlier solutions had showed the forecast area on the northeastern periphery of an amplified heat ridge over the center of the country, a pattern which may have been more favorable for convective complexes to develop in the Midwest and roll into the Ohio Valley/central Appalachians. Today`s runs show the mid-level low/trough on Wednesday shifting westward, weakening the heat ridge as it builds over the Ohio Valley and keeping the zone of faster mid-level winds well north of our area. Really two potential scenarios during this period: (1) warm to hot, humid and with potential opportunities for thunderstorms or thunderstorm clusters dependent on mesoscale details, or (2) hot, humid and largely dry. Due to the changes in the guidance today, it`s hard to predict which one may play out at this point. For that reason, will stay closer to blended solutions to minimize errors. However potential exists for change here, mainly on PoPs/Wx. Nonetheless, it appears that temperatures should trend above normal at least for late in the week. Indications are at some point into the weekend we do get into somewhat of a reprieve from the warm/humid conditions by the upcoming weekend with more northerly trajectories. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... As of 715 PM EDT Saturday... Frontal boundary will stall to our south across North Carolina into Sunday. High pressure will build across our area tonight into Sunday. With a closer proximity to the front, a few showers may move across North Carolina for next couple of hours. For the taf sites, VFR conditions will continue this evening into tonight. Overnight, look for a return of low level clouds with MVFR and low end VFR ceilings across the mountains. VFR ceilings are expected east of the crest of the Blue Ridge. Late night and early morning MVFR river/valley fog is expected along with some temporary IFR visibilities around daybreak. Any sub- VFR conditions will quickly trend to VFR Sunday morning. VFR conditions will continue into Sunday afternoon. Gusty northwest winds across the mountains this evening will decrease and become calm or light and variable overnight and remain that way through Sunday. Winds across the Piedmont will remain light and variable to calm through the forecast period. High Confidence in ceilings, visibilities and winds during the taf period. Aviation Extended Discussion... Sunday afternoon and evening light/calm winds and VFR conditions are still forecast. Some late night/early morning sub-VFR river/valley fog will be possible. Active weather returns to the forecast Monday into Tuesday as an upper trough become positioned across the area. Anticipate an increase in showers and storms, especially during the peak heating of the day. VFR conditions will prevail outside of the heavier showers and storms where temporary sub-VFR conditions will be the rule. Overnight, late night and early morning sub- VFR fog and stratus will be possible, especially over any area that received substantial precipitation. Wednesday into Thursday, the upper trough lifts northeast of the area placing us back into more of a summertime Bermuda High scenario. Anticipate a return to primarily diurnally based isolated showers and storms. Again, any sub-VFR conditions will be in association with the heavier showers and storms, and late night/early morning patchy river/valley fog. Confidence in the extended portion of the discussion is moderate to high on the weather elements occuring, but low to moderate on confidence of the timing of the specifics. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...DS NEAR TERM...DS/JH SHORT TERM...AL LONG TERM...AL AVIATION...DS/KK
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