Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/18/19

National Weather Service Albany NY
1027 PM EDT Mon Jun 17 2019 .SYNOPSIS... Seasonably dry weather in on tap today as weak high pressure builds into the region. Disturbances moving along a stalled frontal boundary south of the region will bring renewed chances of showers tonight through the day Wednesday, with best chances south of the Capital Region. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... As of 1020 PM EDT, regional radars remain quiet, and thus no precipitation is expected through at least midnight regionwide, if not until after 2 AM. Still some thin spots in the clouds persist across northern areas, where temps have already dipped into the lower/mid 50s in a few areas. Clouds are thicker across southern areas, where temps remain elevated, generally in the lower/mid 60s. A light south wind has also kept temps elevated within the Hudson River Valley from Albany south, with mid/upper 60s. As mid/upper level winds continue backing overnight, moisture across PA, along with showers across western PA and OH should continue expanding north and east. Latest RAP13 and HRRR suggest some showers may reach the I-84 corridor into NW CT after 08Z/Tue, so have backed off on PoPs in most southern areas, increasing to slight chance to low chance between 08Z-12Z/Tue. Better chances for showers, and northward expansion, is expected after 12Z/Tue. Have lowered temps slightly across northern areas where they have locally dipped into the lower 50s. Expect mins in the mid/upper 40s in some portions of the SW Adirondacks, with lower/mid 50s in many northern areas, and even some portions of the southern Greens and northern Berkshires overnight. Elsewhere, clouds and higher moisture levels should keep temps mainly in the upper 50s to lower 60s. Some patchy fog may form overnight, especially across some northern sheltered valley areas. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... Showers are expected to continue in southern areas through the morning and some isolated to scattered showers could build as far north as the Mohawk Valley and southern VT before everything exits during the afternoon. Outside of the showers there should be some thin spots and breaks in the cloud cover allowing temperatures to rise somewhat through the day. Highs Tuesday in the 70s with around 70 to lower 70s in higher terrain and southern areas where the best coverage of clouds and showers will be. There is a general consensus for a dry period Tuesday night into Wednesday morning but there are some uncertainties as to where the northern edge of the cloud cover and diffuse low level forcing and low level dew point gradient sets up. There could be some lingering isolated showers and persistent cloud cover over parts if not much of our region Tuesday night into Wednesday but again, there is really no well defined upper system and very weak and diffuse low level forcing. There could be some scattered showers and isolated thunderstorms Wednesday afternoon due to daytime heating and temperatures reaching convective temperatures in a slowly increasingly humid airmass. Highs Wednesday in the 70s to around 80. There is an increasing consensus that a well organized upper system that is currently in the SW U.S. will track across the central U.S. and affect our region Thursday into Thursday night. There is quite a spread in sources of guidance/ensembles as to the timing and whether part of the warm sector and enhanced instability can build north into our region. There are some signals that the eastern Catskills, mid Hudson Valley and NW CT could see some strong thunderstorms Thursday afternoon depending again, on how far north steeper midlevel lapse rates, low level jet energy and the gradient of the thermal/moisture boundary associated with the cold front. It is just worth keeping an eye on severe weather potential and localized heavy potential for Thursday afternoon and night. The strong thunderstorms could miss our region to the south as indicated in some sources of guidance. Indicating showers and thunderstorms increasing in coverage through Thursday afternoon. Highs in the 70s but around 70 higher terrain. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... Medium-range NWP is depicting an anomalously strong low pressure system tracking from the vicinity of PA to off the southern New England coast Thursday night ahead of a strong and progressive midlevel trough. Still some uncertainty with the track of this system, but current consensus puts us on the cold side of the low, such that deformation precip looks like a good possibility. Despite lingering uncertainty in storm track, likely to categorical PoPs are warranted. Left thunder out of the forecast assuming this southerly track. Height rises in the wake of this trough quickly build in, resulting in a drying trend Friday into Saturday. Temps may come up a little short of normal Friday with some cold advection and perhaps some lingering morning clouds and showers, but temps return closer to normal by Saturday. Will keep the forecast dry Sunday with temperatures continuing near normal, but entry level shower chances return for Monday as indications are the the midlevel flow goes more zonal, reducing the subsidence. There is uncertainty as to how fast this occurs, such that confidence in a completely dry weekend is not extraordinarily high at this point, but it looks more likely than not to be mainly dry. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... A frontal system will remain south of the TAF sites through Tuesday. A weak wave of low pressure will track along this front during Tuesday, bringing clouds and some showers, especially to southern TAF sites (KPOU and KPSF). Best chances for showers appear to be after 10Z/Tue, again focusing at KPOU and KPSF. Showers may linger until 16Z-18Z/Tue before tapering off. MVFR Cigs and VFR/MVFR Vsbys will be possible as any showers occur, with a smaller chance of intermittent IFR conditions within any moderate rain showers. After the showers end, MVFR Cigs are likely to persist at KPOU and KPSF. Some showers could reach as far north as KALB, especially between roughly 14Z-18Z/Tue. These could lead to some MVFR conditions, esp Cigs. Otherwise, mainly VFR conditions with Cigs 4000-6000 FT AGL. The showers and any sub-VFR conditions should remain south of KGFL through Tuesday. However, there is a small chance of patchy ground fog tonight, which could lead to a few dips into MVFR/IFR flight categories. This is a low probability, and have left out mention with current TAFs, but trends will need to be watched in case amendments are needed. Winds will remain light (under 5 KT) and variable in direction through Tuesday. Outlook... Tuesday Night: Low Operational Impact. NO SIG WX. Wednesday: Moderate Operational Impact. Scattered SHRA...TSRA. Wednesday Night: Low Operational Impact. Isolated SHRA...TSRA. Thursday: High Operational Impact. Chance of SHRA...TSRA. Thursday Night: High Operational Impact. Definite SHRA. Friday: Moderate Operational Impact. Chance of SHRA. Friday Night: No Operational Impact. NO SIG WX. Saturday: No Operational Impact. NO SIG WX. && .FIRE WEATHER... Seasonably dry weather in on tap today as weak high pressure builds into the region. Disturbances moving along a stalled frontal boundary south of the region will bring renewed chances of showers tonight through the day Wednesday, with best chances south of the Capital Region. RH values will exceed 45 percent through Wednesday with near 100 percent each night. Winds will be light and variable at less than 15 mph tonight and east southeast becoming south at less than 15 mph Tuesday through the day Wednesday. && .HYDROLOGY... No widespread hydrological issues are expected in the Albany Hydro Service Area into the mid week. Disturbances moving along a stalled frontal boundary south of the region will bring renewed chances of showers tonight through the day Wednesday, with best chances south of the Capital District. Another wave of low pressure may bring a widespread soaking rainfall Thursday into Friday, but the amount of rain is still uncertain. Within bank rises on the main stem rivers is likely. 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...NAS NEAR TERM...KL/NAS SHORT TERM...NAS LONG TERM...Thompson AVIATION...KL/Thompson FIRE WEATHER...NAS HYDROLOGY...NAS
Area Forecast Discussion
National Weather Service Amarillo TX
643 PM CDT Mon Jun 17 2019 .AVIATION... For the 00z TAFs... Scattered strong to severe thunderstorms currently over eastern plains of New Mexico expected to impact all of our terminals this evening. Storms currently moving northeast at around 15 kt. Expect thunderstorms to begin threatening DHT, GUY and AMA around 00z, 01z and 03z, respectively. Storms expected to cause variable surface winds briefly gusting above 35 kt with visibilities briefly falling into MVFR range. Expect that thunderstorms will have moved east of all terminals by 06z, although potential exists for redevelopment near AMA between 07z and 10z. Tuesday morning expected to be characterized by thinning clouds and light southwest surface winds. Chance of afternoon thunderstorms included at northern terminals on Tuesday. Apart from brief visibility reductions in thunderstorms, VFR conditions expected next 24 hours. Cockrell && .PREV DISCUSSION... /Issued 302 PM CDT Mon Jun 17 2019/ SHORT TERM...This Afternoon and Tonight... Thunderstorms are currently forming in southeastern CO along a surface trough that extends south into New Mexico. Additional development is occurring in the higher terrain of NM near a eastward advancing shortwave, with more recent convective initiation along the surface trough near KTTC. The shortwave is expected to continue moving into the area with enhanced PVA by 00z in advance of the parent trough over southern CA. An axis of better moisture is expected around the TX/NM border near the surface trough where 850mb to 700mb theta-E advection is maximized through the afternoon. Surface dew points were in the mid to upper 50s just east of the surface trough with 10 to 20 knot south to southeasterly winds. Even though 700mb theta-E advection is expected to shift east through the evening, the surface to 850mb moisture drops off from the central Panhandles into the eastern Panhandles. This results in the instability axis of around 1500 MLCAPE that extends from the far western Panhandles Counties into northeastern NM. Veering wind profiles do support effective shear of 25 to 30 knots, which will be the main limiting factor for higher levels of convective organization. That being said, the moderate instability and steep lapse rates along with the directional shear will support strong updrafts which may take on supercell characteristic at times as storms move into out western zones through early evening. These storms will be high-based given LCL around 2000 m. As the shortwave dynamics arrive around 00z, additional storms are expected to develop with more of a linear mode into the evening. However, as storms move eastward at around 15 to 20 mph, they will run into more stable airmass, with perhaps only a few hundred J/kg MUCAPE available in the eastern half of the Panhandles. Given stout shortwave and 700mb moisture advection, storms will persist but weaken below severe levels given weak updrafts. As storms first move into the more stable air, will have to watch for strong downdrafts given modest DCAPE and decaying updrafts. Can`t rule out a few heat burst or even some attempt at a wake low developing into the night. Finally, enough remnant moisture and elevated lift persist across the western zones so that some re-development is possible after 03z. This has been a consistent trend in the HRRR mainly favoring the southwestern Texas Panhandle through about 09z. These storms could become strong given decent MUCAPE. Ward LONG TERM... On Tuesday a dryline should sharpen up across the western Panhandles and a cold front should be pushing into the Oklahoma Panhandle by the afternoon. Forcing may not be strong enough to get thunderstorms going just by these two features alone as cap will be fairly strong. However, there is an upper level short wave trough that will move toward the northern Panhandles, that may provide enough lift to remove the lid enough to get thunderstorms going. If thunderstorms develop, then they will probably become severe with large hail and damaging winds the main threats. Thunderstorms may move into the northwestern CWA on Wednesday afternoon from the mountains of New Mexico and Colorado if a short wave trough can keep the storms going. The forecast turns dry for Thursday and Friday and temperatures soar above normal. Thunderstorms will then again be possible for the weekend as a cold front moves through the area. && .PRELIMINARY POINT TEMPS/POPS... Amarillo TX 60 86 60 87 61 / 40 30 10 10 10 Beaver OK 61 86 58 84 61 / 40 40 40 10 5 Boise City OK 57 84 53 81 56 / 60 40 10 20 5 Borger TX 62 87 61 88 62 / 40 30 20 20 5 Boys Ranch TX 58 88 58 88 60 / 50 20 10 20 10 Canyon TX 60 87 59 90 61 / 50 20 10 10 10 Clarendon TX 63 87 63 88 62 / 20 30 20 10 5 Dalhart TX 57 87 55 83 56 / 60 30 10 20 5 Guymon OK 59 85 56 83 59 / 50 40 20 20 5 Hereford TX 59 88 60 92 61 / 60 10 5 5 10 Lipscomb TX 63 86 61 86 62 / 30 50 30 10 5 Pampa TX 61 83 61 86 61 / 30 40 20 20 5 Shamrock TX 64 87 64 88 63 / 20 40 30 10 10 Wellington TX 66 89 66 91 64 / 20 30 30 10 10 && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$ 03/77
Area Forecast Discussion
National Weather Service La Crosse WI
1047 PM CDT Mon Jun 17 2019 .SHORT TERM...(Tonight through Tuesday Night) Issued at 241 PM CDT Mon Jun 17 2019 At 1830Z, a weakly convergent surface boundary was present from Red Wing MN to just north of Austin MN and southwestward into western IA. SBCAPES are around 1000 J/Kg along the boundary in sern MN with showers developing. Further south into IA, thunderstorms were ongoing near the SBCAPE max of 2000 J/Kg. The moisture is quite shallow with MLCAPES dropping to 500 J/Kg in sern MN. Thus, more mixing this afternoon could lower the ambient CAPE for TSRA potential. This boundary remains nearly stationary through the evening awaiting a better push from the northwest, which will come overnight as a stronger shortwave trough rotates south out of Canada. Right now, heights are building over the region. Thus, diurnal storms are expected for several hours west of Highway 52. Wind shear and CAPE are transposed north and south and not aligning for higher severe weather threat. But, the boundary could provide a storm anchor and also a landspout environment to pull heavy local rainfall and funnels into the possible outcomes through very early evening. Storms will decrease rapidly in coverage this early evening as any remaining CAPE wanes, and as the front beings to move south, some late night moisture transport and convergence in the low levels will provide another spark to a minimal MUCAPE pool for showers and thunderstorms early Tuesday south of I-90. Have trended rain chances higher for this time frame. Frontal boundary will remain across southern WI into northeast IA Tuesday afternoon for additional shower/thunderstorm development. Will keep and eye on this for the possibility of localized heavier rain amounts given precipitable water values hovering around 1.5" and potential for training of the showers/storms. Frontal boundary lingers across southern WI into northeast IA through Tuesday night but loss of daytime heating with sunset will diminish shower/storm chances. .LONG TERM...(Wednesday through Monday) Issued at 241 PM CDT Mon Jun 17 2019 High pressure drives the aforementioned Tuesday night frontal boundary further south Wednesday into IL/central IA while a fairly organized area of low pressure lifts east/northeast out of the Central Plains. Some lingering mid-level f-gen hangs on across southern WI into northeast IA for a chance of scattered showers and isolated storms. Otherwise, northeast surface flow will keep temperatures in check in the lower/middle 70s. Stronger ridge of high pressure moves over the area Wednesday night into Thursday for a brief period of quiet/drier weather. Look for lows Wednesday night in the upper 40s to the middle 50s and highs Thursday in the 70s. Warm air advection and moisture transport ahead of low pressure moving in across the Plains sets up the stage for more showers and thunderstorms Thursday night through Saturday. Will have to keep a close eye on the possibility of some stronger/severe storms Saturday as GFS shows MUCAPE south of I-90 increasing into the 3500-5000J/Kg range along with bulks shear around 35kt. In addition, could see some localized heavy rainfall with these storms. Surface low pressure progresses northeastward through the area Saturday night into Sunday, taking the bulk of showers and storms with it. Passage of mid-level trough keeps shower/thunderstorm chances going on Monday. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1047 PM CDT Mon Jun 17 2019 The showers that were moving across the area have all but dissipated, leaving behind mid-level clouds for a VFR ceiling. Still anticipating that there will be a increase in the low level moisture transport into the front over northern Iowa overnight that should help generate some more showers. The last few runs of the HRRR have been showing less development than earlier runs and farther south. Based on this trend, have removed the VCSH mention overnight along with any MVFR ceilings. Some concern for fog development overnight, but unsure how much will form underneath the clouds. For now, will not include any fog and stay with VFR conditions through Tuesday evening. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION...04
Area Forecast Discussion
National Weather Service Cleveland OH
1028 PM EDT Mon Jun 17 2019 .SYNOPSIS... A weak stationary front over the area will begin to lift back north as a warm front this evening as a wave of low pressure moves northeast along the front. The low will move east of the area late tonight forcing the front back south as a cold front Tuesday. Another low pressure system will move northeast along the front Wednesday and yet another low will move east across the area Thursday. && .NEAR TERM /THROUGH TUESDAY NIGHT/... Minor adjustments to pops, temps and QPF with the evening update. Main area of precip associated with weak low pressure moving northeast into the southern part of the area, although rainfall amounts with this activity are light. The more moderate/heavy rainfall associated with stronger convection will remain south of the area over the next several hours. The main question is how much redevelopment will occur overnight across the area along and just north of the surface boundary on the nose of a strengthening low level jet. The latest runs of the HRRR are bullish on redevelopment shortly after Midnight across the area, and the runs have been progressively moving the development northward. Have expanded pops slightly northward as well as rainfall amounts, but have lowered the overall totals just slightly for the southern part of the area. There is still a decent shot at upwards of an inch of rain in isolated locations overnight, but widespread amounts less than an inch will be more common. Will leave all headlines in tact given the potential for additional moderate rainfall amounts. Original discussion... Yet another shortwave trough will move east across the area tonight and will be responsible for pushing a weak low pressure system northeast into the region. Showers and thunderstorms continue to break out across southern Illinois and Indiana at this time. This activity is progged to move northeast across the southern half of the local forecast area tonight. Moist air mass will continue to be responsible for periods of moderate to heavy rain across the south where significant rainfall already occurred last night. A band of showers continues to move across this same area at this time and the combination of the two rainfall events will only compromise the area with more flooding issues. Rainfall totals up to 1.5 inch additional is expected across the flash flood watch area overnight. Due to the potential for locally heavy rain at times in the watch area, locally higher rainfall amounts are possible. Further north closer to the lake, the rainfall threat will taper off from south to north. Patchy dense fog is also possible overnight again, especially areas where showers have developed this afternoon and from the recent rain last night further north. Low pressure pulls out to the northeast Tuesday and tries to pull the stationary front slightly south. Still thinking that some lingering showers are possible along the front Tuesday. The threat diminishes as the night progresses Tuesday night but next low pressure system will send the warm front back north toward the area with another round of moisture by morning. Temperatures across the area will be in the upper 50s near the lake and middle 60s across the south tonight. Warmer air will lift north into the region Tuesday into the middle 70s followed by similar lows for Tuesday night. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... Active pattern with additional rainfall continues in the short term. The daytime hours on Wednesday expected to me mostly dry and a little warmer before active weather returns Wednesday night. Low pressure will develop ahead of a shortwave west of the area on Wednesday. Moisture surges back north on Wednesday night with showers and scattered thunderstorms expanding and PW values reaching 1.80 inches. Models continue to show some timing differences with the NAM/Reg GEM showing the surface low overhead by 12Z Thursday while the ECMWF/GFS are a little slower. Timing will play a role in if daytime heating will be a factor for more robust convection on Thursday afternoon. At this time rain looks like the greatest concern with most of the area receiving an additional 0.75 to 1.5 inches of rain. Given the strength of the low, can not rule out a few stronger thunderstorms as well, especially along the warm front so that will be something to monitor. Instability may be a limiting factor given the amount of clouds and rain. Rain will depart to the east on Thursday night, with high pressure expanding on Friday. Temperatures will drop back into the lower to mid 70s on Thursday and Friday. && .LONG TERM /FRIDAY THROUGH MONDAY/... Wet weather will persist through this period. Dry conditions are expected Friday night as high pressure builds across and east of the area by Saturday morning. A warm front will move across the area on Saturday and produce another round of showers and thunderstorms which will continue into Saturday night. The region will be in the warm sector on Sunday with a continuing chance for storms. Models diverge Sunday and Monday on the approach and passage of a cold front that is expected to cross the region. More showers and thunderstorms can be expected. && .AVIATION /00Z Tuesday THROUGH Saturday/... A frontal boundary will remain stationary just south of the terminals overnight through Tuesday. IFR conditions are expected near the front and near the lake at KERI and possible KCLE, with conditions primarily in the MVFR range at KTOL/KFDY. Showers will impact mainly KMFD, KCAK and KYNG, and have backed off on thunder chances slightly given the latest observational and guidance trends. Winds will be light and variable near the front, but generally out of the north through the period north of the boundary. OUTLOOK...Non-VFR possible through Friday. && .MARINE... Generally light wind conditions will continue on Lake Erie through Wednesday as a frontal boundary remains south of the lake. East to northeast winds will increase late Wednesday night into Thursday ahead of a low pressure system approaching from the west. Winds of at least 5 to 15 knots can be expected but could be stronger depending on the track and strength of the low. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Flash Flood Watch until 4 AM EDT Tuesday for OHZ017-020>023- 027>033-036>038-047. PA...None. MARINE...None. && $$ SYNOPSIS...Lombardy NEAR TERM...Greenawalt/Lombardy SHORT TERM...KEC LONG TERM...LaPlante AVIATION...Greenawalt MARINE...KEC
Area Forecast Discussion
National Weather Service State College PA
1137 PM EDT Mon Jun 17 2019 .SYNOPSIS... An unsettled and stormy weather pattern is expected across central Pennsylvania this week thanks to the close proximity of a slowly meandering stationary front over Pennsylvania. There will be multiple rounds of heavy downpours with the potential for flooding and isolated severe storms. After a cool day today, temperatures will get back closer to normal highs for the rest of the week, but remain milder than normal at night. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... Active night coming up with convection to the west headed towards central PA. HRRR very consistent with some locally heavy rain with these storms in predawn hours. One hour FFG is generally 1.5-2" across the area, PWAT is running 1-2 STDs above normal for June, and dewpoint 65-70F over the srn third+ of the CWA. With multiple rounds of showers/storms expected, and the high moisture of the atmosphere right now, will continue with FFW even though nothing is immediately expected. Min temps will vary from the upper 50s across the north, to upper 60s in the south. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... The threat of flash flooding continues Tuesday into Tuesday night, despite the possibility of a few to several hour lull in storms late Tuesday morning and early Tuesday afternoon. The Flash Flood Watch runs into Tue night as additional storms will ride along on the train later Tues afternoon/evening. The ground will only be getting wetter, and streams swelling. Temps may warm a little for the daytime on Tues, but that all depends on the timing of the minor troughs aloft and how long we can spend in between the rounds of rain/storms. Have kept the forecast high in continuity, but could see things being a little cooler on Tuesday if the storms don`t exit stage right in the morning, and we get some breaks of sun. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... Wet pattern with repeat rounds of rain along nearly stationary frontal zone will continue to bring an increased flood risk to south central PA through midweek. A strong low pressure system for June will track across the area on Thursday, and could bring a significant threat of severe storms and flash flooding. Breezy and drier conditions will arrive into Friday as the system continues to deepen as it moves away from the area. The latest guidance favors a dry start to the weekend before more showers and storms return to the forecast on Sunday. Persistent cloud cover suggests highs running a bit below average through midweek while higher dewpoints favor muggy nights/above avg lows. Near normal temps are forecast through the weekend. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... Abundant low level moisture and light wind in vicinity of a stalled frontal boundary will lead to developing low cigs and fog across central Pa overnight, along with the chance of showers. Latest SREF probability charts indicate IFR conditions will become likely late tonight over the high terrain of the Alleghenies from KBFD south through KJST. Further east, thickening cloud cover could limit the extent of fog formation, but can`t rule out patchy IFR vsbys. Diurnal heating and resulting mixing of drier air aloft will yield improving cigs/vsbys Tuesday, with predominantly VFR conditions by mid to late afternoon. However, a brief reduction will remain possible from scattered showers/thunderstorms. .Outlook... Wed...AM rain/low cigs possible. Scattered PM tsra impacts possible. Thu...AM rain/low cigs possible. Scattered PM tsra impacts possible. Fri...AM low cigs possible W Mtns. Sat...No sig wx expected. && .CLIMATE... Astronomical summer (solstice) begins Friday, June 21st at 1154AM EDT (1554 UTC). && .CTP WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through late Tuesday night for PAZ017>019- 024>028-033>036-049-050-052-056>059-063>066. && $$ SYNOPSIS...Lambert NEAR TERM...Ross/Lambert SHORT TERM...Lambert/Evanego LONG TERM...Steinbugl AVIATION...Fitzgerald CLIMATE...
Area Forecast Discussion
National Weather Service Hastings NE
710 PM CDT Mon Jun 17 2019 ...AVIATION UPDATE... .SHORT TERM...(This evening through Tuesday) Issued at 346 PM CDT Mon Jun 17 2019 Aloft: High-latitude blocking was over the N Atlc with a large low over Hudson Bay. S of this low...the flow was generally weak over the CONUS...espcly the S half. There are too many features to mention...but of concern to our CWA is the large but weak trof over the Wrn USA. A weak shrtwv trof is lifting NE acrs AZ/NM. This trof will cont NE tonight and mv into NEB/KS tomorrow. Probably of greater concern is the RRQ of a 90 kt upr-lvl jet from SD into the NE USA. By 12Z/Tue...a mid-lvl (700 mb) low is fcst to form and slowly mv E acrs Srn NEB. Surface: Occluded/wk low pres was over Nrn MN with a cool front extending SW acrs the Sandhills. As this low heads into the GtLks tonight...the front will sag into the CWA tonight and become stationary along the NEB-KS border tomorrow. Meanwhile...weak low pres will form along the front (under the mid-lvl low) approximately from IML-MCK-HJH from 12Z-00Z. Rest of this aftn: Partly-mostly cldy. Isold shwrs...and possibly some tstms with the best chance N of I-80 per the last few HRRR runs. There is not a clr signal on tstm potential. The 12Z HREF shows that the HRRR is by itself. None of the other CAMs initiate anything significant. SPC mesoanalysis has about 1000 J/kg with no more than 20 kts of 0-6 km shr. We`ll downplay threat of svr tstms in the HWO. Tonight: Partly-mostly cldy. Sct tstms will occur N and W of the CWA...along the cool front to the N and over the high plns to the W. This has already begun. Some of these storms could congeal into a complex that mvs into the CWA after midnight. Fcst soundings suggest this situation is ideal for hvy rain with skinny CAPE...low CAPE totals...slow movement and potential for warm rain processes. Tue: The rain that mvs in tonight will cont to progress E acrs the CWA during the mrng and probably expand thru the day as the RRQ of the upr jet provides persistent deep lift to supplement lift associated with low-lvl FGEN. This should result in repeated development of slow-moving shwrs with embedded tstms. While PWAT values will not be excessive...they will be abv normal (1.6"). Cont`d low/skinny CAPE and slow mvmt of the low/rain should result in some healthy if not excessive rainfall totals. QPF: The mdl blends and WPC suggest a widespread 1-2" tngt thru Tue evng. However...some CAMs suggest localized spots could see 3-5". Soil mstr is still at the 99th percentile. If 3-5" occurs over a fairly large area...expect flooding will develop in low-lying areas...creeks and psbly larger rivers. Because of this...hv issued a Flood Watch from midngt tonight thru Tue evng. The rain may end by that time...but if flooding materializes...the flooding could last beyond that. Contemplated adding some N-cntrl KS counties to the watch gvn the 09Z/SREF probs for at least 3" extend down there. This may need to be done by the next shift. There is a chance a few svr tstms could occur in the aftn/evng... primarily over N-cntrl KS...but it`s conditional on if sufficient instability can dvlp. Shear will be marginal...maybe as much as 25 kt. .LONG TERM...(Tuesday night through Monday) Issued at 346 PM CDT Mon Jun 17 2019 Aloft: The low that has been blocked over the Aleutians will move downstream into the Nrn Rckys this wk...carving out a longwave trof over the Wrn USA. As a result...persistent WNW flow here on the Cntrl Plns will become SW Thu-Sun. Surface: As the upr low mvs into the Nrn Rckys...a warm front will form and cross the CWA Wed night as a deep sfc low evolves over AB. The cool front associated with this low is then fcst to mv thru Fri. Temps: Cont`d much cooler than normal Wed. Near normal Thu-Fri. Then probably cooler than normal Sat-Mon. Rain: Nothing of significance until Thu night into Fri AM when the mdls are suggesting an MCS could dvlp and cross part of the CWA. Sct tstms could also fire Fri aftn along the cool front. SPC already has the CWA outlooked for a risk of svr tstms. This seems very reasonable given that rich dwpts in the 60s to low 70s are fcst to advect N underneath a plume of steep mid-lvl LR`s. Shr/instability should be more than sufficient for svr tstms as long as the timing/location of the front holds. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Tuesday) Issued at 710 PM CDT Mon Jun 17 2019 Starting out the period as VFR but conditions are expected to deteriorate down to IFR overnight and through the day tomorrow and could flirt the line of LIFR at times. There is already plenty of storm activity off to the west along the NE-CO border. These storms are associated with the cool front that will be moving through the area this evening, and bringing the active environment with it. Showers and thunderstorms are likely for most of tonight and tomorrow. Ceilings are expected to lower gradually to around IFR overnight with the accompanying frontal system and storms. Visibility could be impacted at times in heavier storms. Visibility is expected to drop to between 4-6 SM during the morning hours, and then could briefly drop further to 2-3 SM in the early afternoon tomorrow, before ceilings begin to lift. Winds are expected to become light and variable for a little while this evening ahead of the approaching front. After the passage of the front winds will be from the NE and will pick up to around 5-10kts. && .GID WATCHES/WARNINGS/ADVISORIES... NE...Flood Watch from midnight CDT tonight through Tuesday evening for NEZ039>041-046>049-060>064-072>077-082>087. KS...None. && $$ SHORT TERM...Kelley LONG TERM...Kelley AVIATION...Shawkey
Area Forecast Discussion
National Weather Service Wilmington NC
1053 PM EDT Mon Jun 17 2019 .SYNOPSIS... Warm and humid weather conditions continue across the Carolinas this week as high pressure shifts well offshore. A chance of showers and thunderstorms will persist each day this week until the next cold front moves through late in the week. && .UPDATE / 1050 PM /... Quiet conditions tonight with lows in the low to mid 70s on track. No major changes to the forecast. && .NEAR TERM /THROUGH TUESDAY NIGHT/... As of 3 PM Monday...Scattered convection has developed along the differential heating boundary setup by the coastal plains and sandhills. Also, isolated convection had formed along the sea-breeze boundary south of Murrells Inlet. HRRR is a bit slow on the development and it continues to show the coverage remaining west of I-95 with only isolated convection elsewhere west of the sea breeze and dying after sunset. The depth of the moisture over the region is on the increase and will be closer to 2" by Tuesday afternoon. Still not much forcing in the upper levels but as we saw on Sunday any large scale lift that is undetected will help diurnal convection on Tuesday. The nam model CAPE values show 2500+ J/kg in the heat of the day Tuesday. So with the little synoptic scale force will go with a 30% PoP in the western areas along the sandhills/coastal plains differential heating boundary and a 20 percent chance along the sea-breeze, Lows tonight and Tuesday night are expected to range between the lower 70s inland to middle 70s at the coast. Highs on Tuesday should reach the 90 to 93 degree range and will be in the mid 80s at the beaches. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... As of 330 PM Monday...Better chances for rain Wednesday (50% PoPs) than Tuesday, as shortwave energy embedded in the W/SW flow aloft moves through the area in conjunction with ~75% 1000-500 mb RH. Convection again should be diurnal in nature, but still could see some shras/tstms early in the day as well depending on the timing of the shortwaves. High temps in the upr 80s to lwr 90s. Wednesday night will bring a break in the pieces of shortwave energy moving overhead and thus only have 20-30% PoPs. Low temps mainly in the mid 70s. && .LONG TERM /THURSDAY THROUGH MONDAY/... As of 330 PM Monday...Models have come into better agreement on the timing of a cold fropa early in the period. The front will cross the area late Thursday bringing another good chance of rain, followed by drier conditions Friday into the weekend with weak high pressure in the vicinity. Precip Chances: 40-60% chance of shras/tstms Thursday into Thursday night, decreasing to 20% Friday morning. Dry Friday afternoon through Saturday, with low diurnal rain chances returning Sunday. Temps: Near to slightly above normal through the entire period...highs avg in the upr 80s to mid 90s, with lows in the low/mid 70s. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... As of 00Z...VFR throughout the period with clear skies. Stratus is possible Tuesday morning, but over the last few model runs, continues to look less likely. Calm winds overnight will become southerly during the day tomorrow as high pressure builds in from the west. More moisture during the day on Tuesday as compared to today will provide a good opportunity for scattered thunderstorm across the area. Extended Outlook...Mainly VFR with brief MVFR/IFR conditions Wednesday thru Friday from convection and early morning fog and/or low stratus. && .MARINE... As of 330 PM Monday...High pressure well off the southeast coast will continue to slowly shift off the coast. A trough of low pressure will move toward the coast late Tuesday. This will cause the southwest winds of 5 to 10 knots to increase from the south to 15 knots. The seas will begin around 2 feet tonight and will increase to 3 to 4 feet farther off the coast Tuesday night. A southeast swell of 1.5 feet from the southeast is expected to continue through the near term. A piedmont trough develops Wednesday and increases the gradient over the waters to the tune of about 15 kt. Seas should build to 4 to 5 ft by Wednesday night. A further deterioration in wind/seas slated for Thursday. Upper-level energy impinges from the west but low-level wind fields strengthen ahead of a weak cold front. A Small Craft Advisory could be needed Thursday/Thursday night. A turn to west and diminishing winds and seas then expected for Friday and Saturday. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...None. && $$ SYNOPSIS...MAS NEAR TERM...RH SHORT TERM...MAS LONG TERM...MAS AVIATION...21 MARINE...MAS/RH
Area Forecast Discussion
National Weather Service Lincoln IL
913 PM CDT Mon Jun 17 2019 .UPDATE... Issued at 913 PM CDT Mon Jun 17 2019 Some light rain lingers across east central Illinois this evening, but low clouds prevail over most of the CWA. Main question will be with additional shower/storm development. Seriously considered dropping the Flash Flood Watch near and south of I-70, but decided to leave it in place as the HRRR brings some heavier showers into the area toward 3-4 am. Current activity is generally along the Ohio River and shouldn`t impact us, but the new development appears to be focused just north of the frontal boundary, which should be in the general vicinity of I-64 overnight. Temperatures are generally on track, but some updates for the precipitation trends have recently been sent. && .SHORT TERM...(This evening through Tuesday) ISSUED AT 332 PM CDT Mon Jun 17 2019 This afternoon, upper low is slowly lifting across the Ozarks towards the local area. At the surface, a stationary front is draped from just south of St Louis ENE along and just south of the I-70 corridor. Dew points are pooling in the upper 60s to around 70F near the front, while temperatures have warmed to around 80F in the warm sector. North of the front, low stratus has prevailed through the day and held temperatures in the 60s to lower 70s. Thunderstorms are ongoing along the I-70 corridor this afternoon in response to the shortwave trough that ejected northeast from the main upper low. These storms have been slow moving in the presence of weak low and mid level flow, and what movement there has been is often training over areas already impacted. Anticipate a corridor or 1 to 2 inches of rain through late this evening, with locally higher amounts across areas that have already been well saturated by recent heavy rain events. While the intensity of the rain hasn`t been too bad so far today, the other aforementioned factors continue to support a flash flood watch through at least late this evening if not overnight. This wave should exit east of the CWA by around sunset this evening, which coupled with the loss of daytime heating, should allow precip to wane in coverage. Cannot rule out at least some isolated to widely scattered convection to continue overnight as the main upper low begins to accelerate eastward, and the focus will remain in the far southeast counties of the forecast area. Overnight, temperatures remain relatively mild under the presence of cloud cover and high dew points. Clouds should lower again overnight and cannot rule out some patchy fog redeveloping after midnight. On Tuesday, don`t expect much in the way of synoptic scale forcing over the region and most of the forecast area will remain dry. Flow aloft becomes zonal in the wake of the damping upper low. The surface boundary likely persists over the region, however, and will serve as the main focus for diurnal convection again across the far southeastern CWA. Guidance suggests modest instability with MLCAPE to around 1000 J/kg will develop within the warm sector Tuesday afternoon. Deep layer shear will be weak in the continued weak mid level flow, so the likelihood of any severe storms is fairly low. .LONG TERM...(Tuesday night through Monday) ISSUED AT 332 PM CDT Mon Jun 17 2019 There has been a good signal for several days now that a shortwave trough will track across the mid Mississippi Valley on Wednesday. This wave will intersect moisture rich and unstable air in place over Illinois on Wednesday resulting in additional chances for showers and thunderstorms across the forecast area. Some of these storms could produce heavy rain and will again have to closely monitor flooding potential during this time frame. Yet another wave is progged to dig across the Pacific Northwest Thursday and carving out a deep across the Great Basin over the weekend. As this occurs, anticipate downstream amplification of the longwave ridge over the mid section of the country as very warm (20C+) 850mb temps spread into the Midwest by this weekend. Thursday and most of Friday should be dry as a result of the building upper ridge over the region, and a warming trend will kick off in earnest Friday. Saturday in particular could be hot over the area, but there remains some uncertainty in how hot given thunderstorm chances returning along with associated cloud cover. Near 90F or possibly into the 90s not out of the question depending on how things come together. Thermal ridge should persist over the area on Sunday before the upper ridge begins to break down and shift east early next week. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 700 PM CDT Mon Jun 17 2019 Ceilings are the main concern through Tuesday morning, as light winds and a low level inversion keep any significantly clearing at bay. Ceilings around 1500 feet generally found across central Illinois at 00Z, and these should largely stay in place. Have included a period of IFR conditions at KSPI/KPIA, with ceilings just to the south already getting down to that level. Skies expected to begin scattering out toward midday Tuesday. && .ILX WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch until 7 AM CDT Tuesday for ILZ062-063-066>068- 071>073. && $$ UPDATE...Geelhart SHORT TERM...Deubelbeiss LONG TERM...Deubelbeiss AVIATION...Geelhart
Area Forecast Discussion
National Weather Service Louisville KY
955 PM EDT Mon Jun 17 2019 .Forecast Update... Issued at 955 PM EDT Mon Jun 17 2019 Scattered convection remains in progress across the western half of the forecast area this evening. Two clusters of convection will affect the region overnight. The first will be one area of convection lifting northward out of Tennessee. This will bring more widespread showers and thunderstorms to portions of south-central KY, mainly the Lake Cumberland region. Overall severe threat with this activity remains low due to the loss of heating and marginal instability. However, PWATs of 1.5-1.8 inches will allow for efficient, low-centroid convection that can produce heavy and efficient rainfall. Given that this area has been drier in the last few days, FFG guidance in this part of KY remains rather high and isolated minor flooding issues can be expected. A second area of convection looks to be developing along a line from Beaver Dam (Ohio county) northeastward through Metro Louisville and then northeast to the southern suburbs of Cincinnati. This activity looks to be focused along a remnant outflow boundary. Mesoscale analysis shows about 35-40kts of bulk shear here, which may be being enhanced by the nocturnal low-level jet. Recent HRRR runs suggests that this line of convection should continue to develop while lifting slowly northward overnight. Recent radar trends do show this line drifting northward and current thinking is that an axis of heavy rainfall will likely fall along the main stem of the Ohio River over the next several hours. PWATs in this area are around 1.6 to 1.9 inches, so efficient low centroid convection with heavy rainfall is likely to be the main threat here. Hourly FFG guidance in the metro is around 1.2 inches but increases to over 2 inches by the time you get into central Breckinridge/Hardin/Nelson counties. It drops off considerably to the north across southern IN with around an inch or so. Values out in the Bluegrass region are also low with 1-1.25 in/hr guidance. Areal placement of the Flash flood watch still looks good as the watch is placed well within the FFG guidance. Will need to watch portions of the Lake Cumberland region overnight as this area could pick up more rain which could require a southward expansion of the watch given the forecast of more rain over the coming days. Issued at 723 PM EDT Mon Jun 17 2019 Scattered convection continues across the region this evening. We`re starting to see some convection fire along outflow boundaries across southern IN. A corridor of convection from Dubois county eastward through portions of Crawford, Floyd, Harrison, and Clark looks likely over the next few hours. Strongest storms are pushing northeast out of Trimble county and may catch a portion of Henry county. Another area of convection is trying to develop down in the Rough River area of southern Breckinridge. Fine line outflow boundary evident in KLVX imagery in that vicinity. Cu field on GOES 16 is a little agitated, though MLCAPE are only around 900-1300 J/Kg here and have been decreasing over the last hour or so. Nonetheless, with PWATs over 1.5 inches, heavy rainfall can be expected with this activity. Mesoanalysis generally shows best instability down across south- central KY from Bowling Green eastward into the Lake Cumberland area. Tongue of higher DCAPE values exists from the TN Plateau region northeastward into the Lake Cumberland region. Strong convection over Middle TN will likely continue northeastward into our southeast sections this evening. Overall threat of severe weather is still marginal given the poor lapse rates and tall/skinny CAPE model proximity sounding profiles. Gusty winds and heavy rainfall look to be the primary threats. FFG values across the SE are much much higher than up across the northern half of the state, so flooding issues will likely be isolated and limited to areas that see training storms, which could occur in isolated corridors. && .Short Term...(This evening through Tuesday) Issued at 254 PM EDT Mon Jun 17 2019 Clouds from this morning`s rain have partially broken up and have allowed some destabilization of the atmosphere, with SBCAPE of 2k-3k J/kg. Cu has some more vertical development today than it did yesterday at this time, and a few thunderstorms have already begun to pop. Expect scattered thunderstorms to continue to develop this afternoon and continue into this evening. While locally gusty winds and small hail will be possible with the strongest storms, heavy rain will be the main threat in 1.8" PWAT air and plenty of moisture showing up on the soundings. One hour flash flood guidance is below an inch in some spots over southern Indiana and north central Kentucky. Scattered storms will decrease in coverage late this evening, with a lull in activity before showers and storms ramp back up in the pre- dawn hours and into Tuesday morning as a vort max moves up from the Tennessee Valley and brings another threat of locally heavy rain. Instability tomorrow afternoon should be hampered by the morning rain, but some scattered development should be possible with a broad east-west surface front still lined up roughly along the Ohio River and a weakening upper disturbance moving through. .Long Term...(Tuesday night through Monday) Issued at 345 PM EDT Mon Jun 17 2019 The long term portion of the forecast should start off relatively quiet Tuesday night. Flow aloft looks benign with the next wave still out over the Plains. Can`t totally rule out isolated showers given the very humid airmass, particularly east of I-65. Lows in the upper 60s will be common. The weather turns more active once again Wednesday afternoon through Thursday. A convectively-enhanced shortwave is forecast to swing through Wednesday night with the upper trough moving through on Thursday. Low pressure is forecast to deepen to the northeast over the Lower Ohio Valley Wednesday night, with a nice surge in the SW LLJ (35-40 kts). The proximity of the sfc low will provide a nicely veered wind profile, and the mid-level wave will bring a speed max of 50-60 kts. Instability is more marginal, but the moisture-rich environment will at least support strong storms capable of torrential rainfall, gusty winds, and lightning. A damaging wind threat could certainly develop as early as Wed afternoon and evening. The primary hazard may be flash flooding, especially with any training convection. The moisture transport surge in the warm sector will push PWATs into the 1.7-1.9 inch range, so rainfall production will certainly be efficient. The cold front sweeps through, bringing drying conditions Thursday evening. A dry period will likely continue through Friday and possibly Friday night. Friday morning lows will dip into the low to mid 60s. Friday looks like a rare nice weather day with highs in the 80s. The pattern is more amplified through the weekend, and ensemble means agree on a 594 mid level ridge developing over the Gulf of Mexico. At some point this weekend, convection in the Plains and Midwest will likely spill eastward into our region. And the hot, humid airmass may support at least scattered convection each day this weekend into early next week. && .Aviation...(00Z TAF Issuance) Updated at 713 PM EDT Mon Jun 17 2019 Scattered convection will be seen across the region this evening as an upper level disturbance moves through the region. Outside of storms, VFR conditions are expected through the evening hours. We plan on keeping some VCSH/VCTS in the TAFs through 18/03Z or so. Storms will be capable of brief heavy downpours, gusty winds, and perhaps some small hail. High resolution guidance suggests that we`ll see another surge of convection later on tonight, likely after 18/07Z or so. That convection will likely linger into the the morning hours on Tuesday and may result in cigs running near fuel-alternate thresholds. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...Flash Flood Watch through Tuesday afternoon for INZ076>079-083- 084-089>092. KY...Flash Flood Watch through Tuesday afternoon for KYZ025-029>043- 047>049-055>057. && $$ Update.......MJ Short Term...13 Long Term....EBW Aviation.....MJ
Area Forecast Discussion
National Weather Service Melbourne FL
1003 PM EDT Mon Jun 17 2019 .UPDATE... Current-Tonight...Debris showers across the interior earlier this evening have since dissipated, leaving a swath of low to mid level cloudiness over the area. Last several HRRR runs have favored shower/storm redevelopment overnight across the interior, but most recent has tapered back on activity. Although 00Z XMR sounding shows deep moisture pool, (PWAT of 1.94"), have restricted overnight PoPs for land to the Treasure Coast/Lake O region toward daybreak, as ambient conditions don`t appear to support redevelopment. Streaming showers and thunderstorms over the Gulf Stream waters will persist tonight, with likely PoPs through sunrise. Southwest flow returns as weak trough axis makes its approach to north FL, slightly tightening the pressure gradient and sending a weak wind surge over the Gulf Stream waters. Near normal overnight lows in the low 70s. && .AVIATION... Earlier convection and debris SHRA has since dissipated, leaving low to mid level cloudiness across most terminals which will gradually thin thru daybreak. Models suggest SHRA/TSRA northward push from KSUA/KVRB near 12Z, however confidence too low to include in current TAF. SW flow returns overnight, leading to sea breeze push to the eastern peninsula after 18Z tomorrow. Generally VFR. && .MARINE... Tonight...(modified prev) Tightening of the surface pressure gradient overnight will continue the Exercise Caution headlines for the offshore waters with southerly winds up to 15-20 knots and seas building to 4-5 ft well offshore. Closer to shore seas up to 3 ft. Higher shower/storm coverage is expected across the Treasure Coast waters and offshore waters overnight. Tuesday...SSW/SW winds to 10-15 knots and around 15 knots offshore with seas 2-3 ft near the immediate coast and up to around 4 ft well offshore. Numerous showers and scattered storms expected across the waters. && .PRELIMINARY POINT TEMPS/POPS... DAB 72 88 73 91 / 30 60 20 60 MCO 73 89 74 91 / 20 60 20 60 MLB 73 87 72 91 / 30 70 20 60 VRB 73 87 72 90 / 40 70 30 60 LEE 74 88 75 90 / 20 50 20 60 SFB 73 88 75 91 / 20 60 20 60 ORL 73 88 75 92 / 20 60 20 60 FPR 72 87 72 91 / 40 70 30 60 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ Smith/Pendergrast
Area Forecast Discussion
National Weather Service Riverton WY
228 PM MDT Mon Jun 17 2019 .SHORT TERM...(This evening through Tuesday) Scattered showers/storms are more abundant this afternoon across the forecast area as heavy rainfall and mainly small hail are likely with most storms that develop. The short term models continue to indicate that the low to mid level southeast flow will be the steering mechanism for the expected southeastward movement of the storms in a continued low wet bulb environment this afternoon/mid evening. The HRRR model seems to have a decent handle on the convective initiation and will trend more with the HRRR involving placement and timing of the storms through 03Z tonight. Weak ridging is still progged by the models to take shape after 03Z tonight, with precip expected to end in all areas except the far northwest and south central sections of the state by after 03Z tonight. May have to keep in a slight/isolated mention of showers/storms in the far south sections through 06Z tonight. By Tuesday, the trending still looks in favor of lessening chances of showers/storms as slightly drier air builds into the region from the west/northwest. Will lower pops somewhat into the lower chance category, but still expect early afternoon through mid evening scattered storms across much of the same area on Tuesday as today. .LONG TERM...Tuesday night through Monday Tuesday night will see a change in the pattern. With more zonal flow coming into the west expect a good amount of dry air advection in the upper levels. This will help finish off any convection from west to east overnight as the dry air caps everything off. Wednesday will be mostly dry and the warmest day of the extended period. I say mostly dry as a shortwave will move across the north ahead of our next weather system. This instability will allow for showers and thunderstorms across the northern portions of the FA during the afternoon. Widespread gusty west winds will occur Wednesday afternoon as the low begins to move out of Canada. Winds will be strongest west of the Divide reaching the 40 to 45 mph range. East of the Divide will se stronger winds as well but remain in the 30 to 40 mph range. Thursday will be mostly dry for the central and south with breezy to windy conditions and low afternoon relative humidity. High temperatures will be mild to warm in the central and south. In the north, isolated to scattered showers and storms will occur in the afternoon and night. A cold front will be positioned in the north which would help with storm formation. Cooler high temps in the north Thursday. Winds will be strong again on Thursday afternoon with dry conditions in the south. Models continue to show a developing trough over the northern Rockies Friday through Saturday. This will increase the chance of showers and storms over the region. Good news is it looks like the front will push through the FA overnight Thursday into Friday so the chance for severe weather will be diminished. Cooler air will move in as well bringing high temps below normal Friday and Saturday. Sunday looks to be warmer with a chance of showers and storms in the west with lesser coverage east of the divide. Southwest flow aloft next Monday with breezy conditions ahead of the next weather system. Best chance of showers and storms will be in northwest and northern WY with lesser coverage elsewhere. Seasonably warm next Monday. && .AVIATION...For the 00Z TAFS through 00Z Tuesday night VFR conditions will prevail at the terminal sites. Showers and thunderstorms are expected to continue this afternoon through midnight tonight. Main aviation threat near these storms will be variably gusty wind to 30 knots. Local MVFR conditions will occur with the stronger storms with reduced visibilities and lower ceilings. Showers and thunderstorms will be decreasing after 06Z Tue. && .FIRE WEATHER... Expect scattered showers/storms through late evening tonight and more development across much of the same areas from north of a Jackson to Lander to Casper line, extending southeast through Tuesday evening. Isolated showers/storms may linger past midnight east of the Divide, tonight. Expect winds to remain generally light, except in and near storms through the time period. Smoke dispersion values will be fair to good through Tuesday, with trending indicating that there will be lower relative humidity values, increasing winds and lower showers/storms chances Wednesday and Thursday. && .RIW WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Troutman LONG TERM...Hulme AVIATION...Hulme FIRE WEATHER...Troutman
Area Forecast Discussion
National Weather Service Blacksburg VA
858 PM EDT Mon Jun 17 2019 .SYNOPSIS... A stationary front will linger over the Mid Atlantic this week. Waves of low pressure should track eastward along this front, which will provide a daily threat of showers and thunderstorms. Warm and humid conditions should continue through this time. && .NEAR TERM /THROUGH TUESDAY/... As of 900 PM EDT Monday... Clusters of showers and isolated thunderstorms continue to linger across southern/southwest sections this evening, mostly in areas that have not been worked over from earlier convection. Also appears that a convectively induced wave looks to be lingering along the foothills per broad turning seen on radar loops. Latest HRRR keeps some of this convection going for a few more hours before loss of heating/instability finally cause most showers to fade around midnight. However can see some of this continuing to spread east via redevelopment given the current lingering axis of higher Cape values in the southeast. Expect these mostly to be heavy rain produces per Pwats nearing 1.5 inches this evening. Therefore keeping likely pops going in spots over the south with low chances north to Highway 460 attm. Muggy lows in the 60s with some staying above 70 with some patchy fog around. Previous discussion as of 200 PM EDT Monday... The 12Z RNK sounding reveals a precipitable water of 1.20 inches and a considerably high freezing level. Wind shear is rather light, so the threat for any severe weather this afternoon appears marginal. However, thunderstorms that develop will be quite efficient in producing rainfall. CAPE should exceed 2,000 J/kg during the next couple hours, which will increase the expected coverage of storms. By tonight, the showers and thunderstorms should wane as instability decreases. Leftover cloudiness from earlier convection and the humid air mass will keep low temperatures in the 60s. More showers and thunderstorms appear likely for Tuesday as a shortwave upper level trough moves overhead. As a result, POPs were increased across the CWA. Again, heavy rainfall will likely occur in the storms due to the high freezing levels and above average precipitable water. SPC also maintains a marginal threat of severe weather for Tuesday. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 300 PM EDT Monday... Showers/Storms associated with upper level shortwave trough are expected to move east of the forecast area after midnight Tuesday, increasing stability and west-northwest downslope wind bringing an end to the convective threat. Will maintain slight chance pops to account for any lingering showers late Tuesday night into Wednesday morning but think overall chance for rain will end with passage of the shortwave and onset of negative vorticity advection (NVA). Wednesday will likely be a down day with respect to thunderstorm threat as we will be in the wake of the departing short wave. Surface heating and may initiate some isolated showers/storms Wednesday, but coverage sub-par since forcing mechanism limited to just the heating of the day. Better opportunity for showers/storms is expected to occur Thursday associated with dynamic lift from another short wave trough...this trough moving quickly from west to east via modest zonal flow. Elevated PWATs of 1.25 to 1.75 are forecast the entire week, so showers/storms that do occur will be rain efficient. Surface dewpoints are also forecast to remain at or above 65 so it will remain muggy, temperatures ranging from the 60s at night to the 80s during the day. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 330 PM EDT Monday... Expect a drying trend for Friday and Friday night as winds likely to remain northwesterly in the wake the passage of Thursday`s short wave trough. Plenty of mid level drying progged as well, so shower/storm activity would be unfavorable. Can`t rule out a rogue shower far west for any upstream activity which may cross the Ohio Valley, but think Friday as a whole for our forecast area will be dry. The drying is expected to be short-lived however as upper ridge builds in again by Saturday along with return of deeper moisture for the entire weekend. Thus chances of showers/storms increase Saturday and more so into Sunday. Near seasonal temperatures and increasing humidity as well through next weekend. Generally pretty good agreement in the guidance for these trends through the upcoming weekend. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... As of 710 PM EDT Monday... Showers and isolated thunderstorms will continue to linger into this evening before slowly fading to mainly VFR with the exception of patchy fog overnight. Thus plan to continue either a vicinity mention or TEMPO in some lower conditions in residual showers espcly south and west through about midnight. Expect areas of MVFR to IFR conditions in fog/stratus overnight espcly in spots that received earlier heavy rain. However debris clouds as well as upstream cloud cover could inhibit it to some extent. VFR conditions should resume for Tuesday morning, but showers and thunderstorms appear likely to fire again in the afternoon as a wave of low pressure passes overhead. Coverage of this convection could become rather widespread with the potential for MVFR conditions, gusty winds, and turbulence at all TAF sites. Therefore given higher confidence included either prevailing showers/storms or vicinity mention for convection Tuesday afternoon. Extended Aviation Discussion... A stationary front over the Mid Atlantic along with waves of low pressure tracking eastward along this boundary should keep an active weather trend through Thursday. Showers and thunderstorms will likely develop each afternoon and evening, which will produce areas of MVFR and heavy rainfall. MVFR or IFR conditions from fog or low clouds may also occur during the late night hours due to increasing moisture. By Friday, a cold front should shove the stalled boundary offshore, and drier air from high pressure will bring VFR conditions through Saturday. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...PW NEAR TERM...JH/PW SHORT TERM...PM LONG TERM...PM AVIATION...JH/PW
Area Forecast Discussion
National Weather Service Las Vegas NV
800 PM PDT Mon Jun 17 2019 .SYNOPSIS... The region will dry out by mid week and temperatures will gradually warm to above normal. Another weather disturbance will bring gusty winds across the region Thursday and drop temperatures to below normal by Friday. && .UPDATE...Showers and thunderstorms look to be losing energy relatively quickly as the sun begins to set and stability increases. Lingering shower activity in southeastern California and northwestern Arizona should cease in the next few hours. Similarly, skies are expected to clear out overnight. Temperatures remain in the mid-90s at the moment, but substantial cooling will take place when the skies clear, as noted in the current hourly grids. No changes to the forecast necessary at this time. && .PREVIOUS DISCUSSION...152 PM PDT Mon Jun 17 2019. .DISCUSSION... Shower activity from the shortwave disturbance is generating a fair amount of showers and isolated thunderstorms across the area. This activity will begin to wane as we head into the evening hours. One concern is that much of the activity over central Nye and Lincoln Counties may kick out a moderate strength outflow boundary that will head south and affect the central to southern parts of our area including the Las Vegas Valley this evening. The HRRR model has been consistent in forecasting this feature. The winds are not expected to be severe or damage producing. However, if it does materialize it could bring wind gusts of 30-40 mph and have an impact on air traffic at McCarran along with any outdoor activities planned this evening. Beyond this evening, the upper level pattern remains persistent with the CWA caught in the deformation zone as a upper low forms off the southern California coast. Residual moisture in the area will keep the threat of afternoon showers across the central and northern portions of our area. There is likely to be some variability in the day-to-day location of this activity, but generally in a east-west band across the central part of our CWA. Toward the end of the week a broad upper low will dive into the Great Basin region mainly bringing gusty southwest winds across our area. Models are getting more consistent in indicating that wind advisory criteria may be possible Thursday across the Mojave Desert with gusts up to 40-45 mph. By late Thursday into Friday, a surface cold front will push into the region dropping temperatures 7-10 degrees by Friday afternoon. Thereafter, expect dry, northwest flow through the weekend. && .FIRE WEATHER... Temperatures will gradually warm up through mid week and afternoon relative humidity will fall to single digits across the deserts. Expect these conditions to dry the near-critical fuels further this week. Critical or near-critical conditions may develop later this week as a weather disturbance brings gusty winds to the region Thursday. && .AVIATION...For McCarran...Easterly winds will gradually give way to southwesterly winds this evening following the typical pattern. There remains a likely scenario where thunderstorm activity north of Las Vegas kicks out an outflow boundary that will bring gusty north winds to the terminal around 5 UTC and last an hour or two before returning to southwest. Updates to the TAF will be made if this scenario becomes more likely. Beyond this evening, chances for thunderstorms farther north will decrease on Tuesday, leading to a more typical wind regime of light easterly during the day becoming south southwest at night. For the rest of southern Nevada, northwest Arizona and southeast California...Showers and thunderstorms over Lincoln and central Nye Counties will continue through sunset. There remains a likely scenario where these thunderstorm kick out an outflow boundary that will bring gusty north winds southward across southern Nevada and the Colorado River Valley early this evening. This will need to be watched and area TAFs will be updated as needed. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ UPDATE...Varian DISCUSSION...Lericos For more forecast information...see us on our webpage: or follow us on Facebook and Twitter