Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/07/19


AREA FORECAST DISCUSSION
National Weather Service Albany NY
944 PM EDT Sat Jul 6 2019 .SYNOPSIS... A cold front will move south of the region tonight with the scattered showers and thunderstorms ending. A drier and less humid air mass will be over the region tomorrow with seasonable temperatures. High pressure will be in control Sunday night into the middle of next week with dry weather, moderating temperatures back above normal and fairly comfortable humidity levels. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... Updated at 945 pm. Have tweaked the grids to cover for a line of showers located near the cold front from western Massachusetts through the Capital District to the northern Catskills as of 930 pm. This batch of showers will sag southeastward with the front during the next few hours, with scattered showers getting down into the mid-Hudson valley and northwest Connecticut by around midnight. Dewpoints are still in the lower 70s immediately behind the front, but have fallen into the 50s over northern NY. This dryer air will gradually be working southward overnight, with dew points falling to the 50s as far south as the I-90 corridor by daybreak. Updated at 745 pm. Most of the showers have moved south and east of the area as of mid-evening, however the surface cold front is still located along a line from southern Vermont to near Albany down I-88 toward northeast Pa and is moving slowly southeastward. Dew points remain rather high across most of area, with readings mainly near or just above 70. Lower dew points are working southward across far northern NY and will overspread the area from the Capital District northward overnight. A few scattered showers will persist along and just behind the front through the rest of this evening, with coverage shrinking to below 30 percent area- wide by late evening, and to none by around midnight. Skies will clear north and west of the Capital District by midnight, and to the southeast during the early morning hours Sunday. Previous discussion is below. As of 406 PM EDT...A humid and tropical air mass will be over the region late this afternoon with sfc dewpts in the upper 60s to lower 70s. Prefrontal lines of showers and thunderstorms continue to form from the Capital Region and Berkshires north and west. The PWAT was 1.90" on the 12Z KALY sounding, as well as WFO OKX. WFO BUF upstream was 2.02", so we are looking at PWATS +2 to +3 STD DEVS above normal based on the GEFS. So some enhanced hourly rainfall rates of 1-2"/hr are possible. The steering flow is a bit stronger limiting widespread flash flood threat. Observational data shows over the models, west to southwest winds in the 700-500 hPa layer of 20-30 kts, so any convection should be moving along, and there is a small risk of training. Our thinking remains the same and isolated flash flooding is possible. Antecedent conditions are dry and 1-,3-,6-hr gridded FFG values are high. The severe threat continues to be contingent on maximizing CAPE, pcpn loading, and a few wet microbursts potentially forming. Mid-level lapse rates are poor. DCAPE values per the latest SPC RAP Mesoanalysis are 400-600 J/kg, and MLCAPE values are in the 1000-2000 J/kg range due to the high dewpts. 0-6 km bulk shear is 20-25 kts, so loosely organized deep convection is possible organizing into a line or two with some gusty or borderline damaging winds. A few severe thunderstorms may be possible. FQT lighting was kept in the forecast grids with any thunderstorms. We will monitor for an isolated severe threat. Hail does not look like a threat due to freezing levels around 15 kft AGL, weak lapse rates and taller and skinny sounding profiles. Based the latest CAMS the showers and thunderstorms should end quickly between 6-9 pm EDT from the Capital Region/Berkshires/Mohawk Valley north and west, and then between 9 pm - midnight south and east. A few showers may linger, shortly before or just after 06Z as the dewpt boundary lingers upstream of the main cold front. These showers will be near the mid Hudson Valley/NW CT. Sfc dewpts will fall into the upper 40s to mid/upper 50s from the Capital Region north and west by daybreak, and upper 50s to mid 60s south and east. There may be some patchy fog around the area with the greatest possibility along the CT River Valley in southeast VT. In the cold advection in the wake of front, lows will fall back into the 50s to mid 60s. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... Sunday...A splendid and delightful finish to the 4th of July holiday weekend is expected with a drier air mass continuing to build into the region from southeast Canada and the Great Lakes Region. Low-level cold advection will continue with H850 temps dipping into the +12C to +15C range from northwest to southeast across the forecast area. The subsidence from the ridge building in should yield mostly sunny conditions. Sfc dewpts will be mainly in the 50s. Highs will be near seasonal normals in the upper 70s to lower 80s in the valleys, and upper 60s to mid 70s over the higher terrain. North winds will generally be 5 to 10 mph. Sunday night...A beautiful early July night with mostly clear/clear and cool conditions. Some radiational cooling is expected with clear skies and the winds becoming calm. Lows will drop to the mid 40s to lower 50s over the southern Adirondacks, Lake George/Glens Falls area, and southern VT, and mid to upper 50s from the Mohawk Valley/Capital Region south and east. Monday-Monday Night...A great stretch of fair weather continues for early July with the sfc anticyclone ridging eastward from the central/eastern Great Lakes Region over NY and New England. Heights will begin to rise aloft by Mon night. Temps will be near seasonal normals with 70s to lower 80s for highs, and 50s for lows will very comfortable humidity levels. && .LONG TERM /TUESDAY THROUGH SATURDAY/... High pressure at the surface with ridging building aloft will bring mostly clear skies for Tuesday and Wednesday. Temperatures will start out near normal for Tuesday, but warm slightly under the influence of the upper level ridge for Wednesday. Humidity levels will be fairly comfortable both days, although Tuesday gets the nod as the drier day. A short wave trough riding the northern border will approach the region on Thursday and cross over the area on Friday. Chances for showers and thunderstorms increase to likely levels on Thursday, pulling back to the chance category for Friday. With clouds, showers, and cooler temperatures about, temperatures both days will edge back to near normal. Some indications that precipitable water values could increase to about one standard deviation above normal with the passage of the trough. So some heavier showers/thunderstorms possible, mainly creating minor ponding issues. From the vantage point of one week out, next Saturday looks dry with weak high pressure building in. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... A cold front located near ALB this evening and will sag southward to the south of POU by daybreak Sunday. Scattered showers will persist near ALB/PSF/POU through the rest of this evening near the front, before ending overnight. Conditions will be mostly VFR tonight, except for brief periods of MVFR conditions near any showers this evening. Skies will clear late tonight with sunny VFR conditions expected during the day Sunday. Winds will be light and variable, becoming light north- northwesterly overnight, then north-northwest at 5 to 10 kts on Sunday. Outlook... Sunday night through Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: Moderate Operational Impact. Chance of SHRA. Thursday: High Operational Impact. Likely SHRA...TSRA. && .FIRE WEATHER... A cold front will move south of the region tonight with the scattered showers and thunderstorms ending. A drier and less humid air mass will be over the region tomorrow with seasonable temperatures. High pressure will be in control Sunday night into the middle of next week with fair and dry weather. The maximum RH values tonight will be in the 85 to 100 percent range, and then lower to 30 to 50 percent Sunday afternoon. Expect the RH values to recover the 75 to 100 percent Monday morning. The winds will shift to the northwest or north at 5 to 15 mph tonight, and will continue to be northerly at 5 to 10 mph Sunday afternoon. The winds will become light to calm Sunday night. && .HYDROLOGY... The cold front late this afternoon into tonight will interact with a very humid and moist airmass with surface dewpoints in the upper 60s to lower 70s with PWAT values +2 to +3 STD DEVs above normal in the 1.7-2.0+ inch range. Scattered showers and thunderstorms will continue into the early evening ahead of the front. There is a threat for urban and poor-drainage flooding, as well as isolated flash flooding if multiple rounds of convection occur repeatedly over one location. Basin average QPF of 0.25 to 0.75 inches are possible with locally higher amounts ranging from 1 to 2+ inches. The flash flooding threat will be lessened tremendously by the dry antecedent conditions. A period of dry weather will occur Sunday through Wednesday. Please visit our Advanced Hydrologic Prediction Service /AHPS/ web page for specific area rivers and lakes observations and forecasts. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Wasula NEAR TERM...MSE/Wasula SHORT TERM...Wasula LONG TERM...OKeefe AVIATION...MSE/OKeefe FIRE WEATHER...Wasula HYDROLOGY...BGM/Wasula
Area Forecast Discussion
National Weather Service Bismarck ND
955 PM CDT Sat Jul 6 2019 .UPDATE... Issued at 948 PM CDT Sat Jul 6 2019 Eliminated pops for the rest of this evening. Did keep some small pops far southwest and south central late tonight into Sunday morning as warm advection increases late. Made some minor adjustments to sky cover, increasing low clouds southwest late tonight into Sunday morning. Otherwise no significant changes to the going forecast. UPDATE Issued at 549 PM CDT Sat Jul 6 2019 No significant changes for the late afternoon update. Isolated convection remains just north of the border, over southern Saskatchewan. Latest CAMS continue to show isolated convection over the west and central through early evening. Looking at forecast soundings, it appears areas north of Minot and Williston would have the best chance of a stray shower or thunderstorm, with enough of a cap to inhibit convection over most of western and central ND. Can`t completely rule out a shower or two so will maintain the slight chance pops through early evening. Otherwise, populated latest sensible weather elements and blended to early evening values. We did bump up sky cover a little overnight as there are some indications of lower stratus developing after midnight, but little agreement on where. RAP forecast soundings indicate elevated CAPE remaining over western into north central ND through the night, but with no shortwave to spark convection, and not sure increasing warm advection will be enough to start convection either. For now will leave the forecast as is, dry after midnight, after evening convection ends. The exception being a slight chance in the far southwest and south central late, closest to the increasing warm advection. && .SHORT TERM...(This evening through Sunday) Issued at 216 PM CDT Sat Jul 6 2019 Afternoon satellite imagery across the region shows cumulus has developed across much of western and central North Dakota. So far, it has not had too much vertical development, though short term models still hint at the potential for at least isolated showers and thunderstorms this afternoon. Will continue to mention a slight chance in the forecast, especially in the western half of the forecast area. Rain chances should wane tonight as we lose heating. Fog has developed over the past couple of nights, so took a close look at that potential for tonight again. The HRRR doesn`t show much in the way of visibility restrictions, and with the surface high moving to our east, wasn`t confident enough to add a mention yet. Thunderstorm chances for Sunday look rather limited again, but can`t totally rule isolated development in the afternoon. Models continue to show a precipitation signal, and with all the subtle waves in in the upper flow, will hang onto the small pops we already have in the forecast. .LONG TERM...(Sunday night through Saturday) Issued at 216 PM CDT Sat Jul 6 2019 The better rain chances come early in the long term period. Thunderstorms across northeast Montana are expected to move towards western North Dakota Sunday night. The latest SPC Day 2 outlook brings the Slight Risk just across the Montana / North Dakota border. Have gone with the highest pops in the northwest, with lesser chances in the south central. The chance for thunderstorms continues Monday as an H5 waves moves across the Northern Plains. A surface boundary will also be making its way across the state, with good instability ahead of the front. Deep layer shear remains a bit in question, but overall the severe weather threat still remains. Will continue to mention the possibility in the Hazardous Weather Outlook, and we have already begun messaging the possibility in our other graphics. Heavy rain will also be a concern and that is already in our messaging too. Thunderstorm chances continue Tuesday, especially in eastern parts of the forecast area. A break in the thunderstorm chances still appears reasonable mid-week with an H5 ridge building into the region. Rain chances become a bit more challenging to pin down later next week with waves running over the top of the ridge. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 948 PM CDT Sat Jul 6 2019 VFR conditions to begin the forecast period. Expect VFR with scattered to broken ceilings 6-8k ft this evening. Late tonight forecast models indicate increasing low level moisture with latest iterations of the short term models hitting the southwest rather than south central. For now will keep ceilings VFR but may introduce some MVFR cigs with the 06Z TAF issuance, most likely just for KDIK to begin with. If stratus does not develop, there could still be a period of MVFR ceilings with a developing cumulus field, most likely at KDIK and/or KBIS. By afternoon expect VFR conditions. Isolated thunderstorms are possible Sunday afternoon, but too far out to mention at any one TAF site at this time. South to southeast surface flow is expected through the TAF period, with gusts up to 25kts Sunday afternoon. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...CK LONG TERM...CK AVIATION...TWH
Area Forecast Discussion
National Weather Service Denver/Boulder CO
800 PM MDT Sat Jul 6 2019 .UPDATE... Issued at 800 PM MDT Sat Jul 6 2019 Storms are rolling east/southeast from Wyoming, but have recently weakened a little, perhaps because they`re running into slightly cooler boundary layer air. We still think there is a threat of severe thunderstorms roughly along/north of a line from Wellington to Akron, with the highest probabilities of storms over the northern border area through the midnight hour. The increasing low level jet could be the kicker of additional storm development over the northeast plains late this evening. We`ll look at possible severe thunderstorm watch extension and expansion to the east. Otherwise, we were able to clear more of the Denver area and Palmer Divide from the severe thunderstorm watch, as 00Z sounding shows airmass just a bit too capped to support surface based strong/severe convection. There is one thing that could still pop a few strong/severe storms along the Front Range, and that would be an outflow boundary pushing out of the Wyoming/far northern Colorado convection. It`s a small chance, but a chance nonetheless since we did not tap into much if any of the 1000-1500 J/kg MLCAPE this afternoon along the Front Range. UPDATE Issued at 546 PM MDT Sat Jul 6 2019 Storms have been paltry so far, and a look at the latest aircraft data departing DIA shows a pretty strong stable layer near 725 mb that is effectively capping off the I-25 Corridor. Will be nice to see the 00Z Denver sounding. There were still a few storms on the plains and trying to get going over the mountains, but the main chance of any severe weather is shifting to the north and east. There is some threat with the storms firing over Morgan county and spreading eastward, but the main threat of more organized severe weather appears to be shaping up from the storms dropping east/southeast from Wyoming. These are severe already, and should try to organize into a Mesoscale Convective System (MCS) as they feed on an intensifying low level jet this evening. Most of these should remain north of a line from Wellington to Akron, and will be most likely near the Wyoming border cutting through the northeast corner of the state. Right moving severe supercells with very large hail could definitely be in the picture given existing MLCAPE near 1500-2000 J/kg and stronger shear profile to the north. We`ll keep higher PoPs and severe risk there, but have dropped the chance of storms in/around Denver. && .SHORT TERM...(This evening through Sunday) Issued at 322 PM MDT Sat Jul 6 2019 Storms developing over southern Jefferson County at this time. Two separate areas focused on by the High Res models this afternoon and evening. The first area will around the Denver area including points mainly south and east. Main concern will focus for severe will be around this areas. Weak cyclonic circulation as well around Denver which could enhance the potential for severe thunderstorms. RAP forecast soundings indicate CAPEs around 1200 j/kg with favorable directional shear as well. Precipitable water values still close to 0.80 inches as well. Later this evening, another area of thunderstorms is forecast clip the northeast corner of the forecast area around 03z. Higher CAPES/greater shear in this area. Potential for a weak tornado or two there as well. Most of the cwa has been under a jet max this afternoon which appears to have capped some thunderstorm development, but this will shift eastward this evening which aid deep convection. On Sunday, the flow aloft will remain southwesterly with continued potential for thunderstorms in the afternoon. CAPE values still healthy so potential exists for another period of severe thunderstorms with CAPES 1400 around Denver to 2400 j/kg over the northeast plains. Higher CAPE and weaker shear, but temperatures will be warmer with highs around 85. Expect the storms on Sunday to be more pulse type cells. .LONG TERM...(Sunday night through Saturday) Issued at 322 PM MDT Sat Jul 6 2019 Medium range models continue to show a couple more days of moist southwesterly flow aloft which will set up each afternoon for rounds of afternoon and evening thunderstorms. Monday looks like it will be the last afternoon of highest coverage of thunderstorms as the flow aloft turns more westerly on Tuesday that drops the mid-level moisture a little bit. The GFS is stronger than the ECMWF with the drying effects, so Tuesday and Wednesday will still need the mention of at least some afternoon thunderstorms. Cross sections from the NAM show strong drying Tuesday morning with flow at mid levels around 20 knots, but by Wednesday night a low level surge of northeasterlies and increasing moisture appear to be on their way. The ECMWF backs up this scenario. With all of the ingredients necessary for storm formation in place over northeast Colorado through the majority of the week, the cycle of afternoon and evening thunderstorms will remain in the forecast. Temperatures will reach the mid 80s to mid 90s each afternoon. Each day will need to be assessed with regard to the threat of heavy rainfall. By the end of the week, the upper ridge looks to be centered over the Four Corners area which typically leads to weak flow aloft across northern Colorado. Weak flow patterns and slow moving thunderstorms go hand in hand, so if precipitable water values increase, then the threat of heavy rainfall will also increase. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 800 PM MDT Sat Jul 6 2019 Storm threat is low over the Denver area airports due to a stable layer noted on the aircraft data moving in/out of Denver and the 00Z Denver sounding. We still see a small chance of thunderstorms if an outflow boundary from the southern Wyoming/far northern Colorado convection moves into the Front Range. Otherwise, low level moisture could slip back into KDEN late tonight/early Sunday with redevelopment of a Denver cyclone or convective push from the the north and east. So there`s a risk of stratus and IFR/MVFR ceilings 11Z-15Z. Scattered thunderstorms possible Sunday afternoon after 21Z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Barjenbruch SHORT TERM...Cooper LONG TERM...Dankers AVIATION...Barjenbruch
Area Forecast Discussion
National Weather Service Cheyenne WY
535 PM MDT Sat Jul 6 2019 .SHORT TERM...(This evening through Sunday) Issued at 219 PM MDT Sat Jul 6 2019 A severe thunderstorm watch is now in effect for most of Southeast Wyoming (minus Carbon County) and entire Nebraska Panhandle through 9pm. Main hazards will be large hail (upwards of golfball to baseball size), damaging 60-70 mph winds, and a tornado or two could be possible. In addition, localized heavy rainfall and storm training could cause flash flooding concerns. Please stay alert through the afternoon and evening as storm hazards develop. Storms will dissipate and shift east through the mid to late evening hours. MLCAPE instability continues to grow upwards of 1500-2000 J/Kg with some slight implied capping in place per mesoanalysis and latest satellite trends. The first round of storms initially fired over the higher terrain now have orphaned anvils that are crossing into the High Plains. Of interesting note is the dissipating anvil over Laramie County is suppressing the cumulus field below while forming a localized boundary moving east. This boundary has cleared out northwest Laramie County well for greater insolation. However, this also veered the winds almost westerly in this local area. Will need to see if greater S/SE flow can get re-established in this area. Farther north and east, low-level winds remain backed to SSE/SE, especially across the NE Panhandle with some east winds near Scottsbluff. Effective deep layer shear remains near 40 knots along the Laramie Range with lower values in NE Panhandle. However, expect higher amounts of shear over NE Panhandle next 6 hours. All of these factors combined, deep robust rotating updrafts will be likely this afternoon and evening supporting large hail. Tornado potential continues to look marginal as low-level wind shear remains below 100 m2/s2 but localized enhancements near boundaries or isolated supercells could perhaps ingest enough helicity for low-level vertical stretching. A weak/brief tornado or two can`t be fully ruled out. Storm mode should initially be discrete to semi-discrete supercells that grow upscale into a cluster or possibly into a cold pool balanced complex as they move east into NE Panhandle. Risk for localized flooding could be maximized in NE Panhandle due to clustering and possible training of storms with mixing ratios of 10-12 in place. Slightly greater ridging will occur Sunday but a marginal risk for severe storms is also in place for portions of the area. H5 winds will be lower along with deep layer shear being weaker. However, compensating instability could still help decent storm updrafts for hail and wind hazard risks. .LONG TERM...(Monday night through Friday) Issued at 310 AM MDT Sat Jul 6 2019 Widely sctd convection ending over the CWA Monday night but returning again Tuesday afternoon as a shortwave moves east across the region. A few strong storms possible though better dynamics look to be more to the north. After that a somewhat drier weather regime expected to set up over the region as an upper high builds over the southern Rockys Weds and remains there for the rest of the week. Weak disturbances riding over the top of the high will still set off some mainly afternoon and evening showers and storms most days but should be more on an isolated basis. Temps generally close to seasonal averages. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 524 PM MDT Sat Jul 6 2019 Thunderstorms have begun across the high terrain between KRWL and KLAR. Storms will continue to move eastward toward the NE Panhandle terminals after 00Z. Gusty winds and reduced visibility can be expected with these storms into this evening with KBFF and KSNY most at risk for thunderstorm activity. After the storms move out of the area, lower ceilings may creep into the NE Panhandle early Sunday morning. The HRRR has been bringing in lower ceilings and visibility to KCYS after 08Z the last few runs. Will continue to monitor these trends into this evening in case a further lowering of flight category in the TAF is needed. && .FIRE WEATHER... Issued at 217 PM MDT Sat Jul 6 2019 Limited fire weather concerns today with area showers and thunderstorms across much of the area and higher then normal relative humidity values. One concern will be localized fire starts from lightning activity today but most thunderstorms should have some rain opposed to dry lightning situation. Isolated elevated fire weather conditions will occur Sunday into Monday mainly across Carbon County due to elevated winds and humidity values falling to 20 percent. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...JSA LONG TERM...RE AVIATION...MB FIRE WEATHER...JSA
Area Forecast Discussion
National Weather Service North Platte NE
652 PM CDT Sat Jul 6 2019 .SHORT TERM...(This evening through Sunday night) Issued at 326 PM CDT Sat Jul 6 2019 Atmosphere again in recovery mode this afternoon in the wake of the latest MCS that crossed the area last night. A weak surface low is noted across north central Nebraska, with bands of stratocumulus clouds in areas of weak convergence across the region. An isolated weak thunderstorm could develop in one of those areas of weak convergence, but the better threat of thunderstorms will come later this evening and overnight. HRRR and several other Hi-Res HREF members organize thunderstorms into a small complex across the central and southern Panhandle early this evening. The storms then track east across portions of the southern Sandhills and southwest Nebraska late this evening and overnight. Some strong wind potential with the cluster as well as locally heavy rainfall. Will carry a swath of likely pops where the system is expected to track with 40 or less pops elsewhere. Similar set up on Sunday with southeast moist low-level flow aiding in destabilization across the western High Plains Sunday afternoon and evening. This should once again lead to scattered afternoon thunderstorm development, with the activity possibly moving into western Nebraska Sunday evening. Otherwise southeast winds will increase Sunday as pressure falls across the Western High Plains. Gusts up to 30 mph are possible across portions of the Sandhills and north central Nebraska. The increased wind will aid in better mixing with highs into the mid 80s across western Nebraska. .LONG TERM...(Monday through Saturday) Issued at 326 PM CDT Sat Jul 6 2019 The start of the upcoming week will be unsettled. Upper level ridging will be suppressed well south as an upper level trough moves east across the Central and Northern Plains. This will lead to an uptick in shower and thunderstorm chances Monday and Tuesday. By the middle and latter parts of the week, GEFS and ECMWF build upper level ridging into the four corners region and much of the Central and Southern Plains. This will spread a warm layer aloft across much of the region which will limit rain chances. Above normal temperatures are also expected, with highs climbing into the lower 90s by Friday and Saturday. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 643 PM CDT Sat Jul 6 2019 Thunderstorm chances increase later this evening into the overnight. At this time the greatest chance for thunderstorms will be across western and southwest Nebraska, mainly south of KVTN. MVFR conditions are possible mid morning, mostly across southwest Nebraska, with ceiling heights increasing in the afternoon. Winds will increase in the afternoon out of the south. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Taylor LONG TERM...Taylor AVIATION...Gomez
Area Forecast Discussion
National Weather Service Memphis TN
951 PM CDT Sat Jul 6 2019 .UPDATE... An upper trof remains over the Mid-South this evening. As a result, showers and thunderstorms have developed over West Tennessee near the Tennessee River as well a few isolated ones over Eastern Arkansas. The HRRR shows the convection near the Tennessee River continuing to sink south into Northeast Mississippi during the overnight hours. Will update to adjust POPS accordingly. Rest of the forecast looks good. KRM && .DISCUSSION... /issued 319 PM CDT Sat Jul 6 2019/ Another warm summer day is in progress across the Mid-South. Some convection has initiated already this afternoon, mainly across areas east. Anticipate more showers and thunderstorms to pop up through the evening hours. Feel most of this will remain across eastern portions of the FA, given the location and orientation of the upper trof, from NE to SW over the area. The latest H5 analysis also shows the upper ridge currently located over south Texas. This feature will move east toward the Mid-South, bringing warmer and slightly drier conditions by midweek. After a dry night with temperatures down into the mid to lower 70s, Sunday will be another nice day with highs a few degrees warmer than today. The upper trof moves to the south, so afternoon thunderstorm activity chances appear more favorable across southern locales of the FA on Sunday afternoon. Similar conditions will prevail on Monday as the upper ridge begins to nose back into the region from the west. As a result, some locales may not see any rain for a couple of days as chance POPs will not return areawide until Wednesday afternoon. The big story from Monday through midweek will be the temperatures. With the ridge moving back into the region afternoon highs will gradually warm into the mid 90s by Wednesday afternoon. This will allow for heat indices in the triple digits, particularly on Wednesday when values will warrant monitoring for possible Heat Advisory issuance. The meandering upper ridge will continue to meander by late in the week. The feature retrogrades westward yet again on Thursday, allowing better diurnal convection chances each day through the weekend as northwest flow returns aloft. Temperatures will be on a cooling trend by late week as highs return to the lower 90s each day. Interestingly, at least one of the long term models develops some tropical activity over the Gulf of Mexico next weekend from the upper trof currently over the Mid-South. While there is very little agreement between the models at this time, at least one solution brings rain to the area from this system for next weekend. This interesting scenario will warrant monitoring as the week progresses. ZDM && .AVIATION... Most of the SHRAs and TSRAs are on the periphery of the Mid-South this evening so the very near term looks fine at the TAF sites. Later this evening the CAMs are developing convection across West TN and later moving it into North MS. For now will go with VCSH at KMEM/KMKL and KTUP and monitor. TSRA chances should diminish with loss of heating overnight. OTRW expect VFR conds through the period. Best chance of afternoon TSRAs on Sunday will be at KTUP so included a VCTS there. Winds will generally be light and mainly from the west and northwest. SJM && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$
Area Forecast Discussion
National Weather Service Nashville TN
847 PM CDT Sat Jul 6 2019 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... For a better set of terms, numerous shwrs with sct tstms "rounding the bend" across mid state sw counties as mid evening hrs progress per association with weak upper level low circulation aloft. Latest HRRR model shows this trend continuing thru remainder of evening hrs. Updated suite of forecast products to reflect this. Remainder of forecast continues to be on track. && .AVIATION... 00Z TAF DISCUSSION. CKV/BNA/MQY/CSV...Per above mentioned unstable wx pattern, confidence of shwrs forming at terminals not high enough to mention prevailing, so mentioned VCSH at CKV/BNA/MQY. Not enough confidence presently to mention even VCSH CSV as current shwrs are far W of CSV. Confidence of any shwrs even in vcnty of CKV/BNA/MQY terminals wanes after 07/08Z, 07/05Z CSV, but terminal MVFR fog formation possible thru 17/12Z. From 17/15Z-17/24Z with convection initiation diurnally driven, iso to sct shwrs/tstms could once again form, but confidence of formation at individual terminals not great enough to mention prevailing. Thus will transition from VCSH 07/15-16Z to VCTS 07/17Z-07/24Z CKV/BNA/MQY. Per orographic influences and expected deeper overall low level moisture around CSV, VCSH 07/14Z should transition to VCTS tstms around 07/16Z. Initial light W sfc winds will veer NW thru 07/24Z. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......31 AVIATION........31
Area Forecast Discussion
National Weather Service Pueblo CO
823 PM MDT Sat Jul 6 2019 .UPDATE... Issued at 813 PM MDT Sat Jul 6 2019 Latest radar, satellite, and SPC mesoanalysis trends suggest that only weak instability remains across the forecast area, but capping is preventing convective growth in most areas. A few thunderstorms persist in Baca and Prowers Counties where the best instability is present, but weak shear. Elsewhere, the forecast area is mostly dry with very isolated rain showers and residual outflow boundaries. Expect precipitation coverage to remain isolated before becoming dry by midnight. ~Line UPDATE Issued at 509 PM MDT Sat Jul 6 2019 Updated precipitation forecast for this evening to account for latest satellite, radar, and hi-res model trends. Much of the area should only see isolated to scattered coverage, spreading east through the evening. While cloud cover has limited the development of instability across much of the area, up to around 1000 j/kg is analyzed over the Pikes Peak region, where deep layer shear is also favorable. Therefore, still expect the possibility of a strong to low-end severe storm there early this evening. Elsewhere, weak instability and shear will limit activity to showers and weak thunderstorms this evening. ~Line && .SHORT TERM...(This evening through Sunday) Issued at 248 PM MDT Sat Jul 6 2019 Currently...A number of slow-moving showers and storms across the southern Sangre de Cristo mountains this aftn, as well as across the central mts in the vicinity of Monarch Pass. This has produced abundant cloud cover for much of the forecast area save for the far eastern plains near the KS border, keeping temps somewhat subdued today. Highs so far as of 3 pm have been in the 60s and 70s for most locations, though LHX and LAA have seen a good amount of sun and have warmed up into the lower 80s. Very little change to the ongoing upper pattern, with a ridge of high pressure centered over TX and OK, and a broad upper trough over the western third of the US. This will keep southwest flow aloft in place over the Four Corners, with moisture pouring into the cwa from the south. Tonight...Rather meager storm activity across the region this afternoon, and the latest runs of the HRRR indicate that although activity will likely linger until around midnight, it will not be as widespread as initially thought. There will be a wave that develops over the southern Front Range and rolls east across the plains between 6 and 7 pm, but after that things should stabilize and allow partially clearing skies. Look for lows in the 40s for the high valleys, and 50s to around 60F for the plains. Tomorrow...With a somewhat stagnant upper pattern, look for a repeat tomorrow with respect to convection. However, do not feel that there will be as much lower clouds along the I-25 corridor to start the day. There will already be a healthy pool of low level moisture to tap into, and with greater heating expected, tomorrow may be the day for widespread convection over the higher terrain by midday, then sweeping across the plains through the afternoon and eve. Once again, flash flooding will remain a strong concern for area burn scars. Latest NAM run indicates 1500-2500 j/kg of CAPE over the far eastern plains between 21z-03z, and SPC has painted all of the plains within the Marginal category for severe weather. So, little to no cloud cover tomorrow morning will mean quicker and more intense heating, which in turn may mean that the potential of the moisture pool will be realized. Time will tell. Plan on highs in the 70s for the high valleys, and in the 80s across the plains. Moore .LONG TERM...(Sunday night through Saturday) Issued at 248 PM MDT Sat Jul 6 2019 Precipitable waters remain high across southern CO through Sunday evening with thunderstorms continuing into the evening across the mountains and plains. With weaker deep layer shears, threat for storm organization and severe thunderstorms appears lower, but threat for burn scar flash flooding will remain elevated. We appear to lack much of a trigger besides surface heating, as low level flow becomes more southerly (putting best upslope component into the eastern San Juans), and PV fields look rather nondescript. However low level jet across the plains east of the surface trof axis will also likely provide some convergence for thunderstorms into the evening with a isolated nocturnal thunderstorms possible past midnight across far eastern areas. Next shortwave will be riding up western side of the southern U.S. upper ridge on Monday. This will bring better forcing for thunderstorms across the mountains during the afternoon as well as some drying into southwest portions of the area behind the feature. Overall, looks like the thunderstorm focus region will shift north and east this day. Still some healthy CAPE out near the border with values 1500+ J/kg but deep layer shears are only running around 20- 25 kts, so main thunderstorm risks will be heavy rain and winds, though some sporadic hail with any initial intense updrafts will be possible before they become precipitation loaded. Thunderstorms will push eastward into KS during the evening, with a relatively quiet night for Monday night. Tuesday and Wednesday still look like relatively quiet dry days as upper high rebuilds northward and establishes itself across southern CO/northern NM. Pops should decrease quite a bit over the area with mainly isolated thunderstorms across the mountains. Upper trof swinging through the northern Rockies into the northern high plains Tuesday night sends a cold front through the eastern plains Tuesday night/early Wednesday which will increase moisture and may nudge up precipitation chances for Wednesday afternoon across the plains and Pikes Peak region for Wednesday afternoon and evening. Depending on extent of low level moisture, there could be plenty of CAPE this day as well as upslope, but shear may be lacking with the upper high building over the region and there may be a cap to overcome as well. Either way, convection may not be very widespread this day. Temperatures will heat up for Thursday and Friday with diurnal thunderstorm chances both days given residual moisture caught within the upper high. Another upswing in thunderstorms will be possible next weekend as Pacific moisture gets drawn up from the south. -KT && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 248 PM MDT Sat Jul 6 2019 VFR conditions expected across much of the forecast area over the next 24 hrs, including the three main TAF sites of KCOS, KPUB and KALS. Showers and storms will develop over the higher terrain this aftn, then potentially roll across the adjacent plains areas affecting the TAF sites between 21-23z. Storms should clear out of the San Luis Valley by 03z, while showers will linger along the I-25 corridor until around 07z before exiting to the east. Conditions will become MVFR to at times IFR under heavier showers and storms. The eastern plains are under a Marginal threat for severe weather, increasing to Slight over the Palmer Divide and north. One or two of the storms that develop will be capable of producing larger hail of an inch or greater in diameter, and wind gusts in excess of 60 mph. Look for a repeat tomorrow with even more moisture available and a Marginal threat for severe weather across the eastern plains. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...LINE SHORT TERM...MOORE LONG TERM...KT AVIATION...MOORE
AREA FORECAST DISCUSSION
National Weather Service Charleston WV
1023 PM EDT Sat Jul 6 2019 .SYNOPSIS... Very warm and humid weather through the weekend, with mainly afternoon and evening showers and thunderstorms. A cold front brings relief for early next week. Hot and muggy by midweek. && .NEAR TERM /THROUGH SUNDAY/... As of 1023 PM Saturday.. Modified POPs through the overnight period to continue reflecting latest radar and model trends. Temperatures were also tweaked to mirror observations from around the region this evening. As of 745 PM Saturday... Thunderstorms in the area have tarnished temperatures across the region, so tweaked them down a few degrees to better align with current observations. Also touched up POPs for our southeast Ohio Counties to reflect storms moving in from WFO ILN`s territory. As of 200 PM Saturday... Ribbons of theta-e advection should serve as the primary focus for convection thru early aftn and have coded POPs based on RAP depiction of these features. An uptick on storm motion is expected thru the afternoon with mean flow increasing a hair, as already evident with the recent radar returns. Meanwhile, a front will be sagging south this afternoon, taking until early this evening to slip into southeast OH. This will eventually take over as the main forcing for ascent, with convection becoming more numerous along and ahead of the boundary. PWAT values are progged to reach or eclipse 2" as deep moisture pools in the vicinity of the baroclinic zone by late afternoon/early evening. This, combined with a deep warm cloud layer, would mean for very efficient downpours with very heavy rain rates. There is the potential for a period of training this evening from portions of southeast OH and into northern WV which would further exacerbate the flash flood threat. After collaboration with neighboring offices, I have elected to hoist a Flash Flood watch thru late tonight across the northern WV Lowlands and northeast WV mountains, where FFG is lowest. There is concern that, even in portions of southeast OH where guidance is a bit higher, that isolated high water is possible. Front will settle into central portions of the CWA late tonight with coverage of activity gradually decreasing. The front will gradually settle south on Sunday with convection chances highest across the southern third of the CWA. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... As of 245 PM Saturday... Where the cold front resides at the start of the short term will be key in terms of PoPs Sunday evening. Guidance suggests rain tapering off from west to east on Monday as high pressure expands over the Great Lakes region. Higher elevations will likely see showers and storms continue through the day on Monday before beginning to relish in the drier weather associated the encroaching high on Tuesday. Temperatures gradually rise through the period, especially by Tuesday as shortwave ridging and height rises come into play. At which time, we can expect to see afternoon highs in the upper 80s (lowlands) and low- to mid-70s (mountains). && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... As of 245 PM Saturday... High pressure remains in control on Wednesday, with afternoon temperatures maxing out in the low 90s. This is in response to a warm front surging northward ahead of the next upper trough sinking down from the upper Plains. Shower and thunderstorm chances increase by late Wednesday night and remain prominent overhead through the end of the work week once the cold front is progged to cross through Central Appalachia. Quiet weather is then suggested to return for the weekend. Temperatures remain hot through the long term with no sign of relief from higher dew points, resulting in continuing muggy conditions. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... As of 800 PM Saturday... Unsettled weather continues this evening with numerous showers and storms crossing through the region. As has been the case the past few days, VFR will hold at all terminals that reside outside of the storms, while briefly falling to sub-MVFR beneath any heavy storm. Handled this with TEMPO groups at all TAF sites from 00-04Z when the best organization of storms are expected. The overnight period of the forecast will encompass a hodgepodge of flight restrictions due to low stratus and fog development. A cold front is progged to sink southward into Central Appalachia through the night, bringing an end to showers and storms. However, quickly behind the conclusion of precip, the likelihood for fog increases, especially at terminals that encounter TSRA. During the predawn hours, low stratus is expected to filter into the northern half of the forecast region, plaguing EKN, CKB, and PKB with IFR and possibly LIFR cigs. Low ceilings will struggle to scatter Sunday morning, but should improve by midday with daytime heating and mixing. Another round of showers and storms are likely to impact terminals Sunday afternoon as the front sluggishly pushes southward towards the Carolinas. VCTS is currently displayed for many of the sites towards the end of this current TAF period, with refinement to timing and intensity of storms likely with future forecasts. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY... FORECAST CONFIDENCE: Medium to High. ALTERNATE SCENARIOS: Timing and intensity of low stratus and fog may differ from forecast Sunday morning. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE SUN 07/07/19 UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11 EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07 CRW CONSISTENCY H H H H M H H H L L M L HTS CONSISTENCY H H H H H H L M M M M M BKW CONSISTENCY H H H H H H M M M M L L EKN CONSISTENCY H H H H H H L H L L L L PKB CONSISTENCY H H H H M H H H H L L L CKB CONSISTENCY H H H M L H L L L H H M AFTER 00Z MONDAY... IFR possible in fog and stratus Monday and Tuesday mornings. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...Flash Flood Watch until 5 AM EDT Sunday for WVZ009>011-017>020- 028>032-039-040-521>523-525-526. OH...None. KY...None. VA...None. && $$ SYNOPSIS...30/MEK NEAR TERM...30 SHORT TERM...MEK LONG TERM...MEK AVIATION...MEK
Area Forecast Discussion
National Weather Service San Angelo TX
645 PM CDT Sat Jul 6 2019 .AVIATION... /00Z TAFS/ VFR conditions are expected to remain in place for the next 6 hours or so. Meanwhile, scattered thunderstorms will continue until sunset near KSJT and west of KABI. However, due to little storm motion, these storms stand little chance of impacting either terminal unless they develop directly over it. Then, KJCT and KSOA will drop into the MVFR ceiling categories around 11z. VFR ceilings will return by late morning and also for the afternoon hours. && .PREV DISCUSSION... /issued 257 PM CDT Sat Jul 6 2019/ SHORT TERM... (Tonight and Sunday) ..Big Country Rain This Evening... The potential for Big Country rain will continue into this evening. Plus, some of our western counties may receive rain Sunday afternoon. The main convection driver this afternoon, across our Big Country counties, is an outflow boundary, which moved into Texas from the north. This type of convection is very challenging to forecast. Nevertheless, short-term, high- resolution, models are doing a fairly. The HRRR ends this convection by 10 PM CDT this evening. Thus, continuing low PoPs, for the Big Country, looks reasonable. For Sunday, convection to our west may move into our western counties, during the afternoon. Thus, 20 PoPs for that area also looks reasonable. LONG TERM... (Sunday Night through Saturday) ..Possible Rain Western Counties... Aside for possible rain, over our western counties, during the afternoon and early evenings through Monday, the long term forecast remains dry and hot. Temperatures will likely continue to warm slightly each day, and by Monday afternoon highs around 100 will likely be common, across West Central Texas. Highs in this range look likely, at least into mid week. Then, slightly cooler afternoon highs may occur, as the center of high pressure aloft moves out of Texas and over northern New Mexico and southern Colorado. && .PRELIMINARY POINT TEMPS/POPS... Abilene 73 95 74 95 / 10 0 10 10 San Angelo 72 96 73 97 / 10 0 10 10 Junction 71 95 73 96 / 0 0 0 0 Brownwood 72 96 73 97 / 10 0 0 5 Sweetwater 72 94 73 95 / 10 10 20 20 Ozona 71 90 72 93 / 5 10 10 10 && .SJT WATCHES/WARNINGS/ADVISORIES... None. && $$ 41