Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/15/18

Area Forecast Discussion
National Weather Service Albany NY
1011 PM EDT Tue Aug 14 2018 .SYNOPSIS... n upper level low pressure system will slowly move eastward across the region overnight with mainly isolated showers. A cold front will cross the region late tomorrow bringing another chance of showers and thunderstorms mainly across northern areas. Mainly fair and dry weather is expected most of the day on Thursday with above normal temperatures, especially from the Hudson River Valley eastward. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... As of 1010 PM EDT...The Flash Flood Watch for the Lake George Saratoga Region, Mohawk Valley, Sacandaga Region, Schoharie Valley, Greater Capital District, Eastern Catskills, Mid Hudson Valley, and the Taconics has been canceled. The latest RAP and satellite imagery shows the closed/cutoff low over eastern NY. Isolated to scattered showers and thunderstorms have pinwheeled around the edges of the forecast area. We have been spared the heavy rainfall compared to what WFO BGM has received, and the Flash Flood Watch has been canceled. The 01Z RAP SPC Mesoanalysis still indicates MLCAPE values of 500-1000 J/kg over the forecast area, so we kept isolated thunder in the forecast until midnight. The instability should wane and spokes of vorticity around the upper low could continue showers into the early morning hours. An isolated threat was continued until 06Z-08Z. PWATS remain high at 1.60" per the latest 00Z KALY sounding, but should lower overnight. Clouds will likely become variable with some patchy fog especially where rainfall has occurred and with the light to calm winds. Lows will be mainly in the lower to mid 60s with a few upper 50s over the mtns. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... For Wednesday more wet weather is possible mainly across northern areas as a cold front drops southeast from the Saint Lawrence Valley. PWATS Wednesday afternoon are generally under 1.5 inches except across northern areas where they are as high as 1.75 inches. Storms should be moving fairly fast Wednesday afternoon based on the H7 flow, generally at 30 to 40 kts. MLMUCAPES are generally 1000 to 3000 J/KG across much of the region with 0-6 km bulk shear 25 to 30+ kts. H7-H5 lapse rates are generally 6 to 6.5 C/km. So some stronger storms are certainly possible Wednesday afternoon especially across northern areas where SPC has a marginal risk in effect. Highs on Wednesday will be in the upper 70s to upper 80s. Wednesday night looks mainly dry as a weak ridge of high pressure tries to build into the region. Lows will be in the upper 50s to upper 60s. On Thursday expect a mostly dry day except cannot rule out a shower or thunderstorm mainly across western areas during the afternoon as a warm front will be lifting northeast from the Ohio Valley. Highs will be in the upper 70s to around 90. For Thursday night there will be a chance of showers across the northwest half of the forecast area as the warm front moves into central New York by Friday morning. Lows will be in the mid 60s to lower 70s. Friday looks to be another active day as showers and thunderstorms will become more numerous during the day with the warm front lifting northeast through the forecast area as a cold front approaches from the eastern Great Lakes with low pressure tracking across southern Canada. PWATS rise to over 2 inches across much of the region on Friday so have once again introduced the mention of heavy rain. MLMUCAPES rise to 1500 to 4000 J/KG Friday afternoon, 0- 6 km bulk shear 20 to 35 kts, H7-H5 lapse rates 5.5 to 6.5 C/km. So some stronger storms are possible once again. Overall during the short term period expect temperatures to average above normal with precipitation near normal to slightly above normal as well. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... This period will be marked by unsettled conditions at each end with a dry section in the middle between systems. Thunderstorms may be a threat, but along with limited sunshine and atmospheric momentum, instability will also be limited. It will feel as it the middle of summer, with moderately high humidities and high temperatures mainly in the upper 60s to lower 80s range each day, and lows mostly from the upper 50s to the lower and mid 60s. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Upper level low now over Mohawk valley will continue to slowly move eastward across the region this evening. Ceilings and vsibilities will generally be VFR this evening, but scattered showers and thunderstorms may impact the TAF sites through midnight. Timing of showers/storms is uncertain so VCSH included in the TAFs. Mainly VFR should occur in the evening, but areas of fog and/or stratus are expected to develop after midnight. best chance for fog/stratus at the TAF sites is at KGFL and KPSF. VFR conditions all TAF sites again by 14Z Wednesday. Winds will be light and variable tonight. By Wednesday afternoon, winds will be out of the west around 10kts. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Slight Chance of SHRA...TSRA. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: High Operational Impact. Definite SHRA...TSRA. Friday Night: Moderate Operational Impact. Chance of SHRA. Saturday: Moderate Operational Impact. Chance of SHRA. Saturday Night: No Operational Impact. Slight Chance of SHRA. Sunday: No Operational Impact. Slight Chance of SHRA...TSRA. && .FIRE WEATHER... An upper level low pressure system will slowly move eastward across the region into tonight, bringing occasional showers and scattered thunderstorms. Thunderstorms will be capable of producing locally heavy rainfall with flash flooding possible. A cold front will cross the region late Wednesday bringing another chance of showers and thunderstorms mainly across northern areas. && .HYDROLOGY... The Flash Flood Watch has been canceled. River flows continue to lower overnight across the Hydro Service Area. Additional rainfall tonight will be light with less than a quarter of an inch from any showers. Widely scattered showers and thunderstorms will be possible associated with a cold front passage Wednesday afternoon into Wednesday evening. Then, more unsettled weather is expected towards the end of the week as another low pressure system affect the region. Showers and thunderstorms with locally heavy rainfall will be possible again Friday afternoon into Friday evening. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...11/Wasula NEAR TERM...Wasula SHORT TERM...11 LONG TERM...ELH AVIATION...SND FIRE WEATHER...11/JPV HYDROLOGY...11/JPV/TAW
Area Forecast Discussion
National Weather Service Denver/Boulder CO
951 PM MDT Tue Aug 14 2018 .UPDATE... Issued at 945 PM MDT Tue Aug 14 2018 The late afternoon and evening strong to severe storm activity along the Front Range has diminished considerably with the last remaining t-storms continuing to track east-southeast away from the Denver metro area into increasingly stable boundary layer air. Eruption of today`s hail and heavy rain storms coincided with the passage of a shortwave trough which GOES IR/Water Vapor imagery now show over far eastern Colorado/Nebraska Panhandle. Clearing, albeit gradual, is now underway, although mid-level moisture visible on 6.19 and 10.35um GOES sat loops streaming up from the Desert Southwest may keep at least high cloud cover around through Wednesday morning. In addition, low-level moisture feeding up into southeast sections of the CWA may once again result in patchy to areas of fog towards dawn. Do not believe the fog tonight will extend as far west into portions of the I-25 corridor as it did last night. Other changes to tonight`s forecast include only minor adjustments to wind and temperature fields. && .SHORT TERM...(This evening through Wednesday) Issued at 222 PM MDT Tue Aug 14 2018 Thunderstorms will continue to form over the mountains and foothills this afternoon. Once the Urban Corridor and near by plains destabilize more, the storms will be able to progress eastward. Latest RAP and HRRR showing CAPE of 800-1400 J/kg in the foothills and across the Urban Corridor late this afternoon and evening. This combined with precipitable water values around an inch and lift from a trough over Montana and Wyoming is expected to produce scattered thunderstorms over the mountains, foothills, and Urban Corridor. The airmass becomes more capped and more stable across the eastern plains. Expect storms to die off as they move east of the Urban Corridor this evening. For Wednesday, a boundary will be over eastern Colorado. To the west of it, models indicate there will be drier air. Also, most of the models keep convection south of I-70 Wednesday. However, there should be enough convergence along the boundary, moisture, and instability to produce a few storms. Flow aloft will increase and produce better shear. This along with CAPE of 1000-1500 J/kg could produce a few severe storms Wednesday afternoon over the eastern plains. .LONG TERM...(Wednesday night through Tuesday) Issued at 222 PM MDT Tue Aug 14 2018 By Wednesday night the upper ridge will be over New Mexico and extend east over the Gulf coast. Specific humidity values will increase with PW values reaching to above an inch by late Wednesday. For Wednesday night storms will mainly be focused over the higher terrain of the Palmer divide with some cells being able to move over the plains with the breakdown and northern movement of the surface low. These storms will mainly be capable of gusty winds and small hail. For Thursday and Friday the upper ridge will retrograde back to the West and North in Colorado. This will help to bring increased NW flow over the state. A cold front will push through over the NE plains Thursday afternoon that could produce enough CIN around peak heating time to inhibit much convective potential outside of the higher elevations of the mountains and foothills. Temperatures Thursday will be hovering just around normal for this time of year with highs in the mid to upper 80s. For Friday, some fog could be possible over the plains during the early morning hours as moisture will be high and temperatures slightly cooler in the post frontal airmass. By the late morning hours a disturbance embedded in the NW flow aloft will move over helping to introduce lift for storm development across the plains by the late afternoon hours. Instability is better over the far eastern plains after convective initiation with CAPE in the 1000-1500 j/kg with just around 500 over the Urban Corridor according to the GFS. PW values remain over an inch with steering flow only 10-15 kts. This indicates that any storms that do form will be slower moving and could produce a quick half inch in less than 30 minutes under the stronger cells. Friday will be slightly warmer than Thursday with highs in the upper 80s. For the weekend and into the start of next week the upper ridge will fully transition to over the western CONUS leaving Colorado in increased NW flow. This will allow for the influx of upper waves and fronts to bring cooler air and increased chances of showers and thunderstorms to the region. The first shortwave will move through Saturday into Sunday bringing storms Saturday late afternoon and evening capable of brief heavy rain and small hail. As the shortwave moved over forcing could continue storms overnight into Sunday. A cold front is set to move out of WY into CO Monday ushering in continued cooler temperatures with highs possibly in the 70s by Monday. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 945 PM MDT Tue Aug 14 2018 Storms for the most part have moved east of the Denver metro area and ceilings have begun to rise with the development of a drying south-southwest drainage wind of 5-12kts. Can`t rule out a stray rain shower at any one of the Denver area terminals before 06z tonight, then gradual clearing thereafter. Restrictions due to fog are not expected tonight. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Baker SHORT TERM...Meier LONG TERM...Bowen AVIATION...Baker
Area Forecast Discussion
National Weather Service Fort Worth TX
856 PM CDT Tue Aug 14 2018 .UPDATE... Only minor adjustments to the forecast were necessary this evening to account for temperature/sky trends. Precipitation has completely exited the area to the northeast, along with the upper low which brought us our several days of rainfall and slightly cooler weather. While the upper low is now centered near Kansas City, the elongated trough axis is still draped to the southwest through western OK and the TX Panhandle. This has contributed to numerous severe thunderstorms developing in Central Oklahoma this evening. The ongoing storms in Oklahoma really are the main focus through the short term, as it`s possible they encroach on the Red River very late tonight. While I`ve been unable to locate a single CAM that hints at this possibility, due northerly Corfidi vectors of 20 kts and strong WAA fields in the 925-700mb layer would suggest there is a potential for a congealed convective cluster to make a dive southward during the overnight hours. Recent objective analysis indicates around 1500 MUCAPE is still available across southern Oklahoma which a complex could ingest while fueled by convergence at the nose of a 30 kt low level jet. Overall, it seems the chance of convection reaching North Texas prior to dissipating is relatively low, but not low enough to remove the 20-30% PoPs in place for our Red River counties prior to daybreak. Will continue to monitor hourly short-term guidance for possible southward trends in model solutions. -Stalley && .AVIATION... /Issued 636 PM CDT Tue Aug 14 2018/ /00z TAFs/ Lingering rain showers have all exited the DFW area as a band of mid-level moisture accompanies an upper low northeastward. The upper trough axis remains to our west, however, and is aiding in the ignition of storms across Central Oklahoma this evening. While some of this activity may drift towards the Red River late tonight or early tomorrow morning, it will remain well north of the DFW area TAF sites. The entire TAF period will consist of dry conditions with predominantly VFR cigs. However, a few hours of MVFR cigs around 2500 ft may materialize at Waco around daybreak tomorrow morning. Prevailing south winds around 10-15 kts will continue through Wednesday with SCT diurnal cumulus. -Stalley && .SHORT TERM... /Issued 357 PM CDT Tue Aug 14 2018/ /Through Tonight/ Water vapor imagery shows the upper low over the Plains quickly pulling away to the northeast. A persistent band of strong isentropic ascent extending from the Metroplex northeast is slowly lifting away with precipitation coverage on a downward trend. For the remainder of this afternoon and evening, there will still be weak ascent associated with the larger trough spreading through North Texas, so at least isolated showers and perhaps a thunderstorm will remain possible. We`ll hang on to 20% PoPs mainly along and north of I-20 through the early evening hours. Later tonight, low level flow will veer to the southwest with a fairly decent band of convergence setting up across Oklahoma during the overnight hours. Showers and thunderstorms will likely be ongoing to our north, but strong low level warm advection will extend all the way down into the Red River counties. Despite some drying expected to occur, there may be sufficient forcing for a few showers and thunderstorms during the early morning hours across our northern counties. Otherwise, partly to mostly cloudy skies will prevail with temperatures in the mid 70s. Dunn && .LONG TERM... /Issued 357 PM CDT Tue Aug 14 2018/ /Wednesday through Monday/ After an extended period of high rain chances across North and Central Texas, it appears that most of the region will get a respite from the rain/storms. Areas near and north of I-20, however, will still have the potential for convection through the weekend as we transition to northwest flow aloft. Temperatures will trend back towards seasonal values for areas that have seen rain over the past couple of days and heat index values will climb above 100 degrees. Mild conditions will be the theme to start Wednesday morning as low level flow will be unseasonably strong. RAP and NAM 925mb wind progs advertise nearly 40 knots of low level flow overspreading much of the area. While limited to some degree due to the onset of nightfall, mixing should help temperatures stay in the mid to upper 70s and this should diminish an appreciable fog threat---outside of low-lying/sheltered areas. The more noteworthy impact that the winds may have is for the sustenance of convective cells to the south of the Red River. Higher resolution NWP does not show much in the way of rain/storms, but given the strong wind field and subsequent isentropic ascent, a 20 PoP as far south as the Highway 380 corridor seems warranted. Rain chances should wane some through the day, though I`ll keep low PoPs along the Red River in the event that outflow lingers late into the afternoon and becomes a focus for renewed convection. Hot conditions will be the next story on Wednesday as a weak frontal boundary will attempt to sag southward towards the Red River. Most guidance keeps the front north of the Red River, but the position of the boundary will need to be monitored. Surface winds preceding the front Wednesday afternoon should veer slightly to the southwest, which may help promote greater temperatures. The recent rains should help to keep temperatures from soaring too high, but it`ll likely feel quite humid outside with the mid- August sun and plenty of water for evapotranspiration. High temperatures areawide should climb into the mid to upper 90s with heat index values up to 105 degrees in some spots. Thursday morning should feature slightly weaker flow...but interestingly enough...lapse rates---per the NAM---are a tad steeper. Large scale lift from any synoptic scale feature is pretty indiscernible right now, but there may be some slight isentropic upglide along the Red River. While large scale synoptic forcing looks subtle, decent lapse rates and a little moisture can still result in some precipitation. Probabilistic guidance from both the EPS and GEFS do not offer much in terms of accumulated QPF along the Red River on Thursday morning and into the afternoon, so I`ll place a silent 15 PoP across the Red River Valley. Surface winds turn more to the southwest on Thursday which should promote another hot day. Temperatures will climb a little higher than Wednesday and with plenty of rain the past few days...there should be plenty of evapotranspiration to result in humid conditions. The warmer conditions equates to heat index values closer to 105 degrees on Thursday. Northwest flow aloft becomes a bit more established through the day on Friday and both NAM and GFS guidance suggest that a compact shortwave trough will dive southeastward and graze the Red River zones. Given that this feature is forecast to move through during the late morning to early afternoon hours on Friday, I`ll show a slight chance for rain/storms a bit farther south. Forecast soundings in the afternoon indicate that the boundary layer may become pretty hot and well mixed...supporting a risk for strong downburst winds. Otherwise, temperatures will be close to seasonal values for mid-August. Heat index values will also be close to 105 degrees and if this appears likely...a small Heat Advisory may be needed for portions of North Texas. Saturday will feature low rain chances during the morning hours before some slight mid-level height rises overspread from the west. Mid and upper level clouds may continue invade from the north which may help keep temperatures a few degrees lower. Subsequently, heat index values are not forecast to be quite as high during this time...with values just below 105 degrees. For Sunday and beyond, rain chances will ramp back up as a decent trough begins to take shape to the north and west. The best rain chances will be initially along the Red River and across the Big Country. There is pretty decent agreement between the deterministic GFS and ECMWF in plowing a front through most of the area early next week. The ECMWF is a lot more aggressive and blasts the front all the way towards the upper TX coast while the GFS slowly brings the front back to the north a little sooner. Regardless of the solution, it looks like there will be another period of below normal temperatures and rainfall for a good portion of the area. Bain && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 76 96 78 98 79 / 10 10 5 10 5 Waco 76 95 76 98 77 / 5 10 5 5 5 Paris 74 90 74 95 76 / 20 20 20 20 10 Denton 75 95 77 98 76 / 20 10 5 10 10 McKinney 75 94 76 96 77 / 20 10 5 10 10 Dallas 77 96 79 98 80 / 10 10 5 10 5 Terrell 76 91 77 96 77 / 10 10 5 10 5 Corsicana 76 92 76 97 77 / 5 5 5 10 5 Temple 75 96 75 98 76 / 5 5 5 5 5 Mineral Wells 73 97 74 97 76 / 10 10 5 5 5 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 26/82
Area Forecast Discussion
National Weather Service Glasgow MT
826 PM MDT Tue Aug 14 2018 .DISCUSSION... Evening update... Day crew added "haze" to the grids for tomorrow: either haze or smoke will impact visibility tomorrow (it should be noticable to the average person that it`ll be hazy or smoky out). This will show up with the evening update. For KGGW & KOLF, added haze to the TAFs beginning at 6z tonight, based largely on the 25 micrograms/m^3 contour on HRRR Smoke (left it out--for now-- for KGDV & KSDY). Otherwise, going forecast seems to be on track with minor tweaks to POPs in southern Prairie and southern Wibaux Counties in case something strays in, and to temperatures. Avery Previous discussion... Weak upper low over SE Montana/northern WY will drift southeast tonight and should be in western South Dakota Wednesday. An upper ridge will build over Montana in it`s wake allowing the airmass to warm. This ridge will be in control of the area`s weather through Friday then another disturbance will move through. With the upper ridge moving in Wednesday, skies will be mainly clear with temperatures most places in the 90s. Fire weather concerns should be minimal as winds will be light. On Friday, a cold front will approach the area from the northwest. Pre-frontal compressional warming should take place and warm temperatures well into the 90s. No 100 degree plus temps are expected with 850 mb temps remaining below 30C. The models are differing on the feeble chances of showers for the weekend. The GFS being a bit fast, brings the best chances Friday evening, while the ECMWF brings it through Saturday afternoon. Have lowered the pops for most periods and their spacial coverage, but keeping them for Saturday afternoon. Typically we`ll get a moisture tap into monsoonal moisture from the desert SW, but with a WNW flow, this will likely not happen and be kept south of us. TFJ && .AVIATION... Flight Category: VFR, outside chance of MVFR. Visibility: Haze or smoke coming from the fires in western Montana, Idaho, Washington, British Columbia, and California will lower visibilities some, which could briefly lower visibilities into MVFR range. Discussion: An upper ridge to our west will gradually push east allowing for mainly clear skies. Haze or smoke will lower visibilities some tomorrow, and possibly beyond that. Area winds: Generally light and variable through early Wednesday, then becoming light from the south to southeast. Avery && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$
Area Forecast Discussion
National Weather Service Green Bay WI
651 PM CDT Tue Aug 14 2018 Updated aviation portion for 00Z TAF issuance .SHORT TERM...Tonight and Wednesday Issued at 350 PM CDT Tue Aug 14 2018 Forecast concerns are scattered thunderstorms across northern Wisconsin into the early evening, patchy dense fog overnight and scattered showers and isolated thunder again on Wednesday. Latest radar and satellite trends indicated a broken area of thunderstorms along a cold front stretching from the eastern UP to north of MSP late this afternoon. Storms have been somewhat pulse-like in nature and overall poorly organized. Low-level moisture pooling right along and just ahead of the front has allowed SBCapes to creep into the 1500 to 2000 J/kg from Northern Wisconsin to MSP with modest mid-level lapse rates. Deep layer shear is modest generally 15 to 20 kts except right along the UP/WI border where values are closer to 30 kts. HRRR and NAMNest are generally similar advertising current convection to be at its strongest between now and perhaps 23 UTC before quickly waning after sunset given weak upper-level support. The bulk of this activity is expected to impact mainly areas north of highway 64. The storms are not expected to reach severe limits before dissipating, but are capable of producing perhaps some small hail and brief gusty winds especially across far northern Wisconsin for the next couple of hours. Weak surface boundary is forecast to slowly drop south into central and eastcentral Wisconsin on Wednesday morning. In addition, weak nearly cutoff upper-level low pressure will also drift into southwest Wisconsin by late morning with boundary layer winds turning SE ahead of it. The combination of these features should locally enhance low-level convergence across central Wisconsin by midday. Combination of more focused low-level convergence, residual low-level moisture and increasing insolation later in the morning, should allow for a disorganized area of showers and isolated thunderstorms to develop around midday Wednesday. Again, deep layer shear will be weak thus storms are expected to be disorganized and pulse-like in nature with brief heavier downpours possible. Overnight tonight, patchy dense fog is also possible once again mainly across northern and central sections especially in areas that receive some appreciable rainfall this evening. .LONG TERM...Wednesday Night Through Tuesday Issued at 350 PM CDT Tue Aug 14 2018 Not expecting any high impact weather through much of the extended forecast. There may be a few showers and thunderstorms over next couple days, with a better chance of more widespread showers and thunderstorms very late in the weekend into early next week. Near normal temperatures can be expected through Thursday before above normal temps arrive over the weekend. Late in the forecast period, trends are toward temperatures that cool to near normal early next week. Wednesday night through Thursday night: This time period will consist of increased cloud cover along with intermittent rain showers. Overall instability looks to be lacking, which would only favor a few afternoon rumbles of thunder, mainly if there are any breaks in the cloud cover. The main driver of these rain showers and possible thunderstorms will be a couple shortwave troughs expected to slide through the area. The first wave is expected to slide through northern Illinois Wednesday night into southern Lower Michigan by Thursday morning. Thursday afternoon would be the next chance, and probably the best chance, of seeing some pop up afternoon rain showers and perhaps a rumble of thunder; however, the CWA is expected to between two shortwaves at that time, yet still in a general troughing pattern. The next shortwave, is progged to slide mainly to the south of the CWA Thursday night, perhaps only bringing a small chance of rain showers to the Fox Valley. Not expecting a drought buster, just some generally light rain showers. Highs will be near normal for this time period with highs mainly in the 70s and overnight lows in the 50s to around 60. Friday through Sunday: The main trough axis and the aforementioned shortwaves will shift off to the east of the area through this time period. This will allow for a ridging pattern to set up across the CWA, both aloft and at the surface. Winds will remain light and there may be some radiation fog formation at night with clear skies and calm winds, especially inland. Daytime highs will be above normal with most locations expected to reach into the 80s, while overnight lows are expected to drop into 50s to around 60. Sunday night through Tuesday: Things will become more active for this time period as a broad troughing pattern is expected to dig into much of the central and eastern CONUS. This is indicated by each of the long-range models. There continue to be some differences in timing, so exact detail will need to be pinned down closer to this rain event. Models currently have an associated cold front that would slide through the area Sunday night through early Monday afternoon. The timing difference is largely between the EC/GFS, where the GFS is more progressive at moving the front through the CWA. This is something to monitor, as seems to rush things a bit faster later in the summer season into the early fall. Regardless, Sunday into Monday, looks to be fairly unsettled. Subsidence associated with high pressure on the back side of the front, will allow for clearing conditions and quieter weather Monday night into Tuesday. Temperatures will cool to normal or possibly a bit below, depending on how strong/deep the trough is across the area. && .AVIATION...for 00Z TAF Issuance Issued at 650 PM CDT Tue Aug 14 2018 As of 23Z a cold front was stalled across northern Wisconsin and showers and thunderstorms in the north were weakening or moving out of the forecast area. There should be a period of quiet weather once the showers and storms have departed, but fog is then a concern due to light winds. Cloud cover could hamper fog development, but this afternoon`s rainfall may counter that across the north. Kept the mention of fog at all TAF sites that was in the previous forecast. Precipitation timing and potential are the main concerns on Wednesday as a mid level short wave approaches from the southwest. Mesoscale models bring convection into the area from the southwest during the morning as more showers and storms fire in the vicinity of the frontal boundary. The morning rain is then forecast to push east as more significant convection fires in central Wisconsin during the afternoon. Confidence in the timing and exact location of Wednesday`s showers and storms is low. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....ESB LONG TERM......Cooley AVIATION.......MG
Area Forecast Discussion
National Weather Service Medford OR
901 PM PDT Tue Aug 14 2018 .DISCUSSION...No big updates required this evening. Weather is fairly quiet this evening but not lacking impact. Smoke is thick in many areas tonight, after another day of fire activity around the region. Air quality in Medford is now in the "hazardous" category, one of the highest PM2.5 readings we`ve registered. Better but still unhealthy conditions are being observed towards the coast and east of the Cascades. The latest HRRR smoke model run, and atmospheric conditions, suggest smoke will linger near the surface overnight, so don`t expect much improvement. Thunderstorm threat is the other main element we`re focusing on. Midlevel moisture is evident on the evening satellite imagery over Northeastern California. No lightning has been observed yet, but convection-allowing models suggest that thunderstorms are possible east of the Cascades by early Wednesday morning. Particularly bullish on the thunderstorm threat later tonight are the NAM Nest and HRW NSSL models We are maintaining a Red Flag Warning from the Cascades eastward and in Northeastern California from now through Wednesday evening. Further west, there is greater uncertainty in lightning potential, and we have a Fire Weather Watch continuing there for Wednesday. Smoke coverage and intensity looks like a repeat of today`s situation, pending fire activity of course. Please see the previous discussion below for more details on the smoke and thunderstorms. && .AVIATION...For the 15/06Z TAFs...Along the coast widespread IFR/LIFR cigs and MVFR/IFR visibilities will persist through Wednesday with gradual erosion of coverage in the coastal valleys during the late morning and afternoon. Inland, for the Umpqua Basin, VFR conditions are expected throughout the TAF period. Elsewhere inland, widespread smoke from area wildfires is resulting in reduced visibilities. MVFR vsbys with local IFR vsbys will persist through the TAF period. -DW && .MARINE...Updated 800 PM PDT Tuesday, 14 August 2018...Relatively light winds and seas are expected through tonight. Coastal fog and low stratus will continue into Wednesday. Building northwest swell is expected Wednesday. A thermal trough will redevelop along the coast on Thursday, producing gusty north winds and steep seas into this weekend. Small craft advisory conditions are likely, with afternoon and evening gales possible Friday and Saturday south of Cape Blanco. Conditions are expected to improve early next week. - CC/DW && .FIRE WEATHER...Updated 100 PM PDT Monday, 13 August 2018... The main focus for this forecast cycle was on the potential for dry thunderstorms tonight and Wednesday east of the Cascades. The most recent model data shows more of a consensus of elevated convection firing off during the late this evening in northern California and working its way northward and westward to the Cascade Crest into the early morning hours of Wednesday. Also looked at the air mass profile over northern California and southern Oregon east of the Cascades, and there is definitely moisture aloft with a typical inverted V sounding up to 550 mb or so. Given a consensus for some isolated nocturnal thunderstorms with LAL 6 combined with near-record dryness, decided to continue the Red Flag Warning was appropriate for Fire Weather Zones 284 and 285 in California and Oregon Fire Weather Zones 624 and 625. We extended the area of the Red Flag Warning to include most of fire zone 623 and the far eastern portion of fire zone 617. We have also extended the timing of the Red Flag Warning for California Fire zones 284 and 285, to cover the entire thunderstorm event. There may be a break in thunderstorms Wednesday afternoon. However, by Wednesday evening, the isolated dry thunderstorm chances will return to those zones, so decided it made more sense to keep the warning going through the entire event. West of the Cascades, there is more moisture available for convection to initiate on Wednesday, but smoke may inhibit surface based thunderstorms. That being said, there is plenty of elevated energy that this shortwave can tap into to create more elevated and dry storms. Regardless of wet/dry thunderstorms, any lightning should be sufficient to see new starts. Thus, we are leaving the Fire Weather Watch for FWZ 280, 281, 621, 622, and most of 617. Thunderstorms are also in the forecast for the majority of the forecast area Wednesday except the coast and the Umpqua region. We won`t be completely done with thunderstorms Thursday, since the upper trough/low offshore will be slow to move inland. We have kept thunder chances in the mountains and over portions of northern Klamath and Lake Counties, but the dry thunderstorm threat will largely diminish. The upper trough/low should push through Friday and it should dry out and turn hotter again this weekend. Gusty southwest winds are expected across Modoc County and the relative humidities will be typical for this time of year. This means that conditions will be near critical on Thursday afternoon for fire zone 625. Otherwise, there is some potential for a period of offshore NE winds over SW Oregon and the western Siskiyou County mountains Friday into Saturday as a thermal trough sets up in northern California. -Schaaf && .PREV DISCUSSION... /Issued 243 PM PDT Tue Aug 14 2018/ DISCUSSION...Some tweaks were made to the going forecast today, but the general forecast remains the same. An upper low is positioned off the coast this afternoon, and we are under the influence of the south-southwest flow ahead of this feature. Moisture can be seen streaming northward toward us, and cumulus are already developing over northern California. Mid level moisture continues to rise tonight, and as a result, instability aloft also increases. Capes of 500+ J/KG are common on east side soundings tonight, and this is fairly impressive elevated instability for around here at night. Models remain somewhat split on the timing and strength of the last necessary ingredient: a trigger. It`s hard to make out any short wave activity over NorCal on this afternoon`s water vapor imagery, but it`s also not too hard to imagine something in there as there are fields of ACCAS on visible imagery. The GFS shows a rather broad area of vorticity moving over us tonight, whereas the NAM shows a more robust short wave arriving around dawn tomorrow. Both models key in on convective potential from eastern Siskiyou County northward into the Klamath Basin late tonight. Furthermore, forecast soundings show very dry low layers (inverted-V) with cloud bases at around 10,000 feet, and this indicates that any storms that do develop are very likely to be dry. As a result, we`ve pulled the area of isolated dry thunderstorms further westward tonight to around the Cascade crest and expanded the red flag warning to cover it. What storms do form overnight are likely to slide northward through the morning, and then there may be a break during the afternoon hours. However, models are consistent in showing another outbreak of convection late tomorrow afternoon and evening. This is again expected to be focused from the Cascades east, but the GFS continues to show the potential for some storms on the west side late in the day. Surface based instability could easily be limited by smoke coverage (which blocks sunlight and reduces instability), so storms west of the Cascades are by no means certain. Nevertheless, ignition efficiency is likely to be very high, and thus any lightning strikes would be problematic enough that, in our judgment, it`s worth keeping a fire weather watch in place. To complicate matters even further, any storms on the west side will have more moisture to work with and thus could be on the wetter side IF they are able to tap into boundary layer moisture, but if smoke limits surface instability and they storms remain elevated, they would be on the dry side. As the upper trough begins to come inland later Thursday, we could see a repeat of thunderstorms in roughly the same areas. However, unlike tomorrow, drier air starts working in from the south on the east side and instability on the west side decreases Thursday. As a result, we`ve generally limited storm potential to our northern Cascades and across the more lightning prone areas of northern Klamath. As the trough moves over and then east of us Friday, conditions should stabilize, and we`ve kept the forecast dry for Friday. However, a trough moving through will probably bring gusty west winds, especially to east side locations. Thus, we lose one threat (lightning) and add another (wind) on Friday. Few changes were made to the extended forecast. A ridge moves in behind the trough this weekend and that will bring hotter, drier weather again. This also looks like a thermal trough setup which means offshore (northeast) winds and poor night time humidity recoveries in the coastal mountains. Models then show another upper low coming in early next week, but this one will probably be to our north, which is a dry, albeit cooler, weather pattern for our area. -Wright && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Red Flag Warning until 11 PM PDT Wednesday for ORZ617-623>625. Fire Weather Watch from 5 AM PDT Wednesday through Wednesday evening for ORZ617-621>623. CA...Fire Weather Watch from 5 AM PDT Wednesday through Wednesday evening for CAZ280-281. Red Flag Warning until 11 PM PDT Wednesday for CAZ284-285. Pacific Coastal Waters...None. $$
Area Forecast Discussion
National Weather Service San Francisco Bay Area
855 PM PDT Tue Aug 14 2018 .SYNOPSIS...Temperatures will remain near to slightly below seasonal averages through Wednesday with widespread night/morning low clouds. High pressure will build toward the West Coast by late week and result in a gradual warming trend, especially over the interior. && of 8:54 PM PDT Tuesday...A relatively deep marine layer, currently between 1800-2000 feet per the Fort Ord Profiler and a moderate onshore gradient maintained stratus coverage over portions of the coast and locally inland through the day today. As a result there was a mixed bag of temperatures this afternoon. Some areas that came in contact with the cool marine air and low clouds cooled while locations that were well inland or above the marine layer saw little to no change. Temperatures topped out in the upper 50s and 60s along the coast, 70s to 80s inland with a few 90s in the warmest interior valley locations. Another night of widespread stratus and patchy drizzle is anticipated tonight as the marine layer continues to deepen as a trough of low pressure situated off the west coast deepens. The forecast remains on track. No updates expected this evening. From previous discussion...The ridge of high pressure over the Desert Southwest will strengthen slightly and compress the marine later a bit by Wednesday afternoon. Thus, look for a slight warming trend for inland areas, especially across the East Bay and South Bay. Additional warming is likely for the interior late in the week as the ridge builds westward toward the California Coast. With warming 850mb temperatures, the interior will likely see afternoon highs back above seasonal averages with seasonable conditions near the coast. Little change is forecast into the upcoming weekend and early next week as the weather pattern remains dominated by the mid/upper level ridge. Thus, near to above normal temperatures inland with mostly sunny conditions each afternoon. Coastal areas will be closer to seasonal averages with periods of night/morning low clouds and patchy fog as a result of the marine layer and onshore flow. && of 04:36 PM PDT Tuesday...for 00Z TAFs. Stratus remains along much of the coast and over the Monterey Peninsula as the marine layer sits at around 2000 ft. Areas not currently experiencing BKN to OVC conditions can expect to see a return of low clouds by early this evening. MVFR/IFR cigs should move inland and down the valleys again this evening and overnight for all sites. Another round of late clearing can be expected tomorrow. Confidence is low on clearing time. No major smoke concerns as the latest HRRR shows less vertically integrated smoke over the Bay Area tonight and tomorrow morning. Breezy onshore winds will subside again tonight and tomorrow morning before increasing again in the afternoon, especially at KSFO. Vicinity of KSFO...MVFR cigs expected to continue this afternoon and evening before lowering to IFR tonight. Confidence on clearing time tomorrow is low, but expecting SFO to be under BKN- OVC skies through at least 21z. Winds will reduce this evening and overnight before onshore winds pick up again tomorrow afternoon. SFO Bridge Approach...Similar to the terminal. Monterey Bay Terminals...KMRY should remain under MVFR cigs the rest of the afternoon and evening before lowering to IFR for the night. Another early return of stratus is forecast for KSNS. It is possible that once again KMRY could remain under BKN-OVC conditions all day tomorrow with cigs raising to MVFR late tomorrow morning. Generally light winds through the period. && of 8:45 PM PDT Tuesday...Generally light to moderate northwest winds will continue across the coastal waters tonight and tomorrow with locally gusty winds along the Big Sur Coast south of Point Sur. Northwest swell will remain mild while the southerly swell will gradually increase throughout the week. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tngt...SCA...SF Bay until 9 PM SCA...Mry Bay until 9 PM SCA...Pigeon Pt to Pt Pinos 0-10 nm until 9 PM SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm && $$ PUBLIC FORECAST: CW AVIATION/MARINE: AS Visit us at Follow us on Facebook, Twitter, and YouTube at:
Area Forecast Discussion
National Weather Service New York NY
955 PM EDT Tue Aug 14 2018 .SYNOPSIS... Low pressure will pass to the north through tonight, followed by weak high pressure on Thursday. A warm front will then approach and lift through early Friday, followed by a cool front Friday night into Saturday. The front will then settle just offshore this weekend as weak low pressure rides along it. High pressure will briefly return on Monday before another frontal system approaches from the Plains states. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Shower activity is at a minimum right now, so only slight chance for the entire area until 10-11 pm when western sections of the area will start to see a chance for showers from an approaching area of showers moving in from northeaster Pennsylvania and souther New York. The HRRR seemed to have a good handle on it, so POPs are largely from that model. Otherwise, forecast is on track. The low pressure system progresses northeastward overnight. Showers will diminish gradually tonight and thunderstorms will be isolated and over the ocean where more instability will be located. Instability is expected to decrease through the night with upper level trough axis moving through and best lift area shifting southeast of Long Island. Breaks in the clouds overnight could lead to areas of fog with generally light winds and plentiful moisture as temperatures fall into the mid 60s north and west to low 70s across Long Island, NYC and along the coast. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/... Models continue to be in good agreement with the 500mb low will push east of the forecast area Wednesday. Drier air will continue to filter in behind this system as dewpoints will be dropping into the 60s. With high pressure ridging Wednesday into Wednesday night, expect mostly clear to partly cloudy skies. Forecast 850mb temps of 16C-17C combined with a westerly flow will result in max temps in the upper 80s to low 90s across most spots. With the lower dewpoints, expect heat indices just a degree or two higher than the actual temperature. Isolated 95 degree heat index values could occur in the city and immediate surrounding suburbs, but not enough coverage for heat advisory consideration. Ridging aloft will begin to break down Thursday with max temperatures a degree or two warmer. This could result in heat indices of low to mid 90s in and around the city. Minimum temperatures will remain in the low to mid 70s for most areas outside of northwestern counties. There is a moderate risk of rip current development at the ocean beaches on Wednesday. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... The ridge aloft will continue to break down and push offshore Thursday night in response to a shortwave advancing across the Great Lakes. As the associated surface low tracks across the lakes on Friday, a warm front will lift north of the region early in the day, followed by a cold frontal passage late Friday night into Saturday morning. Shower and thunderstorm chances will increase through the day, with heavy rain possible at times as precipitable water values again increase to around 2 inches. The front then settles just offshore during the day on Saturday. With energy lingering in the upper trough, this will result in at least the potential for unsettled weather to continue through the weekend. In addition, there are some indications that a shortwave over the Midwest develops a surface reflection as it emerges off the Mid Atlantic coast during the day on Sunday. At this point it appears that the bulk of the precipitation would remain south of the region late Sunday into Monday as that low rides northeastward along the old frontal boundary. Ridging then briefly builds back into the region during the day on Monday ahead of the next frontal system tracking eastward from the Plains. Temperatures on Friday and Saturday will continue to run several degrees above normal before falling back to near normal for the remainder of the long term period. With highs in the upper 80s to around 90 across much of the region on Friday and plenty of humidity, heat indices could rise into the mid to upper 90s across much of northeast New Jersey, New York City, and Long Island. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... An upper level low will pass to the north tonight. Weak high pressure will then build in on Wednesday. VFR for the TAF period, with just a few evening showers left over from daytime convection. S-SW winds mainly less than 10 kt should shift W-WNW overnight, then increase to around 10 kt with gusts 15-20 kt late morning and afternoon. Coastal sites should see at least some partial sea breeze influence, with winds either backing entirely to 240-250 true or fluctuating between 240-290 true. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component fcsts, can be found at: http:/ KJFK TAF Comments: Wind direction Wed afternoon could fluctuate between 240-290 true. KLGA TAF Comments: No unscheduled AMD expected. KEWR TAF Comments: No unscheduled AMD expected. KTEB TAF Comments: No unscheduled AMD expected. KHPN TAF Comments: No unscheduled AMD. KISP TAF Comments: Wind direction late Wed afternoon could fluctuate between 240-290 true. .OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY... .Wednesday night-Thursday...Mainly VFR. .Friday...MVFR or lower conditions possible in late day/evening showers/tstms from the NYC metros north/west. .Saturday and Sunday...VFR or lower conditions possible in showers and thunderstorms. && .MARINE... A brief period of increasing SW flow into early Wednesday could build ocean seas close to 5 ft farther offshore. Gusts should remain under 25 kt. Weak high pressure builds Wednesday night through Thursday night with relatively tranquil winds and seas. Southerly winds increase Friday night ahead of low pressure and a cold front. At this time, winds and seas are expected to remain below SCA thresholds. && .HYDROLOGY... Showers will taper tonight as low pressure shifts east. Dry conditions on Wednesday and Thursday will allow a bit of a reprieve, but an approaching frontal system could produce showers/tstms with heavy rain Friday afternoon and evening. Deep layer SW flow nearly parallel to the approaching frontal boundary will increase moisture over the region with PW expected to reach over 2 inches. There is potential for heavy rain with individual cells and also training of cells, mainly from the NYC metro area north/west. && .TIDES/COASTAL FLOODING... A coastal flood statement continues for tidal locations along southern Nassau and southern Queens, along the south shore back bays. Expect astronomical high tide levels will near minor flooding tonight. && .EQUIPMENT... NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) remains off the air for an extended period of time. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...FEB/99 NEAR TERM...JM/JP/99 SHORT TERM...99 LONG TERM...FEB AVIATION...Goodman MARINE...FEB/99 HYDROLOGY...FEB/99 TIDES/COASTAL FLOODING... EQUIPMENT...
Area Forecast Discussion
National Weather Service Mount Holly NJ
944 PM EDT Tue Aug 14 2018 .SYNOPSIS... The large low pressure system that has been responsible for the heavy rain in the area the last few days will continue to slowly lift northeast overnight away from the region. This will be followed by weak high pressure tomorrow. By Friday, another low crossing from the Great Lakes region into New England will bring a cold front into our region. This front is expected to stall over our region for much of the weekend before shifting southeast Sunday night or Monday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 930 pm update: Main adjustments to the forecast were modifying evolution of decreasing PoPs across the area. The biggest change was to areas near/north of I-80, where a batch of rain and embedded thunder was moving in from northeast Pennsylvania. Hi- res models have handled this poorly this evening, but the latest HRRR seems to suggest it diminishing gradually through or just after midnight. The precipitation has caused flash flooding in south-central New York and adjacent far northeast Pennsylvania. Current expectations are that the precipitation will diminish sufficiently so that the flash flood threat is low in our CWA. Nevertheless, given the antecedent very wet conditions across the area, cannot rule out a localized flooding problem with this precipitation, especially if it maintains intensity longer than progged. Previous discussion... A clear spin in the atmosphere was evident this afternoon on regional mosaic radar and GOES-16 satellite loops in association with a closed upper low over the Catskills region in upstate NY. This places our region under the dry slot and in westerly flow to the south of the cyclone. However, this dry slot is not very dry as the plume of tropical moisture that was drawn poleward ahead of this system has wrapped around the low, resulting in PWATs that are near or slightly above climo (1.5-1.75"). Sufficient moisture and diurnal instability combined with several sources of lift, has lead to another episode of showers and storms this afternoon. Convection was loosely organized earlier this afternoon but has since organized a bit into at least three broken line segments: (1) along a pre-frontal surface trough that was over the I-95 corridor at the moment and (2)/(3) a trailing shortwave troughs located over north-central and eastern PA. This means several rounds of showers and storms will affect eastern PA and NJ through the remainder of the afternoon and into the evening. The bulk of this activity this afternoon may pass to the north of Delmarva but the trailing convection could advance farther south into these southern zones this evening. Heavy downpours with these showers and storms are producing a quick one- to three-quarters of an inch but a steady storm motion (east at 10-20 mph) has limited the duration of the heavy rain and the threat of flash flooding. Nonetheless, poor drainage flooding is still a possibility for locations that see multiple rounds of brief heavy downpours and are particular flood prone due to the recent heavy rainfall. Under the assumption that storms don`t organize along a more west-east line (parallel to storm motion and favorable to training), the risk for flash flooding will be low. Showers and storms will diminish in coverage and intensity after sunset, but an isolated shower is still possible early into the overnight. A light west wind and cloud cover should limit the development of fog (in terms of coverage and density). However, patchy fog cannot be ruled out in the rural valleys if cloud breaks do develop. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... The upper trough will move off the New England coast while the attendant cold front progresses farther off the Mid-Atlantic coast. An upper shortwave ridge initially positioned west of the Appalachian spine in the morning will build eastward toward the area through the day. The aformentioned ridge may be far enough upstream of our area to guarantee one of those fleeting days without any showers or storms. The possibility for a weak shortwave disturbance riding atop of the ridge, development of a pressure trough and terrain circulations could provide a source(s) of lift for convective initiation during peak heating hours, mainly across the higher terrain and northern tier of the CWA (I-78 north). Coverage (PoPs) are forecast to be highest late in the afternoon but limited to low chance (30 percent) across the southern Poconos and isolated (20 percent) elsewhere N/W of the fall line and Mason-Dixon line. WAA in wake of the exiting trough in addition to strong daytime heating and downsloping flow will all contribute to a warming trend compared to recent days. Highs in the lower 90s are forecast for the urban I-95 corridor and coastal plain with upper 80s more common farther inland in the higher terrain. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... Summary...Relative calm Wednesday night and Thursday will be short lived as another low pressure system will bring more chances for rain Friday through the weekend. We may have another period of tranquil weather on Monday, before a stronger cold front could bring another round of storms Tuesday or later. Details: Wednesday night and Thursday...A mid level ridge is expected to progress east through this period, although it will be weakening as it does so. Therefore, the period should be starting out mostly dry, though some showers and storms could encroach on region from the west on Thursday as the next low begins to develop. With Thursday starting off mostly sunny, and dew points expected to remain in the lower 70s, we will see hot and muggy conditions during the day Thursday. Current forecast has conditions below heat advisory criteria, but will continue to monitor this as we get closer. Friday through Sunday...Developing low over the Great Lakes region will progress towards New England through the weekend. This low will bring a cold front into our region on Friday. However, it still looks likely that this front will stall over our region for much of the rest of the weekend. Consequently, expect continued chances for showers and storms through the weekend, especially on Friday and Friday night. However, thankfully, it looks like we should have faster storm motions limiting the flooding threat, although precipitable water values remain quite high. Temperatures through this period will be very dependent on where the front eventually stalls. Especially on Friday, we could see a large temperature gradient across our region with the coastal plains once again in the lower 90s (heat index values near 100), while the southern Poconos may struggle to reach 80. Monday...Mid and upper level short wave ridge is expected to quickly propagate east over our region resulting in a mostly dry day. Tuesday and beyond...This will be a period worth watching as almost all of the operational models are depicting a stronger cold front approaching our region from the west. There remain some major timing differences (the GFS doesn`t depict this front coming through at all through the first half of the week, while the ECMWF has it through the region Tuesday night), but if this pattern continues, this could finally bring in much drier air (after a period of showers and storms along and just ahead of the front). && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...Generally VFR, though some patchy fog cannot be ruled out at the terminals late tonight. For now, confidence is too low for inclusion in the TAFs. Additionally, watching precipitation to the northwest of KABE closely. Currently, think the best chances are north of the terminal, but may need to include some precip and at least temporary lower CIGs/VSBYs should this persist longer and progress farther southwest than anticipated. Any lingering precipitation should diminish after midnight. Light west winds. Low confidence. Wednesday...VFR with west winds 5 to 15 kts, perhaps with a few gusts to 20 kts or so. Moderate confidence. Outlook... Wednesday night...VFR conditions expected with light westerly winds. Patchy fog may develop near more rural TAF sites, but chance for this occuring is low. High confidence on the rest of the forecast elements. Thursday through Sunday...Predominantly VFR with temporary visibility and ceiling restrictions if any showers and thunderstorms affect a TAF site. The highest risk for this occuring is on Friday and Friday night. Southwesterly wind will be shifting to northerly and eventually northeasterly Saturday night into Sunday as a cold front sinks south. && .MARINE... W-SW winds 10-15 kt with gusts to 20 kt are occurring this afternoon in the DE Bay and coastal Atlantic waters. Meanwhile seas around around 4 ft in the coastal waters. Expect these conditions to continue into this evening except for a wind shift to W or even W-NW will occur behind a front around or shortly after sunset. A pressure surge behind the front could also yield gusts near 25 kt (SCA criteria) but it should only last for an hour or two per model forecast soundings. Accordingly a SCA was not issued. Isolated to scattered storms over land should reach the NJ waters late this afternoon. Isolated gusts at or above 30 kt are possible and could necessitate Special Marine Warnings. Another broken line of storms even farther inland may reach the waters closer to sunset but it is uncertain if the intensity will hold together by the time it reaches the coastal waters. W winds 10-15 with gusts to 20 kt are expected on Wednesday. Outlook... Thursday...Winds and seas should stay below SCA criteria. Friday...Southerly winds on the Atlantic waters will be increasing and could gust above 20 KT at times. Seas will subsequently increase as well. However, at this time it looks likely that both winds and seas will stay just below SCA criteria. Saturday and Sunday...Winds will gradually shift to westerly and then abruptly shift to northerly and northeasterly Saturday night into Sunday. behind this cold front, wind gusts to 25 kt and seas approaching 5 feet are possible. Rip Currents... A low risk for the development of dangerous rip currents is expected for the remainder of this afternoon and Wednesday as the flow remains offshore. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && $$ Synopsis...Johnson Near Term...CMS/Klein Short Term...Klein Long Term...Johnson Aviation...CMS/Johnson Marine...Johnson/Klein
Area Forecast Discussion
National Weather Service Pueblo CO
329 PM MDT Tue Aug 14 2018 .SHORT TERM...(This evening through Wednesday) Issued at 329 PM MDT Tue Aug 14 2018 Currently... Scattered showers and -TSRA were noted at 2 pm, mainly along and just east of the contdvd. More isold storms were just north of Teller county. Flow aloft has transitioned to northwesterly, and storms were moving southeast. Weak effective shear was noted (~25kts) and CAPE was running about 500-1000 J/KG. Over the lower elevation`s, skies were mostly clear. Temps were in the U70s to L80s, with similar temps in the larger valleys. Rest of Today and into Tonight... Storms will continue to increase in coverage and intensity as they move southeast across the higher terrain and then onto to the Plains. Latest hi res guidance has been indicating storms may be a bit stronger as they move onto the lower elevations and may make it onto the plains for 10s of miles before dissipating generally west of the longitude of KLHX. I cant rule out a marginally severe storm but most of the activity will not be all that strong. Main concern will be the burn scar areas, and the potential for flash flooding. Lightning is always a concern with any thunderstorm. By mid to late evening activity is expected to end. HRRR is a bit more robust in keeping storms going (especially up in the Pikes Peak area), but I think this may be a bit overdone. The predawn hours should be mostly clear, with min temps falling into the U50s to around 60F plains, 40s and 50s valleys and 30s mtns. Wednesday... Could see some marginally severe storms tomorrow. Better chance of strong convection tomorrow as a fairly decent jet streak comes across the area associated with a shortwave dropping southeast in the NW flow aloft. CAPE values should range to about 1000-1500 j/kg and shear of 30-35 knots should allow for some rotating convection capable of producing some hail up to silver dollars and wind gusts to 60 mph. Most favorable conditions will be just east of the interstate extending out towards the border. Over the far eastern plains CAPE starts to rapidly drop off, so storms may weaken as they approach the KS border. Burn scar flooding cant be ruled out tomorrow but CAPE values may be lacking across the higher terrain to promote heavy rainfall. Otherwise, expect another warm day across the region with mostly L90s across th plains with 80s in the greater COS region and in the valleys. .LONG TERM...(Wednesday night through Tuesday) Issued at 329 PM MDT Tue Aug 14 2018 Thursday appears to be another active meteorological day(in the form of some stronger storms as well as storms with heavy rain potential) across the majority of the forecast district(especially from mid-afternoon into the evening) as above average atmospheric moisture(per PW analysis near 1.20 across portions of the I-25 corridor) interacts with a subtle upper disturbance(per PV analysis) and a northeasterly to easterly surface surge. Friday has the potential to be somewhat less active over eastern portions while western locations should continue to experience scattered shower and thunderstorm activity. It still appears that this weekend has the highest potential of experiencing more widespread and potentially intense storm activity as unseasonably strong upper disturbance(per PV/jet analysis) and northerly surface surge impacts the forecast district. For example, over eastern locations, projected localized capes, LI`s and deep-layer shear values exceeding 1500 J/KG, -6C and 45 knots respectively are anticipated at times from Saturday afternoon into Saturday night. Then, will continue with theme of primarily afternoon into evening shower and thunderstorm activity(generally favoring higher terrain locations) Monday and to a lesser degree Tuesday as strong upper ridge develops near the 4-corners region by Tuesday night. Finally, near to above seasonal mid-August maximum temperatures are projected to continue over the forecast district from Thursday into Saturday, with below seasonal temperatures then anticipated from Sunday into next Tuesday. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 329 PM MDT Tue Aug 14 2018 A passing thunderstorm cant be ruled out at each of the TAF sites later this afternoon/early evening and tomorrow afternoon/early evening. Best chance of storms will be over KCOS with lesser chances over KALS and KPUB. Otherwise expect VFR conditions and generally light winds (expect vcnty TSRA). && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
Area Forecast Discussion...UPDATED
National Weather Service Shreveport LA
939 PM CDT Tue Aug 14 2018 .UPDATE... Strong to severe thunderstorms persist across Central Oklahoma. Most of the models seem to have initialized poorly (wrong location of ongoing storms) or exhibit easterly storm motions versus southeasterly, which is what is being observed on radar. Among the various guidance, the HRRR appears to be the only one even close to the current situation. Even though latest radar loops appear to show some weakening along the leading edge of the storms, they also appear to be congealing into more of a solid complex. Latest mesoanalysis also suggests there is enough instability across Southern Oklahoma to maintain the convection for several more hours, but a gradual weakening trend is expected. Long story short, there is still a chance for storms to affect Southeast Oklahoma and adjacent portions of extreme Southwest Arkansas and Northeast Texas after midnight. Therefore, current PoPs will be maintained. Overall, the vast majority of the forecast was kept intact. Minor updates were made to some of the hourly grids based on observed trends. CN && .PREV DISCUSSION... /issued 701 PM CDT Tue Aug 14 2018/ AVIATION... For the 15/00z TAFs, abundant mid and high level cloud cover will persist for much of the overnight hours but should decrease in coverage somewhat during the night. Patchy stratus may lead to MVFR conditions across portions of East Texas and Western Louisiana for a few hours around sunrise Wednesday morning. This includes KSHV, KGGG, KTYR, and KLFK. Flight conditions should improve by mid to late morning, and VFR conditions should then prevail for the duration of the period. Southwesterly surface winds will also increase to between 10 and 15 kts in most locations after 15/12z. There may be some gusts near 20 kts at a few sites, particularly across East Texas. CN PREV DISCUSSION... /issued 426 PM CDT Tue Aug 14 2018/ SHORT TERM...Tonight through Wednesday Night/ Upper level low continues to lift northeastward across eastern KS into western MO with trailing convection southward to along the middle Red River Valley of northeast Texas, southeast Oklahoma and southwest Arkansas. These areas will continue to see scattered showers and a few embedded thunderstorms through the evening and overnight hours as large scale ascent continues along the trough axis with ejecting upper level low. Another shortwave trough on the back side of the upper low is also noted across south central KS and western OK, and this feature will shift farther southeast overnight with additional convection possibly reaching our far northern zones after midnight through early Wednesday morning. Scattered convection will remain possible through the day on Wednesday with this shortwave feature traversing the northern third of our region. Elsewhere, expect hot and humid conditions with high temperatures returning back to the mid 90s for highs on Wednesday afternoon. Overnight temperatures will begin to increase with lows in the mid to possibly upper 70s on Wednesday night as warm, moist southerly flow from the Gulf prevails. /19/ LONG TERM.../Thursday through Tuesday/ Closed upper level low pressure system over the central sections of the country tonight will continue lifting to the Northeast toward the Great Lakes Region as an open wave. The trailing trough axis will keep rain chances for the more Northern parts of the forecast area on Wednesday and the Eastern areas through Thursday. Another disturbance aloft in the Northwest flow be approaching the Four State Region Thursday night and by Friday providing scattered to numerous showers and thunderstorms. Additional weak disturbances will linger the rain chances for the area into the weekend with the Northeast periphery having the higher rain chances. In the first half of next week a significant upper trough will be moving into the upper ridge out west carving out a deeply amplified trough sending a cold front into the area by mid week with another round of significant rainfall and cooler temperatures. Daytime high temperatures will be warming well into the 90s in the rain free regions with upper 80s to lower 90s in rain areas and thicker cloud covered regions. /06/ && .PRELIMINARY POINT TEMPS/POPS... SHV 75 96 76 97 / 0 10 10 20 MLU 74 97 75 97 / 0 10 10 30 DEQ 72 91 74 93 / 20 30 30 30 TXK 74 93 76 94 / 20 20 20 20 ELD 74 95 76 95 / 10 10 20 30 TYR 75 94 77 96 / 10 10 10 10 GGG 75 95 76 96 / 10 10 10 10 LFK 74 95 75 96 / 0 10 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 09/13