Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/25/16


AREA FORECAST DISCUSSION
National Weather Service San Diego CA
936 AM PDT MON MAY 23 2016 .SYNOPSIS... A low pressure trough will continue to deepen over the west coast today. This feature will bring onshore flow, below normal inland temperatures, and a deep marine layer responsible for the night and morning low clouds. Light rain or drizzle is possible west of the mountains tonight into Tuesday morning, then again Tuesday night into Wednesday morning. On Wednesday, a weak low pressure disturbance will bring a slight chance of showers and thunderstorms to the inland valleys and mountains. A trough along the West coast will remain stagnant over the region through this weekend, maintaining the low clouds west of the mountains, onshore flow, and below normal temperatures. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... AT 8 AM PDT...Water vapor imagery showed broad troughing draped along the west coast with the center of low pressure located over northern California. The 12z KNKX sounding indicated the marine temperature inversion at 2600 ft msl with dry air aloft. Onshore surface pressure gradients have nearly doubled in strength as compared to 24-hours ago with SAN-TPH now +5.7 mb and SAN-DAG +5.4 mb. As the west coast trough deepens today, scattered low clouds will persist west of the mountains and breezy westerly winds will develop in the mountains and deserts. Temperatures along the coast are forecast around 5 degrees below normal with inland temperatures 10 to 15 degrees below normal for this time of year. Tonight, the local WRF model depicts the stratus marine layer deepening to around 4000 ft msl and generates patchy light rain or drizzle west of the mountains. Synoptically little changes on Tuesday. Breezy westerly winds will continue across the mountain tops and desert slopes with inland temperatures on the cool side, 10 to 20 degrees below normal. Tuesday night into Wednesday, both the 12Z GFS and 00Z ECMWF drop a distinct vort max southward towards Southern California. This feature will once again act to deepen the marine layer Tuesday night and maintain gusty westerly winds in the mountains and deserts. Patchy light rain or drizzle will again be a possibility west of the mountains. As the center of the low moves overhead on Wednesday, 500 mb temps lower to near -20 C. This cold and marginally unstable air aloft, combined with limited moisture, will generate a slight chance of showers and thunderstorms in the mountains and inland valleys through the afternoon. Temperatures on Wednesday will be well below normal, especially inland and over the mountains with a handful of mountain locations forecast 20-25 degrees below normal. A rather stagnant weather pattern holds in place through the end of the weekend and into early next as the west coast trough remains in place. So Cal residents can expect more night and morning low clouds west of the mountains, onshore flow, and below normal temperatures. && .AVIATION... 231515Z...Coast/Valleys...Areas of bkn low clouds based mainly 2000-3000 ft MSL with tops to near 3500 ft MSL. After about 23/19Z becoming mostly scattered. Confidence in conditions becoming scattered by afternoon today is high. After about 24/02Z this evening scattered clouds will become more broken into the night with bases mainly around 2000-3000 feet MSL and tops around 3500 ft MSL. Risk of bkn low clouds with bases below 2000 feet MSL at times tonight is moderate-high at KSAN. Mountains/Deserts...Lower coastal slopes below 3500 ft locally obscured before 23/18Z otherwise mostly clear. West winds with local gusts of 30-40 mph will produce weak to moderate up/down drafts over and east of the mountains through tonight. && .MARINE... 815 AM...Wind gusts near 20 knots at times through this evening over the outer waters. Otherwise, no hazardous marine weather is expected through Friday. && .SKYWARN... Skywarn activation will not be needed today. && .SGX Watches/Warnings/Advisories... CA...None. PZ...None. && $$ PUBLIC...JT AVIATION/MARINE...Small
Area Forecast Discussion National Weather Service Sacramento CA 915 AM PDT MON MAY 23 2016 .SYNOPSIS... An upper level disturbance will continue to bring unsettled weather and cool conditions across NorCal this week. && .Short Term Discussion... Forecast largely on track this morning. Latest hi-res guidance continues to indicate showers popping up over next several hours with coverage expanding into the afternoon. Showers will generally remain over higher elevations but cannot rule out a shower or two in the Valley. Modest instability will be present as shortwave moves across the area, so isolated thunderstorms are possible as well. Accumulations will generally be light although locally heavier amounts possible in any thunderstorm. Afternoon temperatures will top out in the low to mid 70s in the Valley with 40s-60s across higher elevations. CEO .Previous Discussion... Clear to partly cloudy skies across interior NorCal early this morning. Temperatures are pretty similar to readings from 24 hours ago and generally range from the 30s and 40s in the mountains to the upper 40s and 50s elsewhere. Long-wave trough will remain in place over the West through the period maintaining cool and unsettled weather for the region. Weak circulation evident on satellite imagery to the west of the Bay Area (37N/129W) is forecast to move toward central California today and may provide the trigger for another upswing in shower and thunderstorm activity by this afternoon. Most of the action is expected over the foothills and mountains, but the HRRR is indicating that some showers may develop in the Sacramento region (NE quad of the approaching low) around the afternoon commute time. Tuesday is expected to be quite similar to today as the weak low continues to hang out over central California. With cloud cover and a rather cool airmass remaining across the region, temperatures will remain below average. Less coverage of showers and thunderstorms are expected across NorCal on Wednesday and Thursday as the low shifts south and east of the area. Temperatures will gradually warm each day as the airmass modifies and most areas see more sunshine. && .EXTENDED DISCUSSION (Friday THROUGH Monday) The long term forecast period should begin dry for interior northern California as a shortwave ridge of high pressure begins to break down. High temperatures are looking to return to near normal into the lower to mid 80s the valley and the 50s and 60s for the higher elevations. Another upper level system is depicted in model forecasts to slide across the Pacific NW Friday night into Saturday, and a portion of the jet stream could clip northern California. As a result, there will be the possibility of some showers and isolated thunderstorms for northern portions of the Sierra and southern Cascades for next weekend. Any snow accumulations should remain confined to the upper elevations, which should not affect mountain pass travel. Model forecasts are in decent agreement as to the amplitude and general timing pattern of the upper level low for next weekend, however the progression differs slightly as to when the system will clear northern California. Although there are slight differences in the forecast scenarios, the beginning of next week should dry out as a ridge builds back into the west from the eastern Pacific. && .AVIATION... VFR conditions are expected for the terminals for the next 24 hours with light wind shifts. An upper level trough continues to linger over northern California, which will result in BKN to OVC ceilings for most flight times during the forecast period for the TAF sites. Showers and thunderstorms today should stay confined to higher elevations, although portions of the northern valley near KRDD and KRBL could also see some shower or thunderstorm activity. Confidence is low as to showers developing within the vicinity of the terminals, so left mention out of the TAF for now. && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
National Weather Service San Diego CA
345 AM PDT MON MAY 23 2016 .SYNOPSIS... A trough of low pressure over the western states will strengthen a little through Wednesday...then weaken again for next weekend. High temperatures will remain below average for inland areas through much of the week...then warm towards the end of the week into next weekend. A deep marine layer will bring areas of night and morning low clouds and patchy fog for coastal areas inland to the coastal mountain slopes. There are small chances for light precipitation along and west of the mountains for late tonight into Tuesday morning and again late Tuesday night into Wednesday morning with a slight chance of thunderstorms near the mountains Wednesday afternoon. There will continue to be periods of gusty west winds in the mountains and deserts...stronger during the late afternoon and evening each day. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Wednesday)... Broad low pressure extends across the western states. Within that broader low pressure...a shortwave off the California coast will move inland through Southern California tonight and Tuesday. This will bring deepening of the marine layer with a slight chance of light showers along and west of the coastal slopes of the mountains for late tonight into Tuesday morning. A second shortwave moving southward just off the West Coast will move inland through Southern California Tuesday night and Wednesday as a closed low pressure system. This will bring a slight chance of light showers along and west of the coastal slopes of the mountains late Tuesday night into Wednesday morning. With the coldest mid level air moving across Southern California Wednesday...there is a slight chance of thunderstorms Wednesday afternoon...mainly near the mountains and inland valleys. Inland high temperatures will cool slightly through Wednesday with gusty west winds in the mountains and deserts...strongest during the late afternoon and evening each day. && .LONG TERM (Thursday through Sunday)... The trough of low pressure will weaken for Thursday and Friday. A low pressure system moving into the Pacific Northwest on Saturday will maintain the low pressure trough into Southern California through the Memorial Day weekend. Areas of night and morning coastal low clouds and patchy fog will continue with slow warming of inland high temperatures. && .AVIATION... 230900Z...Coast/Valleys...Mostly scattered, but occasionally broken low clouds will continue through 18z. Cigs would be around 2500 feet msl with tops to 3200 feet. After 02z scattered clouds will become more broken overnight with bases around 2500 feet msl. Mountains/Deserts...West winds with local gusts of 30-40 mph will produce weak to moderate up/down drafts over and east of the mountains through tonight. Otherwise, mostly clear. && .MARINE... 200 AM...Wind gusts near 20 knots at times this evening over the outer waters. Otherwise, no hazardous marine weather is expected through Friday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX Watches/Warnings/Advisories... CA...None. PZ...None. && $$ PUBLIC...17 AVIATION/MARINE...MM
Area Forecast Discussion National Weather Service Sacramento CA 330 AM PDT MON MAY 23 2016 .SYNOPSIS An upper level disturbance will continue to bring unsettled weather and cool conditions across NorCal this week. && .SHORT TERM Clear to partly cloudy skies across interior NorCal early this morning. Temperatures are pretty similar to readings from 24 hours ago and generally range from the 30s and 40s in the mountains to the upper 40s and 50s elsewhere. Long-wave trough will remain in place over the West through the period maintaining cool and unsettled weather for the region. Weak circulation evident on satellite imagery to the west of the Bay Area (37N/129W) is forecast to move toward central California today and may provide the trigger for another upswing in shower and thunderstorm activity by this afternoon. Most of the action is expected over the foothills and mountains, but the HRRR is indicating that some showers may develop in the Sacramento region (NE quad of the approaching low) around the afternoon commute time. Tuesday is expected to be quite similar to today as the weak low continues to hang out over central California. With cloud cover and a rather cool airmass remaining across the region, temperatures will remain below average. Less coverage of showers and thunderstorms are expected across NorCal on Wednesday and Thursday as the low shifts south and east of the area. Temperatures will gradually warm each day as the airmass modifies and most areas see more sunshine. && .EXTENDED DISCUSSION (Friday THROUGH Monday) The long term forecast period should begin dry for interior northern California as a shortwave ridge of high pressure begins to break down. High temperatures are looking to return to near normal into the lower to mid 80s the valley and the 50s and 60s for the higher elevations. Another upper level system is depicted in model forecasts to slide across the Pacific NW Friday night into Saturday, and a portion of the jet stream could clip northern California. As a result, there will be the possibility of some showers and isolated thunderstorms for northern portions of the Sierra and southern Cascades for next weekend. Any snow accumulations should remain confined to the upper elevations, which should not affect mountain pass travel. Model forecasts are in decent agreement as to the amplitude and general timing pattern of the upper level low for next weekend, however the progression differs slightly as to when the system will clear northern California. Although there are slight differences in the forecast scenarios, the beginning of next week should dry out as a ridge builds back into the west from the eastern Pacific. && .AVIATION VFR conditions are expected for the terminals for the next 24 hours with light wind shifts. An upper level trough continues to linger over northern California, which will result in BKN to OVC ceilings for most flight times during the forecast period for the TAF sites. Showers and thunderstorms today should stay confined to higher elevations, although portions of the northern valley near KRDD and KRBL could also see some shower or thunderstorm activity. Confidence is low as to showers developing within the vicinity of the terminals, so left mention out of the TAF for now. && .STO Watches/Warnings/Advisories... None. && $$ Area Forecast Discussion National Weather Service New York NY 959 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure departs to the northeast as high pressure builds to the south on Wednesday. A cold front moves through on Thursday. High pressure will then dominate through Saturday night as a series of weak upper level disturbances move across. A cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. persistent showers continue to track down from new england...so have added chc pops for a few more hours as a weakening trend is noted on radar as well as in the hrrr. dry weather should return by midnight with decreasing clouds overnight. have also added patchy fog to ct coastal areas and ern long island overnight with light winds and high moisture content at the sfc. Otherwise...minor adjustments made to hourly t/td. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. With lighter winds across the interior, min temperatures were further lowered by a degree. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south overnight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light overnight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... light pcpn amounts (less than 1/10 inch) in any remaining showers this eve. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
  [top] Area Forecast Discussion National Weather Service Albany NY 812 PM EDT TUE MAY 24 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... As of 800 PM EDT...Weak deformation axis association with scattered to broken band of showers just east of the Hudson River should continue into the evening hours. The upper low in the vicinity of Providence, RI is beginning to show signs of tracking ENE per the latest H2O loop analysis. With this movement we should see a diminishing trend in the showers which too is suggested by the HRRR. So main update was to the sky coverage, PoPs/WX, removed the mention of thunder and expanded the fog a little further west to include the Hudson River Valley overnight as skies should clear overnight under diminishing winds. Question will be just how much fog impact will occur as dewpoints upstream were between 30-40F compared to mid 50s across eastern NY. We will monitor closely. Prev disc...Upper low departing northeast slowly but steadily. Very narrow band of rain in eastern NY with some isolated thunderstorms from the Berkshires through NW CT and the mid Hudson Valley. Rain and isolated thunderstorms will build east and dissipate through the evening...and clearing will take place through the night. Quite a bit of clearing outside of the moisture field of the upper low...so by daybreak most areas should be clear to mostly clear. There could be some patchy fog as low level winds should trend to calm and areas with wet ground could support some patchy fog but with dryer surface dewpoints advecting in...it could minimize chances for fog. Only including patchy fog for areas east of the Hudson Valley into western New England where most of the rain has fallen. Lows in the mid 40s to lower 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Showers continue to impact the Hudson River Valley and points east which is mainly where our TAFs are located. Included a VCSH or a TEMPO group for the next few hours. Otherwise, VFR conditions through the evening hours. The question for tonight will be how much BR/FG form. All terminals will clear out overnight. Winds will be light but dewpoints upstream are about 10-15 degrees cooler than those observed across eastern NY and western NE. At this time, the best IFR chances for FG are at KPSF/KGFL where showers and trapped moisture near the inversion. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS www.weather.gov/albany
Area Forecast Discussion National Weather Service New York NY 737 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. High pressure will dominate through Saturday night as a series of weak upper level disturbances move across. A back door cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. Made some adjustments to pops next couple of hours based on latest radar trends. Showers continue to weaken this eve and dry weather should return by midnight. Otherwise...minor adjustments made to hourly t/td and winds. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. Also with lighter winds across the interior and residual low level moisture...there could be some patchy fog late into early Wednesday Morning. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /23Z TUESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south tonight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light tonight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: No unscheduled amendments this evening. A late day seabreeze is expected Wednesday. KLGA TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KEWR TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KTEB TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KHPN TAF Comments: Patchy fog is possible overnight. West winds will increase by afternoon with occasional gusts expected. KISP TAF Comments: No unscheduled amendments this evening. A late day seabreeze may approach the airport Wednesday, but do not expect the seabreeze to move through at this time. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected into early this evening. Locally higher amounts will be possible in thunderstorms. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
  [top] Area Forecast Discussion National Weather Service Taunton MA 703 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers will continue across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 700 PM Update... Overall forecast is on track. Removed the thunder mention for this evening as convection has remained just west of southern New England. Also increased precip trends across RI and southeast MA as area of showers continues to develop and spin as the upper level low begins to slowly shift eastward. Otherwise breaks of sun across western MA as allowed for temps to warm in to the upper 60s late this afternoon. Onshore flow across eastern MA will continue until the low shifts eastward creating more of a northerly flow. Fog and drizzle will remain over the next several hours. May need to watch for radiational fog development tonight across the low lying areas as lingering low level moisture combined with cooling temperatures will create a low temp/dewpoint spread. Dense fog is not expected at this time. Previous Discussion... An area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Isolated lighter showers east of the Worcester Hills tonight. Mainly MVFR all terminals except Coastal MA which will see periods of IFR. VFR across the CT valley. Cigs and vsby improve from west to east after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...Nocera/Dunten SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Nocera/Dunten MARINE...Nocera/Dunten FIRE WEATHER...
Area Forecast Discussion National Weather Service Taunton MA 411 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers and isolated embedded thunderstorms over Western portions of MA and CT will continue into early this evening. Scattered showers may also develop across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 400 PM Update ... Vertically stacked low over the region with -19c air at 500 mb. This cold air aloft combined with cyclonic flow is resulting in scattered showers and embedded thunder. The convection is focused on the western side of the low where SPC mesoanalysis indicates some baroclinicity at 850 mb and 925 mb along with some breaks of sunshine yielding 250-500 j/kg of SB cape per mesoanalysis. This will continue to be the theme thru sunset with convection focused across this region. A second area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Highlights... * Very warm Wed/Thu/Fri with highs well up into the 80s except cooler immediate coast at times * Hot Saturday afternoon w/highs mainly upper 80s to the lower 90s * A few showers/t-storms possible Thu night/Fri but best chance Sat afternoon/evening ahead of cold front * Turning much cooler Sun and especially Mon along the coast Details... Wednesday night...Other than a low risk for a spot shower/t-storm across the interior during the evening dry weather is expected behind a weak cold front. Low temps will only fall back into the 50s in most locations with 60 to 65 in some of the urban centers. A touch of patchy fog may develop in the typically prone locations toward daybreak. Thursday...Upper level ridging across the Southeast U.S. continues to nose into southern New England. This will result in plenty of sunshine and with warm mid level temps, highs again should reach well into the 80s in most locations. However, gradient will be weaker allowing for sea breezes to develop on the immediate Eastern MA coast including Boston by early afternoon. High temps will still likely reach well up into the 70s to near 80 in this region before sea breezes develop and temps fall a bit. Should remain dry given lack of forcing and upper level ridging nosing into this region. Thursday night and Friday...A shortwave will lift northeast into northern New England Thu night/Fri. While the best forcing will to our north, a few showers/t-storms are possible with the best chance across western and northern MA. Certainly not expecting a washout though and the majority of the Thu night/Fri will be dry. Still looks like a warm afternoon with temps into the 80s, but it may be cooler across Northeast MA depending on location of backdoor cold front. Saturday...A hot day with westerly flow and 850T near 16c. This should yield highs in the upper 80s to lower 90s for most locations. Dewpoints into the 60s will make it feel somewhat muggy. Pre-frontal trough ahead of an approaching cold front may trigger scattered showers/thunderstorms mainly Saturday afternoon and evening. Sunday and Monday...High pressure over the Canadian Maritimes will build south into New England. So despite rather high height fields, northeast low level flow will result in much cooler temps Sun and especially Mon particularly along the coast. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Some improvement in vsbys observed over past 1 to 2 hours but cigs slow to rise in onshore flow across much of the area. Believe will begin to rise into the VFR range across the CT River Valley by mid afternoon. Rest of the area should see very slow improvement into at least low MVFR cig range, although there could be a few holdouts below one thousand feet in SE coastal areas. Scattered showers and even isolated thunderstorm or two could develop late this afternoon/evening over portions of RI and SE MA. There could also be scattered showers/isolated thunderstorms that develop during the late afternoon near the Berkshire Crest. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Showers with isolated thunder focused across Western portions of MA and CT. Isolated lighter showers elsewhere. Mainly MVFR all terminals except Coastal MA. Showers dissipate with sunset and cigs and vsby improve after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Showers should stay west of BDL airspace but will be close and need to watch early this evening. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR conditions other than a few hours of patchy ground fog possible toward daybreak Thu in the typically prone locations. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period with the exception being Wednesday night. Some brief near shore southwest wind gusts of 20 to 25 knots are likely Wed afternoon...which will result in some choppy seas. In addition, long southwest fetch may bring a period of 5 foot seas across our southern waters Wednesday night which may require headlines. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera NEAR TERM...Nocera SHORT TERM...Nocera LONG TERM...Frank AVIATION...Frank/Nocera MARINE...Frank/Nocera FIRE WEATHER...Nocera
Area Forecast Discussion National Weather Service New York NY 248 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. This lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... Higher vorticity advection associated with residual cold pool aloft with lingering upper level low combined with increased daytime heating has led to scattered showers and thunderstorms. Some gusty winds and small hail as well as heavy rain are possible for brief periods of time with these thunderstorms. Most of the convection has been confined to Southwest Connecticut and Western Long Island Sound. With CAPE values forecast of a few hundred J/KG more showers and thunderstorms will be possible with coverage being scattered. This will decrease with loss of diurnal heating and as cold pool aloft shift farther east this evening. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... For tonight, the region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest into early this evening. Locally higher amounts will be possible in thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/JP NEAR TERM...JM SHORT TERM...JM LONG TERM...JP AVIATION...MPS MARINE...JM/JP HYDROLOGY...JM/JP
Area Forecast Discussion National Weather Service New York NY 150 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast today and tonight, moving along the New England coast. High pressure builds in briefly for late tonight and Wednesday. A cold front moves through late Wednesday night into Thursday morning and lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... The forecast is pretty much on track here. There were some slight adjustments to better match observed trends with regards to temperatures, dewpoints, and pops for showers. Otherwise though, no remarkable changes were made to the forecast database. A weakening low south of Cape Cod tracks slowly northeast through today. A weak surface trough extends back from the low into the lower Hudson Valley. Meanwhile an upper closed, and nearly cutoff low, east southeast of the Delmarva, as seen on the water vapor loop, drifts north to northeast and begins to fill and get picked up by the northern stream. With areas of energy rotating around the low and the surface low, showers will continue through this morning, eventually becoming more scattered this afternoon. Instability is very weak this morning and generally less than 50 J/KG but this will increase this afternoon to a few hundred J/KG with increased daytime heating at the surface. Forecast includes isolated thunderstorms this afternoon. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Tonight the upper low continues to fill and becomes an open wave after 06Z and the northern stream carries the low into Maine and Nova Scotia, merging with low pressure over eastern Canada. The surface low becomes nearly indistinguishable by late tonight, also merging with a surface low over eastern Canada. By 00Z precipitation is quickly ending as heights rise from as weak upper ridging builds to the west. This ridge builds through Wednesday with dry weather late this evening through Wednesday. Warmer air continues to move into the region tonight through Wednesday at the lower and mid levels. A dramatic warmup is expected across the entire region as a westerly flow allows even coastal areas to warm to well above seasonal normals. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http://www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday as a weakening low south of Cape Cod tracks to the northeast through tonight and high pressure builds in late tonight and Wednesday. The only hazard across the forecast waters will be isolated thunderstorms this afternoon into early this evening. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest of today into this evening. Locally higher amounts will be possible in isolated thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP/MET NEAR TERM...JM/MET SHORT TERM...MET LONG TERM...JP AVIATION...MPS MARINE...JM/JP/MET HYDROLOGY...JP/MET
Area Forecast Discussion National Weather Service Albany NY 147 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure over southeast Long Island will bring scattered to numerous showers across our region from the Capital District south and east today with perhaps a rumble of afternoon thunder. Clouds will keep temperatures a little less warm than yesterday. This storm will move to our east tonight and high pressure will briefly build in through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 134 PM EDT...A closed off upper level low is located just southeast of the region off the coast of southern New England to the east of Long Island. Moisture wrapping around this feature continues to allow for some showers. The bulk of these have been occurring over southern Vermont and into adjacent Washington and Rensselaer Counties New York. Some parts of southern Vermont have seen locally around an inch of rainfall according to the latest MRMS precip estimation. Temps continue to vary from northwest to southeast across the area this afternoon. Thanks to partly to mostly sunny skies, some parts of the central/western Adirondacks have already reached into the mid 70s, while southern and eastern areas seeing lots of clouds remain only in the low 60s. Temps look to be fairly steady for the afternoon hours, with the warmest readings in northwest parts of the area. Most places from Albany on south/east won`t see much sun for the remainder of the day. The latest 16z 3km HRRR suggests that the threat for showers will remain in the forecast for this afternoon, mainly for areas east of the Hudson River. There might be enough instability with colder temperatures aloft for an isolated thunderstorm this afternoon, although most areas won`t see any thunder. Will continue with just a slight chance of thunder for much of the area. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... The cutoff low is forecast to drift east of Cape Cod tonight taking all the showers with it. Weak high pressure will build tonight into early Wednesday with a return to sunshine and higher temperatures back to 80-85 in the valleys, mid to upper 70s over the higher elevations. By afternoon, a weak back door front looks to slip southward into the Adirondacks touching off some scattered showers and possibly thunderstorms. One or two cells could make it south into the Capital region and even northern Catskills. A west to southwest wind 5-15 mph will become northwesterly during the afternoon. The front looks to washout by Wednesday night over the region as it slides to our south. Wednesday night looks dry with perhaps a little patchy fog as the wind will become light or calm overnight. Thursday will start out dry, but with increasing moisture, and perhaps a weak short wave, some scattered showers or thunderstorms could develop by afternoon across the region. These will be hit and miss with many areas likely not getting any rain at all. Otherwise, temperatures will climb in the mid or upper 80s in the valleys, 75-80 higher terrain. Dewpoints will reach the lower 60s in the Hudson valley south of Albany, mid or upper 50s further north so it will feel a little uncomfortably warm to some. && .LONG TERM /FRIDAY THROUGH MONDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. Friday-Friday night...the warm front finally moves through eastern NY and western New England during this time frame. A warm and humid air mass settles in...as dewpoints rise into the 60s. The boundary will likely be in the vicinity of the forecast area...and a weak short-wave in the west to southwest flow aloft will likely focus isolated to scattered showers and thunderstorms. The latest GFS20 has modest SBCAPEs in the 1000-2000 J/kg range, but the amount of deep shear remains uncertain. It is hard to ascertain if the convection will be severe this far out. H850 temps rise to +14C to +16C with highs in the lower to mid 80s in the valley locations...and mid 70s to around 80F over the mountains. The showers and thunderstorms should diminish quickly with the boundary retreating northward and the daytime heating gone. Lows will be upper 50s to lower 60s over most of the forecast area. Saturday-Saturday Night...The subtropical high builds in from the western Atlantic. The ALY forecast get into a warm sector. H850 temps nudge up to +15C to +17C on the latest ECMWF. PWATs increase to 1-1.5 inches. The GFS model soundings do not look very capped. Pop-up diurnally-driven showers and thunderstorms will be possible capable of heavy rainfall. The big question is the timing of the backdoor cold front from Northern New England and southeast Canada. The guidance varies on the timing and placement of the boundary. Our forecast reflects a timing more Saturday night into Sunday. Highs will be steamy for late May with humidity levels on the increase. Highs will be mainly in the mid and upper 80s for elevations at 1000 ft or lower...and upper 70s to lower 80s over the mountains. A slight to low chc of showers and thunderstorms will likely linger most of the night as the backdoor cold front dips south/southwest across the region. Sunday into Memorial Day...Temps look a bit cooler...closer to normal for late May on Sunday...as the backdoor cold front stalls over central NY...eastern PA and northern NJ. The ECMWF has H850 temps fall back to +10C to +12C from east to west over the forecast area...as the cold front moves through...and high pressure builds in from New Brunswick and Nova Scotia. There will continue to be solid chances of showers and thunderstorms as the cold front looks to move through. The amount of instability available will be the main issue for any strong to severe thunderstorms as the shear increases. This will continue to be monitored over the next several days. Highs on Sunday fall back into the mid 70s to lower 80s. Lows Sunday night fall back into the 50s to lower 60s. Memorial Day will feature a threat of a shower or thunderstorm...but it is uncertain where the frontal boundary goes. The latest WPC guidance has it move north into southern Quebec and Northern New England again. When a boundary is in the area with light to moderate amounts of instability and appreciable moisture...then a slight to low chc of showers and thunderstorms...especially in the afternoon will persist through the holiday weekend. Overall...it does not look like a washout at this point. After lows Sunday night in the 50s...highs will likely be in the 70s. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Still some spokes of precipitation rotating around the low pressure system to our east. Have VCSH at all terminals for the afternoon. Not out of the question that a terminal could drop to MVFR conditions in a shower...or perhaps IFR...but chances are slight. Slight chances for TSRA this afternoon as well...but not sufficient to warrant mention in TAFs. So will maintain VFR at all terminals this afternoon. Question for tonight will be how much BR/FG form. All terminals will clear out tonight. Winds will be light. Best chances for FG are at KPSF where showers deposited around 0.2 inch of rain today. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday through 18z. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA...TSRA. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: Moderate Operational Impact. Chance of SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... RH levels should remain elevated today dropping not low than about 50 percent most places. There will be scattered to numerous showers mainly from the Capital region south and eastward. Most areas will likely not receive a quarter inch, except perhaps Litchfield county into the Mid Hudson valley and southern Catskills. The showers will move out tonight leaving us with a nearly fully recovery and likely the formation of dew as the wind will be light. Wednesday, will start out dry and sunny. A weak disturbance could trigger scattered showers and thunderstorms mainly north of the Capital region but a few could stray further south. A full recovery tonight as the showers move out followed by warm increasingly humid weather for the balance of the week. Low pressure tracking close to southern New England will scattered to numerous showers from the Capital region and perhaps an afternoon thunderstorm to locations from the Capital Region south and east. Weak high pressure will build east off the mid Atlantic states and summer like weather will spread across our region from the southwest through the end of next week. The surface wind will be light out of the north or northeast through Tuesday, generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms today. At this time amounts up to a tenth of an inch in our northwestern zones, to quarter to half an inch in our southeastern zones is anticipated. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...HWJIV NEAR TERM...Frugis/HWJIV/OKeefe SHORT TERM...HWJIV LONG TERM...Wasula AVIATION...OKeefe FIRE WEATHER...HWJIV HYDROLOGY...HWJIV/NAS
AREA FORECAST DISCUSSION
National Weather Service Bismarck ND
1139 PM CDT SUN MAY 22 2016 .UPDATE... Issued at 1139 PM CDT Sun May 22 2016 We just made another quick update to remove one more row of counties from the severe thunderstorm watch...including Burleigh County. Thus, Bismarck is no longer in the watch. UPDATE Issued at 1040 PM CDT Sun May 22 2016 Quick update to cancel the western parts of severe thunderstorm watch 192. The effective cold front, which has been partly re- inforced by storm outflow, has moved east of a Minot to Fort Yates line as of 0330 UTC. The severe threat has ended west of the front. We are maintaining the watch east of there for now given modest instability and moderate to strong deep-layer shear, but radar trends suggest the severe threat is marginal. UPDATE Issued at 859 PM CDT Sun May 22 2016 MODERATE INSTABILITY REMAINS OVER CENTRAL INTO EASTERN NORTH DAKOTA ALONG WITH SUFFICIENT DEEP LAYER SHEAR TO RESULT IN A CONTINUED SEVERE THREAT AHEAD OF A COLD FRONT DROPPING THROUGH CENTRAL NORTH DAKOTA. STORMS HAVE HAD TROUBLE BECOMING VERY STRONG...THOUGH HAVE HAD REPORTS OF PROLIFIC SMALLER HAIL PRODUCING STORMS ALONG WITH HEAVIER RAIN PRODUCERS OVER THE JAMES RIVER VALLEY REGION WHERE HIGHEST PRECIPITABLE WATER VALUES WERE NOTED. SOME POST FRONTAL STORMS ALSO CONTINUE TO DEVELOP WHICH MAY BE SPAWNED BY AN UPPER LEVEL JET STREAK LIFTING THROUGH THE REGION. WILL KEEP CURRENT SEVERE WATCH IN TACT. UPDATE Issued at 605 PM CDT Sun May 22 2016 Thunderstorms are starting to develop over western into south central North Dakota. Stage is still set with increased instability and sufficient deep layer shear to support severe storms with large hail and damaging wind gusts as the main threats. Plenty of moisture continues to surge in ahead of gradually progressing cold front (dewpoints in the lower 60s) to bring the risk of heavy rainfall from some storms. The area with the greatest risk for this continues to be over south central North Dakota into the James River Valley. && .SHORT TERM...(This evening through Monday) Issued at 206 PM CDT Sun May 22 2016 Severe thunderstorms highlight the short term period The latest water vapor imagery shows a closed low circulating over Alberta with a 100kt jet streak stretched out from northeast Montana into central Wyoming. This jet streak nudges east into western North Dakota this evening. This will provide large scale ascent along a cold frontal boundary, now located from Portal to Stanley, and south into Hettinger. Dewpoints in the west are in the lower 40s while in central North Dakota moisture is higher with dewpoints near 60F. The cold front will slowly move east tonight, exiting the James River Valley between 09z-12z Monday. Visible imagery showing stratus eroding which will initiate and increase low level buoyancy and instability. The HRRR and NAM look to have a good trend with convection initiation. The most intense cells begin near Lemmon SD and develop within a corridor between Dickinson and Bismarck, and narrowing but continuously developing towards Minot from 4pm-7pm cdt. This consolidates into a line of thunderstorms that slides into the James River Valley this evening. Another area of severe and/or heavy rain develops in south central ND between 7pm and midnight. This is forecast to move northeast and expand into the James River Valley with heavy rainfall late evening into the overnight period. Large hail, damaging winds, and heavy rainfall continue as the main threats late this afternoon through tonight. Flash flooding possible in the southern James River Valley late this evening into the overnight period. More stable air shifts from west to east tonight ending the precipitation after midnight. .LONG TERM...(Monday night through Sunday) Issued at 206 PM CDT Sun May 22 2016 Broad trough over the western CONUS gradually works eastward towards the plains through the middle and end of the upcoming week. This will bring active cyclonic flow to the area, though models are having quite a bit of trouble with timing out individual short waves within the system. With that said, will keep chances for precipitation going given the active pattern. Near to slightly above average temperatures expected. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 1040 PM CDT Sun May 22 2016 Thunderstorms will gradually end from west to east tonight, but are forecast to linger longest over the James River Valley. Local IFR ceilings and visibilities with heavy rain and gusty winds are expected with some storms. VFR conditions are expected on Monday behind the cold front crossing the area tonight. && .BIS Watches/Warnings/Advisories... NONE. && $$ UPDATE...CJS SHORT TERM...KS LONG TERM...JJS AVIATION...JJS/CJS
AREA FORECAST DISCUSSION
NWS Tulsa OK
1247 PM CDT MON MAY 23 2016 .DISCUSSION... Showers and thunderstorms continue to persist across Osage County this afternoon as a 35kt low level jet continues to funnel into that area. The MCV continue across northeast Oklahoma with the majority of the convection associated with this feature fading. Have adjusted the pops and temperatures for this afternoon with the cloud cover expected to keep temperatures a few degree lower. && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ SHORT TERM...10
Area Forecast Discussion...UPDATED National Weather Service Norman OK 1205 PM CDT MON MAY 23 2016 .AVIATION...23/18Z TAF ISSUANCE... Tricky aviation forecast over the next several hours. Broken to overcast MVFR ceilings will continue to impact airfields and TAF sites across portions of central and southern Oklahoma through the mid to late afternoon. Across western Oklahoma and western north Texas, scattered to broken MVFR ceilings will continue to improve to VFR through the afternoon. The biggest concern for aviation will be thunderstorm development late this afternoon and evening across portions of western Oklahoma and western north Texas. Confidence in timing and coverage has increased for TAF sites across the southwest, including KCSM/KHBR/KLAW/KSPS. Therefore, utilized TEMPO groups, after 00Z for most. Expect a complex of storms to develop similar to last night, primarily impacting southern Oklahoma and northern Texas overnight. Kurtz && .PREV DISCUSSION... /issued 928 AM CDT MON MAY 23 2016/ UPDATE... Quick morning update to thunderstorm chances through this evening. DISCUSSION... Jumping on the forecast early this morning given the chance for severe storms developing on/just east of the Caprock and moving into far western north Texas and southwestern Oklahoma late this Afternoon and evening. Guidance, both traditional and mesoscale, are in decent agreement with the redevelopment of the dryline on the Llano Estacado and its mixing eastward through the mid afternoon across the Texas and Oklahoma Panhandles. Dew points across the Panhandles to central Oklahoma continue to reside in the low to mid 60s, with sites farther south in western north Texas already reaching the upper 60s to near 70s. the MCS that moved across southern Oklahoma and northern Texas overnight has had some impact, but recovery is already well underway farther west. The fly in the ointment at the moment is the broken to overcast stratus spread across the area. In western Oklahoma, breaks have been fairly evident, and temperatures are already in the upper 60s and lower 70s. Agree with the night shift and with latest SPC outlook, some form of a triple point will develop south/southwest of the Red River, east of the Caprock this afternoon. Solutions from the HRRRx and TTU WRF continue to pick this as the primary initiation point. The operational HRRR and traditional guidance continue to fire convection along a surging point in the dryline early this afternoon in northwestern Oklahoma/southwestern Kansas. This is likely overdone given the current conditions, overcast skies, limiting heating this morning. However, isolated thunderstorms may develop in the region, but probably not as widespread as some of the solutions attempt. Therefore, increased precip chances to likelys across southern Oklahoma and western north Texas from late this afternoon through the evening and into the overnight hours. Confidence is high for storm development and and increase from chance PoPs was necessary. Not to rehash the previous discussion, but instability and shear will be plenty enough for the development of large damaging hail, damaging winds, and the possibility of a few tornadoes. Of greater concern for many will be the potential for flooding overnight, especially across portions of southern Oklahoma and northern Texas where excessive rainfall fell last night and this morning. Once again, this afternoon`s storms are expected to merge into a complex and propagate eastward overnight, slowly. A flood watch is in effect for this region and may need to be extended, but this will be addressed with the afternoon forecast. Kurtz PREV DISCUSSION... /issued 850 AM CDT MON MAY 23 2016/ UPDATE... Updated pops and slowed diurnal warming trend this morning. DISCUSSION... Showers/storms continue to move east with a new area of storms that developed just east of OKC/Norman. Have updated short-term pops with the latest trends in radar and satellite. HRRR/RAP and various hi-res models show redevelopment before 18z across northwest and central Oklahoma so have adjusted late morning pops to account for this possibility. And made significant changes to the hourly temperatures and dewpoints given the cloud cover will keep temperatures cooler this morning and the post-convective worked over airmass keeping dewpoints lower. Still expect we will see eventual recovery to forecast highs, but it will likely take some time. PREV DISCUSSION... /issued 659 AM CDT MON MAY 23 2016/ DISCUSSION... Please see the 12Z aviation discussion below. AVIATION... A few thunderstorms remain near SPS and OKC/OUN early this morning, and may continue for a couple more hours. Otherwise, expect MVFR cigs to return late this morning for a few terminals before becoming VFR by this afternoon. Showers and thunderstorms are expected again tonight, mainly after 00Z. Confidence in timing is not exceptional, however, so expect some amendments/changes to future TAFS. PREV DISCUSSION... /issued 405 AM CDT MON MAY 23 2016/ DISCUSSION... An MCS continues its track across southern OK and north TX early this morning. Very heavy rainfall and damaging winds accompanied it earlier, and are still expected across southern OK through the early morning hours. Most of this activity should move out of our area near or before sunrise. Later this afternoon storms will initiate along the dryline again from the southeastern TX panhandle into western and northwestern OK, and move east during the evening hours. Supercells will be likely, with ALL severe weather threats possible. The highest rainfall totals are again expected over western and southwestern OK, and western north TX. These areas already received a significant amount of rainfall this morning so we have decided to issue a Flood Watch thru early Wed AM. The overall forecast has changed very little for the work week. The severe threat will continue to shift slowly east each day with the dryline and approaching upper trough. The tornado threat should also increase during the late afternoon and early evening hours with the onset of the LLJ, especially across western and southwestern OK by Tue. There may be a break in COVERAGE Wednesday with surface convergence becoming a bit more diffuse along the dryline. However, if any isolated supercells can manage to develop they will again be capable of producing ALL severe weather threats. By Thursday, a southern stream mid to upper level shortwave trough is expected to lift over northeast TX and into SE OK around mid day. Heavy rainfall and embedded supercells will be possible with this activity. Further west, the upper trough will begin to near the southern plains with rapid height falls and increasing mid to upper flow expected over the dryline across western OK. Widespread severe weather continues to appear possible thru Thursday night, including the threat of tornadoes. Finally, by Friday, the upper trough will being to lift northeastward but will not pass overhead until late Friday night. Additional severe weather will remain possible from along/just west of I35 through eastern OK. Additional storm chances are expected through the weekend and into early next week as another upper trough moves over the western CONUS and WSW flow aloft ahead of it continues over the Southern Plains. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 67 83 68 86 / 50 20 50 20 Hobart OK 68 87 69 90 / 60 50 40 20 Wichita Falls TX 69 87 71 90 / 70 30 30 20 Gage OK 67 91 64 93 / 40 20 30 10 Ponca City OK 68 83 69 88 / 40 30 50 20 Durant OK 70 83 70 84 / 50 30 40 20 && .OUN Watches/Warnings/Advisories... OK...Flood Watch from 3 PM CDT this afternoon through Wednesday morning for OKZ021>023-027-033>039-044-045. TX...Flood Watch from 3 PM CDT this afternoon through Wednesday morning for TXZ083>090. && $$ 09/04/04
AREA FORECAST DISCUSSION
NWS Tulsa OK
928 AM CDT MON MAY 23 2016 .DISCUSSION... The Overnight MCS across southern OKlahoma and northern Texas has left an MCV over northeast Oklahoma this morning. This feature will continue to have convection associated with it for the next several hours as it moves off to the northeast with adequate elevated instability in place. The convection may become a little more concentrated around the MCV with the activity further south diminishing. Have made some adjustment to the pops for Today to take this into account. && .PREV DISCUSSION... /ISSUED 549 AM CDT MON MAY 23 2016/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. Ongoing convection now entering eastern OK will continue to spread eastward through the morning. The most likely aviation impact will be across SE OK nearer the stronger storms. Thinking is that once this convection dissipates then any redevelopment will be most likely west of the area with storms possibly spreading into the area early Tuesday morning. PREV DISCUSSION... /ISSUED 435 AM CDT MON MAY 23 2016/ DISCUSSION... The synoptic features from yesterday remain largely in play and nearly in the same locations early this morning. The one exception is that the ridge of high pressure has shifted east southeast some...becoming more positively tilted as the longwave trof settled over the Desert Southwest United States. Also this morning...the dryline off the surface low over Eastern Colorado continued to extend southward into far Eastern New Mexico. Scattered convection that had developed yesterday along the dryline had formed into a MCS across Southern Oklahoma... approaching Southeast Oklahoma over the next couple of hours. Across the rest of Eastern Oklahoma and Northwest Arkansas... cloudy conditions with east to southeasterly winds were common. The MCS will continue to push eastward into/across Southeast Oklahoma this morning and potentially spreading into Northeast Oklahoma and Northwest Arkansas this afternoon. An instability axis remained just west of the CWA this morning...which could help to weaken the overall intensity of the MCS...however gusty to locally damaging winds could be possible with this activity. Also...additional showers and thunderstorms will be possible across the CWA through this evening as any leftover outflow boundaries from the morning activity remain over the region. Breezy southerly winds transporting moisture back into the region combined with near seasonal average temperatures underneath a destabilizing atmosphere could allow for any thunderstorm activity through this evening to become strong to severe with large hail and locally damaging winds being the main threats. The greater severe potential though should remain west of the CWA...closer to the dryline. Also this afternoon...additional convection is expected to fire along/near the dryline again...which will have the potential to cluster together into another MCS and move into the CWA overnight tonight. The instability axis overnight tonight looks to be a little more eastward than where it is this morning. This will aid in a continued severe potential overnight tonight over the CWA...with locally damaging winds being possible. Tuesday through Thursday...the longwave trof is forecast to stall over the Southwest United States with west to southwesterly upper level flow over the Plains. Weak impulses within this flow moving across the Plains along with the dryline remaining over Western Kansas and the Oklahoma/Texas Panhandles will give a "rinse-wash- repeat" for thunderstorm chances each day over the CWA. Any convection along the dryline could form into an MCS at night and approach/move into the region...with additional daytime thunderstorm chances as the weak impulses interact with any leftover outflow boundaries. These conditions along with a continued unstable atmosphere will allow at least limited severe potentials through Thursday over Eastern Oklahoma and Northwest Arkansas. Latest model solutions continue to show the wave over the Southwest United States finally lifting into the Plains Friday...thus increasing thunderstorm chances again for the CWA. Indications are that the wave could possibly move into the region during the morning hours which could help to limit severe potential...though with this several days away...will continue to monitor latest data as this set up could likely change back-and- forth several times. For the upcoming weekend...thunderstorm chances will continue to be possible as another wave looks to quickly develop and lift out of the Southwest United States into the Plains. && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ SHORT TERM...10
Area Forecast Discussion...UPDATED National Weather Service Norman OK 928 AM CDT MON MAY 23 2016 .UPDATE... Quick morning update to thunderstorm chances through this evening. && .DISCUSSION... Jumping on the forecast early this morning given the chance for severe storms developing on/just east of the Caprock and moving into far western north Texas and southwestern Oklahoma late this Afternoon and evening. Guidance, both traditional and mesoscale, are in decent agreement with the redevelopment of the dryline on the Llano Estacado and its mixing eastward through the mid afternoon across the Texas and Oklahoma Panhandles. Dew points across the Panhandles to central Oklahoma continue to reside in the low to mid 60s, with sites farther south in western north Texas already reaching the upper 60s to near 70s. the MCS that moved across southern Oklahoma and northern Texas overnight has had some impact, but recovery is already well underway farther west. The fly in the ointment at the moment is the broken to overcast stratus spread across the area. In western Oklahoma, breaks have been farily evident, and temperatures are already in the upper 60s and lower 70s. Agree with the night shift and with latest SPC outlook, some form of a triple point will develop south/southeast of the Red River, east of the Caprock this afternoon. Solutions from the HRRRx and TTU WRF continue to pick this as the primary initiation point. The operational HRRR and traditional guidance continue to fire convection along a surging point in the dryline early this afternoon in northwestern Oklahoma/southwestern Kansas. This is likely overdone given the current conditions, overcast skies, limiting heating this morning. However, isolated thunderstorms may develop in the region, but probably not as widespread as some of the solutions attempt. Therefore, increased precip chances to likelys across southern Oklahoma and western north Texas from late this afternoon through the evening and into the overnight hours. Confidence is high for storm development and and increase from chance PoPs was necessary. Not to rehash the previous discussion, but instability and shear will be plenty enough for the development of large damaging hail, damaging winds, and the possiblity of a few tornadoes. Of greater concern for many will be the potential for flooding overnight, espcecially across portions of southern Oklahoma and northern Texas where excessive rainfall fell last night and this morning. Once again, this afternoon`s storms are expected to merge into a complex and propogate eastward overnight, slowly. A flood watch is in effect for this region and may need to be extended, but this will be addressed with the afternoon forecast. Kurtz && .PREV DISCUSSION... /issued 850 AM CDT MON MAY 23 2016/ UPDATE... Updated pops and slowed diurnal warming trend this morning. DISCUSSION... Showers/storms continue to move east with a new area of storms that developed just east of OKC/Norman. Have updated short-term pops with the latest trends in radar and satellite. HRRR/RAP and various hi-res models show redevelopment before 18z across northwest and central Oklahoma so have adjusted late morning pops to account for this possibility. And made significant changes to the hourly temperatures and dewpoints given the cloud cover will keep temperatures cooler this morning and the post-convective worked over airmass keeping dewpoints lower. Still expect we will see eventual recovery to forecast highs, but it will likely take some time. PREV DISCUSSION... /issued 659 AM CDT MON MAY 23 2016/ DISCUSSION... Please see the 12Z aviation discussion below. AVIATION... A few thunderstorms remain near SPS and OKC/OUN early this morning, and may continue for a couple more hours. Otherwise, expect MVFR cigs to return late this morning for a few terminals before becoming VFR by this afternoon. Showers and thunderstorms are expected again tonight, mainly after 00Z. Confidence in timing is not exceptional, however, so expect some amendments/changes to future TAFS. PREV DISCUSSION... /issued 405 AM CDT MON MAY 23 2016/ DISCUSSION... An MCS continues its track across southern OK and north TX early this morning. Very heavy rainfall and damaging winds accompanied it earlier, and are still expected across southern OK through the early morning hours. Most of this activity should move out of our area near or before sunrise. Later this afternoon storms will initiate along the dryline again from the southeastern TX panhandle into western and northwestern OK, and move east during the evening hours. Supercells will be likely, with ALL severe weather threats possible. The highest rainfall totals are again expected over western and southwestern OK, and western north TX. These areas already received a significant amount of rainfall this morning so we have decided to issue a Flood Watch thru early Wed AM. The overall forecast has changed very little for the work week. The severe threat will continue to shift slowly east each day with the dryline and approaching upper trough. The tornado threat should also increase during the late afternoon and early evening hours with the onset of the LLJ, especially across western and southwestern OK by Tue. There may be a break in COVERAGE Wednesday with surface convergence becoming a bit more diffuse along the dryline. However, if any isolated supercells can manage to develop they will again be capable of producing ALL severe weather threats. By Thursday, a southern stream mid to upper level shortwave trough is expected to lift over northeast TX and into SE OK around mid day. Heavy rainfall and embedded supercells will be possible with this activity. Further west, the upper trough will begin to near the southern plains with rapid height falls and increasing mid to upper flow expected over the dryline across western OK. Widespread severe weather continues to appear possible thru Thursday night, including the threat of tornadoes. Finally, by Friday, the upper trough will being to lift northeastward but will not pass overhead until late Friday night. Additional severe weather will remain possible from along/just west of I35 through eastern OK. Additional storm chances are expected through the weekend and into early next week as another upper trough moves over the western CONUS and WSW flow aloft ahead of it continues over the Southern Plains. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 81 67 83 68 / 30 50 20 50 Hobart OK 83 68 87 69 / 40 60 50 40 Wichita Falls TX 84 69 87 71 / 20 70 30 30 Gage OK 89 67 91 64 / 30 40 20 30 Ponca City OK 81 68 83 69 / 40 40 30 50 Durant OK 83 70 83 70 / 80 50 30 40 && .OUN Watches/Warnings/Advisories... OK...Flood Watch from 3 PM CDT this afternoon through Wednesday morning for OKZ021>023-027-033>039-044-045. TX...Flood Watch from 3 PM CDT this afternoon through Wednesday morning for TXZ083>090. && $$ 09/04
AREA FORECAST DISCUSSION
NWS Tulsa OK
1144 PM CDT SUN MAY 22 2016 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. Convection across western OK will make a run at eastern OK and have introduced VCTS for the OK TAF sites around 10z...with VCSH for the AR sites toward 15z. While brief MVFR conditions can`t be ruled out...expect mainly VFR through the period. && .PREV DISCUSSION... /ISSUED 853 PM CDT SUN MAY 22 2016/ ..UPDATE... DISCUSSION... Ongoing thunderstorms in the eastern panhandles making slow eastward progress. The expectation continues that much of this will diminish before reaching eastern Oklahoma, with perhaps only areas along and west of Highway 75 seeing any remnants. Of this area, it appears that parts of southeast Oklahoma would be the most favored at this point, given recent data from the HRRR and current location of the most developed area of convection. Have made a few minor tweaks to the POPs after 06Z to account for this thinking, as well as minor changes to the Sky grids to spread cloud cover into northwest Arkansas faster. Updated forecast products coming soon. PREV DISCUSSION... /ISSUED 623 PM CDT SUN MAY 22 2016/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. VFR conditions expected through the period. Scattered showers and thunderstorms possible for eastern OK TAF sites late tonight and into Monday morning. PREV DISCUSSION... /ISSUED 359 PM CDT SUN MAY 22 2016/ DISCUSSION... The upper ridge is shifting off to the east and we will be under the influence of the western U.S. trough for at least the next week or so. The dryline will remain well to our west for most of the week, but we will be at risk of seeing at least the remnants of any storms that develop well to our west making it far enough east to affect us. Weak impulses moving out of the western trough may also trigger scattered showers and storms within our forecast area just about any day this week. Instability will be sufficient for severe storms, especially from Tuesday on. The main upper system will finally lift northeast into the central Plains by Friday, perhaps 12 hours or so sooner than it appeared at this time yesterday. Thus Friday will likely see the greatest precipitation coverage, and greatest severe weather risk, of the week. Even after this system lifts out, another trough develops near the West Coast, and the dryline gets left behind to our west, so storm chances will continue through next weekend, as will the warm and humid conditions. Stayed close to guidance temperatures the next couple days. TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. $$ && .PRELIMINARY POINT TEMPS/POPS... TUL 66 83 69 85 / 10 40 30 30 FSM 62 86 67 84 / 10 30 20 30 MLC 67 83 70 82 / 20 30 30 30 BVO 64 82 67 84 / 10 40 30 30 FYV 58 82 64 80 / 0 20 20 30 BYV 58 82 64 80 / 0 20 20 30 MKO 63 83 68 83 / 10 30 30 30 MIO 63 83 67 82 / 10 30 30 30 F10 66 82 69 83 / 20 40 30 30 HHW 65 85 69 84 / 30 30 30 30 && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ AVIATION...18 Area Forecast Discussion National Weather Service Taunton MA 229 AM EDT WED MAY 25 2016 .SYNOPSIS... A few leftover showers may fall across western MA and north central Conn., as well as south coastal MA and RI through the early this morning as low pressure slowly moves northeast to the Gulf of Maine. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 145 AM Update... H5 cutoff low has pushed just E of Cape Cod as seen on latest water vapor and IR satellite imagery. Winds have diminished to near calm away from the coast at 05Z obs. Noting patchy dense fog has started to form across portions of the CT valley into NE CT. May see more develop over the next few hours across central and western areas. May also see a few showers develop with the last of the band crossing out the Berkshires through 08Z-09Z. Remainder of previous forecast in pretty good shape, but have updated to bring current. Previous discussion... With light winds across the region, along with lowering temp/dewpoint spreads, will still see patchy fog develop along with lingering low clouds from around Worcester and Windham counties eastward through around midnight, but trends continue to indicate that this should slowly push E during the early morning hours as the low exits, but will be slowest across E coastal MA. Partial clearing should begin moving into the CT valley after midnight as winds back to light NW, then will slowly shift E overnight. Clouds will linger along the E coast through daybreak. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/... *** Summer-like Temperatures Move in Today *** Today ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through 12Z...Moderate confidence, though lower in timing of improving conditions toward daybreak. Areas of IFR-LIFR CIGS and mixture of VFR to IFR VSBYS in patchy fog, lowest across interior E MA and portions of CT valley into NE CT. Should start to see conditions improve to VFR across CT valley after 08Z, then slowly progressing E after daybreak. Calm or light/vrbl winds. Today...Moderate confidence this morning, then high confidence. IFR CIGS and areas of MVFR-IFR VSBYS across central-E MA/RI should improve by mid morning. Otherwise, VFR. W-SW winds 10 kt or less. Tonight...High confidence. VFR conditions. W-NW winds less than 10 kt. Thursday...High confidence. VFR. Light W-NW winds, except sea breezes possible late morning/afternoon along the coast. KBOS TAF...Moderate confidence. Uncertain on exact timing of improvement, but should take place by around 10Z. KBDL TAF...Moderate confidence. otherwise VFR. Outlook /Thursday Night through Sunday/... Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through 12Z...High confidence. Upper level low will slowly move into Massachusetts Bay during the early morning hours. Light E-NE winds across the eastern waters will back to N-NW, becoming mainly W of all waters toward daybreak. Leftover SE swells will linger on the outer waters E and S of Cape Cod, but should subside below 5 ft by around 08Z- 09Z. Visibility restrictions in patchy fog, locally dense in some locations, should improve from W-E. Today...High confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Tonight...High confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday Night through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... Wednesday...High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given today`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for MAZ020>024. RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for RIZ003-004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT early this morning for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...EVT SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Dunten/EVT MARINE...Nocera/Dunten/EVT FIRE WEATHER...Staff
  [top] Area Forecast Discussion National Weather Service Albany NY 210 AM EDT WED MAY 25 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... As of 210 AM EDT...showers have dissipated across all of our region, and so have many of the clouds. However, as moisture pooled from the Hudson valley eastward, patchy dense fog was beginning to form from the Hudson valley eastward with dewpoints still around 50 or higher, compared to much lower levels just west, where they were from the upper 30s to mid 40s. At this time of night, with decoupling, there really is no way for these dewpoints to advect further east, so we don`t expect much in them overnight. We did however, lower some places a couple of degrees. Look for lows generally 45-50 with light or calm wind. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... It looks as if we will dealing with quite a bit of IFR flying conditions through 11Z thanks to residual low level moisture trapped in the Hudson valley and Berkshires. This despite our local Fog study program did not forecast any fog in any of the TAFs. As of 06Z Low IFR was already reported at KGFL and KPSF. While KALB was still VFR their remarks indicated patches of fog (BCFG) so we believe they too will have at least temporary times of IFR. KPOU looks to have some IFR fog although studies have indicated it is hard to fog at the site. Any and all fog will be gone before 12Z leaving us to a VFR flying day as dry air will mix down as a breeze kicks in from the west, 5- 10KTS, gusting to 20KTS by midday at KPSF and KALB. After 12Z clouds will be few-sct with some cumulus around 5 KFT and a few higher clouds at times. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...HWJIV/BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...HWJIV/BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS
  [top] Area Forecast Discussion National Weather Service New York NY 959 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure departs to the northeast as high pressure builds to the south on Wednesday. A cold front moves through on Thursday. High pressure will then dominate through Saturday night as a series of weak upper level disturbances move across. A cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. persistent showers continue to track down from new england...so have added chc pops for a few more hours as a weakening trend is noted on radar as well as in the hrrr. dry weather should return by midnight with decreasing clouds overnight. have also added patchy fog to ct coastal areas and ern long island overnight with light winds and high moisture content at the sfc. Otherwise...minor adjustments made to hourly t/td. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. With lighter winds across the interior, min temperatures were further lowered by a degree. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south overnight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light overnight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... light pcpn amounts (less than 1/10 inch) in any remaining showers this eve. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
Area Forecast Discussion National Weather Service Albany NY 812 PM EDT TUE MAY 24 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... As of 800 PM EDT...Weak deformation axis association with scattered to broken band of showers just east of the Hudson River should continue into the evening hours. The upper low in the vicinity of Providence, RI is beginning to show signs of tracking ENE per the latest H2O loop analysis. With this movement we should see a diminishing trend in the showers which too is suggested by the HRRR. So main update was to the sky coverage, PoPs/WX, removed the mention of thunder and expanded the fog a little further west to include the Hudson River Valley overnight as skies should clear overnight under diminishing winds. Question will be just how much fog impact will occur as dewpoints upstream were between 30-40F compared to mid 50s across eastern NY. We will monitor closely. Prev disc...Upper low departing northeast slowly but steadily. Very narrow band of rain in eastern NY with some isolated thunderstorms from the Berkshires through NW CT and the mid Hudson Valley. Rain and isolated thunderstorms will build east and dissipate through the evening...and clearing will take place through the night. Quite a bit of clearing outside of the moisture field of the upper low...so by daybreak most areas should be clear to mostly clear. There could be some patchy fog as low level winds should trend to calm and areas with wet ground could support some patchy fog but with dryer surface dewpoints advecting in...it could minimize chances for fog. Only including patchy fog for areas east of the Hudson Valley into western New England where most of the rain has fallen. Lows in the mid 40s to lower 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Showers continue to impact the Hudson River Valley and points east which is mainly where our TAFs are located. Included a VCSH or a TEMPO group for the next few hours. Otherwise, VFR conditions through the evening hours. The question for tonight will be how much BR/FG form. All terminals will clear out overnight. Winds will be light but dewpoints upstream are about 10-15 degrees cooler than those observed across eastern NY and western NE. At this time, the best IFR chances for FG are at KPSF/KGFL where showers and trapped moisture near the inversion. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS www.weather.gov/albany
Area Forecast Discussion National Weather Service New York NY 737 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. High pressure will dominate through Saturday night as a series of weak upper level disturbances move across. A back door cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. Made some adjustments to pops next couple of hours based on latest radar trends. Showers continue to weaken this eve and dry weather should return by midnight. Otherwise...minor adjustments made to hourly t/td and winds. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. Also with lighter winds across the interior and residual low level moisture...there could be some patchy fog late into early Wednesday Morning. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /23Z TUESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south tonight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light tonight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: No unscheduled amendments this evening. A late day seabreeze is expected Wednesday. KLGA TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KEWR TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KTEB TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KHPN TAF Comments: Patchy fog is possible overnight. West winds will increase by afternoon with occasional gusts expected. KISP TAF Comments: No unscheduled amendments this evening. A late day seabreeze may approach the airport Wednesday, but do not expect the seabreeze to move through at this time. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected into early this evening. Locally higher amounts will be possible in thunderstorms. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
Area Forecast Discussion National Weather Service Taunton MA 703 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers will continue across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 700 PM Update... Overall forecast is on track. Removed the thunder mention for this evening as convection has remained just west of southern New England. Also increased precip trends across RI and southeast MA as area of showers continues to develop and spin as the upper level low begins to slowly shift eastward. Otherwise breaks of sun across western MA as allowed for temps to warm in to the upper 60s late this afternoon. Onshore flow across eastern MA will continue until the low shifts eastward creating more of a northerly flow. Fog and drizzle will remain over the next several hours. May need to watch for radiational fog development tonight across the low lying areas as lingering low level moisture combined with cooling temperatures will create a low temp/dewpoint spread. Dense fog is not expected at this time. Previous Discussion... An area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Isolated lighter showers east of the Worcester Hills tonight. Mainly MVFR all terminals except Coastal MA which will see periods of IFR. VFR across the CT valley. Cigs and vsby improve from west to east after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...Nocera/Dunten SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Nocera/Dunten MARINE...Nocera/Dunten FIRE WEATHER...
Area Forecast Discussion National Weather Service Taunton MA 411 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers and isolated embedded thunderstorms over Western portions of MA and CT will continue into early this evening. Scattered showers may also develop across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 400 PM Update ... Vertically stacked low over the region with -19c air at 500 mb. This cold air aloft combined with cyclonic flow is resulting in scattered showers and embedded thunder. The convection is focused on the western side of the low where SPC mesoanalysis indicates some baroclinicity at 850 mb and 925 mb along with some breaks of sunshine yielding 250-500 j/kg of SB cape per mesoanalysis. This will continue to be the theme thru sunset with convection focused across this region. A second area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Highlights... * Very warm Wed/Thu/Fri with highs well up into the 80s except cooler immediate coast at times * Hot Saturday afternoon w/highs mainly upper 80s to the lower 90s * A few showers/t-storms possible Thu night/Fri but best chance Sat afternoon/evening ahead of cold front * Turning much cooler Sun and especially Mon along the coast Details... Wednesday night...Other than a low risk for a spot shower/t-storm across the interior during the evening dry weather is expected behind a weak cold front. Low temps will only fall back into the 50s in most locations with 60 to 65 in some of the urban centers. A touch of patchy fog may develop in the typically prone locations toward daybreak. Thursday...Upper level ridging across the Southeast U.S. continues to nose into southern New England. This will result in plenty of sunshine and with warm mid level temps, highs again should reach well into the 80s in most locations. However, gradient will be weaker allowing for sea breezes to develop on the immediate Eastern MA coast including Boston by early afternoon. High temps will still likely reach well up into the 70s to near 80 in this region before sea breezes develop and temps fall a bit. Should remain dry given lack of forcing and upper level ridging nosing into this region. Thursday night and Friday...A shortwave will lift northeast into northern New England Thu night/Fri. While the best forcing will to our north, a few showers/t-storms are possible with the best chance across western and northern MA. Certainly not expecting a washout though and the majority of the Thu night/Fri will be dry. Still looks like a warm afternoon with temps into the 80s, but it may be cooler across Northeast MA depending on location of backdoor cold front. Saturday...A hot day with westerly flow and 850T near 16c. This should yield highs in the upper 80s to lower 90s for most locations. Dewpoints into the 60s will make it feel somewhat muggy. Pre-frontal trough ahead of an approaching cold front may trigger scattered showers/thunderstorms mainly Saturday afternoon and evening. Sunday and Monday...High pressure over the Canadian Maritimes will build south into New England. So despite rather high height fields, northeast low level flow will result in much cooler temps Sun and especially Mon particularly along the coast. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Some improvement in vsbys observed over past 1 to 2 hours but cigs slow to rise in onshore flow across much of the area. Believe will begin to rise into the VFR range across the CT River Valley by mid afternoon. Rest of the area should see very slow improvement into at least low MVFR cig range, although there could be a few holdouts below one thousand feet in SE coastal areas. Scattered showers and even isolated thunderstorm or two could develop late this afternoon/evening over portions of RI and SE MA. There could also be scattered showers/isolated thunderstorms that develop during the late afternoon near the Berkshire Crest. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Showers with isolated thunder focused across Western portions of MA and CT. Isolated lighter showers elsewhere. Mainly MVFR all terminals except Coastal MA. Showers dissipate with sunset and cigs and vsby improve after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Showers should stay west of BDL airspace but will be close and need to watch early this evening. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR conditions other than a few hours of patchy ground fog possible toward daybreak Thu in the typically prone locations. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period with the exception being Wednesday night. Some brief near shore southwest wind gusts of 20 to 25 knots are likely Wed afternoon...which will result in some choppy seas. In addition, long southwest fetch may bring a period of 5 foot seas across our southern waters Wednesday night which may require headlines. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera NEAR TERM...Nocera SHORT TERM...Nocera LONG TERM...Frank AVIATION...Frank/Nocera MARINE...Frank/Nocera FIRE WEATHER...Nocera
Area Forecast Discussion National Weather Service New York NY 248 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. This lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... Higher vorticity advection associated with residual cold pool aloft with lingering upper level low combined with increased daytime heating has led to scattered showers and thunderstorms. Some gusty winds and small hail as well as heavy rain are possible for brief periods of time with these thunderstorms. Most of the convection has been confined to Southwest Connecticut and Western Long Island Sound. With CAPE values forecast of a few hundred J/KG more showers and thunderstorms will be possible with coverage being scattered. This will decrease with loss of diurnal heating and as cold pool aloft shift farther east this evening. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... For tonight, the region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest into early this evening. Locally higher amounts will be possible in thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/JP NEAR TERM...JM SHORT TERM...JM LONG TERM...JP AVIATION...MPS MARINE...JM/JP HYDROLOGY...JM/JP
Area Forecast Discussion National Weather Service New York NY 150 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast today and tonight, moving along the New England coast. High pressure builds in briefly for late tonight and Wednesday. A cold front moves through late Wednesday night into Thursday morning and lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... The forecast is pretty much on track here. There were some slight adjustments to better match observed trends with regards to temperatures, dewpoints, and pops for showers. Otherwise though, no remarkable changes were made to the forecast database. A weakening low south of Cape Cod tracks slowly northeast through today. A weak surface trough extends back from the low into the lower Hudson Valley. Meanwhile an upper closed, and nearly cutoff low, east southeast of the Delmarva, as seen on the water vapor loop, drifts north to northeast and begins to fill and get picked up by the northern stream. With areas of energy rotating around the low and the surface low, showers will continue through this morning, eventually becoming more scattered this afternoon. Instability is very weak this morning and generally less than 50 J/KG but this will increase this afternoon to a few hundred J/KG with increased daytime heating at the surface. Forecast includes isolated thunderstorms this afternoon. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Tonight the upper low continues to fill and becomes an open wave after 06Z and the northern stream carries the low into Maine and Nova Scotia, merging with low pressure over eastern Canada. The surface low becomes nearly indistinguishable by late tonight, also merging with a surface low over eastern Canada. By 00Z precipitation is quickly ending as heights rise from as weak upper ridging builds to the west. This ridge builds through Wednesday with dry weather late this evening through Wednesday. Warmer air continues to move into the region tonight through Wednesday at the lower and mid levels. A dramatic warmup is expected across the entire region as a westerly flow allows even coastal areas to warm to well above seasonal normals. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http://www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday as a weakening low south of Cape Cod tracks to the northeast through tonight and high pressure builds in late tonight and Wednesday. The only hazard across the forecast waters will be isolated thunderstorms this afternoon into early this evening. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest of today into this evening. Locally higher amounts will be possible in isolated thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP/MET NEAR TERM...JM/MET SHORT TERM...MET LONG TERM...JP AVIATION...MPS MARINE...JM/JP/MET HYDROLOGY...JP/MET
Area Forecast Discussion National Weather Service Albany NY 147 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure over southeast Long Island will bring scattered to numerous showers across our region from the Capital District south and east today with perhaps a rumble of afternoon thunder. Clouds will keep temperatures a little less warm than yesterday. This storm will move to our east tonight and high pressure will briefly build in through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 134 PM EDT...A closed off upper level low is located just southeast of the region off the coast of southern New England to the east of Long Island. Moisture wrapping around this feature continues to allow for some showers. The bulk of these have been occurring over southern Vermont and into adjacent Washington and Rensselaer Counties New York. Some parts of southern Vermont have seen locally around an inch of rainfall according to the latest MRMS precip estimation. Temps continue to vary from northwest to southeast across the area this afternoon. Thanks to partly to mostly sunny skies, some parts of the central/western Adirondacks have already reached into the mid 70s, while southern and eastern areas seeing lots of clouds remain only in the low 60s. Temps look to be fairly steady for the afternoon hours, with the warmest readings in northwest parts of the area. Most places from Albany on south/east won`t see much sun for the remainder of the day. The latest 16z 3km HRRR suggests that the threat for showers will remain in the forecast for this afternoon, mainly for areas east of the Hudson River. There might be enough instability with colder temperatures aloft for an isolated thunderstorm this afternoon, although most areas won`t see any thunder. Will continue with just a slight chance of thunder for much of the area. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... The cutoff low is forecast to drift east of Cape Cod tonight taking all the showers with it. Weak high pressure will build tonight into early Wednesday with a return to sunshine and higher temperatures back to 80-85 in the valleys, mid to upper 70s over the higher elevations. By afternoon, a weak back door front looks to slip southward into the Adirondacks touching off some scattered showers and possibly thunderstorms. One or two cells could make it south into the Capital region and even northern Catskills. A west to southwest wind 5-15 mph will become northwesterly during the afternoon. The front looks to washout by Wednesday night over the region as it slides to our south. Wednesday night looks dry with perhaps a little patchy fog as the wind will become light or calm overnight. Thursday will start out dry, but with increasing moisture, and perhaps a weak short wave, some scattered showers or thunderstorms could develop by afternoon across the region. These will be hit and miss with many areas likely not getting any rain at all. Otherwise, temperatures will climb in the mid or upper 80s in the valleys, 75-80 higher terrain. Dewpoints will reach the lower 60s in the Hudson valley south of Albany, mid or upper 50s further north so it will feel a little uncomfortably warm to some. && .LONG TERM /FRIDAY THROUGH MONDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. Friday-Friday night...the warm front finally moves through eastern NY and western New England during this time frame. A warm and humid air mass settles in...as dewpoints rise into the 60s. The boundary will likely be in the vicinity of the forecast area...and a weak short-wave in the west to southwest flow aloft will likely focus isolated to scattered showers and thunderstorms. The latest GFS20 has modest SBCAPEs in the 1000-2000 J/kg range, but the amount of deep shear remains uncertain. It is hard to ascertain if the convection will be severe this far out. H850 temps rise to +14C to +16C with highs in the lower to mid 80s in the valley locations...and mid 70s to around 80F over the mountains. The showers and thunderstorms should diminish quickly with the boundary retreating northward and the daytime heating gone. Lows will be upper 50s to lower 60s over most of the forecast area. Saturday-Saturday Night...The subtropical high builds in from the western Atlantic. The ALY forecast get into a warm sector. H850 temps nudge up to +15C to +17C on the latest ECMWF. PWATs increase to 1-1.5 inches. The GFS model soundings do not look very capped. Pop-up diurnally-driven showers and thunderstorms will be possible capable of heavy rainfall. The big question is the timing of the backdoor cold front from Northern New England and southeast Canada. The guidance varies on the timing and placement of the boundary. Our forecast reflects a timing more Saturday night into Sunday. Highs will be steamy for late May with humidity levels on the increase. Highs will be mainly in the mid and upper 80s for elevations at 1000 ft or lower...and upper 70s to lower 80s over the mountains. A slight to low chc of showers and thunderstorms will likely linger most of the night as the backdoor cold front dips south/southwest across the region. Sunday into Memorial Day...Temps look a bit cooler...closer to normal for late May on Sunday...as the backdoor cold front stalls over central NY...eastern PA and northern NJ. The ECMWF has H850 temps fall back to +10C to +12C from east to west over the forecast area...as the cold front moves through...and high pressure builds in from New Brunswick and Nova Scotia. There will continue to be solid chances of showers and thunderstorms as the cold front looks to move through. The amount of instability available will be the main issue for any strong to severe thunderstorms as the shear increases. This will continue to be monitored over the next several days. Highs on Sunday fall back into the mid 70s to lower 80s. Lows Sunday night fall back into the 50s to lower 60s. Memorial Day will feature a threat of a shower or thunderstorm...but it is uncertain where the frontal boundary goes. The latest WPC guidance has it move north into southern Quebec and Northern New England again. When a boundary is in the area with light to moderate amounts of instability and appreciable moisture...then a slight to low chc of showers and thunderstorms...especially in the afternoon will persist through the holiday weekend. Overall...it does not look like a washout at this point. After lows Sunday night in the 50s...highs will likely be in the 70s. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Still some spokes of precipitation rotating around the low pressure system to our east. Have VCSH at all terminals for the afternoon. Not out of the question that a terminal could drop to MVFR conditions in a shower...or perhaps IFR...but chances are slight. Slight chances for TSRA this afternoon as well...but not sufficient to warrant mention in TAFs. So will maintain VFR at all terminals this afternoon. Question for tonight will be how much BR/FG form. All terminals will clear out tonight. Winds will be light. Best chances for FG are at KPSF where showers deposited around 0.2 inch of rain today. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday through 18z. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA...TSRA. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: Moderate Operational Impact. Chance of SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... RH levels should remain elevated today dropping not low than about 50 percent most places. There will be scattered to numerous showers mainly from the Capital region south and eastward. Most areas will likely not receive a quarter inch, except perhaps Litchfield county into the Mid Hudson valley and southern Catskills. The showers will move out tonight leaving us with a nearly fully recovery and likely the formation of dew as the wind will be light. Wednesday, will start out dry and sunny. A weak disturbance could trigger scattered showers and thunderstorms mainly north of the Capital region but a few could stray further south. A full recovery tonight as the showers move out followed by warm increasingly humid weather for the balance of the week. Low pressure tracking close to southern New England will scattered to numerous showers from the Capital region and perhaps an afternoon thunderstorm to locations from the Capital Region south and east. Weak high pressure will build east off the mid Atlantic states and summer like weather will spread across our region from the southwest through the end of next week. The surface wind will be light out of the north or northeast through Tuesday, generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms today. At this time amounts up to a tenth of an inch in our northwestern zones, to quarter to half an inch in our southeastern zones is anticipated. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...HWJIV NEAR TERM...Frugis/HWJIV/OKeefe SHORT TERM...HWJIV LONG TERM...Wasula AVIATION...OKeefe FIRE WEATHER...HWJIV HYDROLOGY...HWJIV/NAS
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1248 AM CDT WED MAY 25 2016 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Wednesday) Issued at 324 PM CDT TUE MAY 24 2016 A familiar synoptic pattern is seen in the 19Z water vapor imagery. With a mean trough still over the west and northern Rockies, southwesterly flow aloft remains over the central plains. A surface low was again analyzed over the OK panhandle with a dryline extending south through west TX. Outflow from morning storms has muddled up the surface pattern over northeast KS and the better moisture convergence is appears to be over southwest KS between the surface low and the outflow boundary over southern KS. A lot of this forecast is based on expected persistence of the pattern and previous nights. Think that storms will once again develop over southwestern KS and congeal into an MCS moving across eastern KS tonight. The HRRR/ARW/NMM show a bowing MCS developing this evening and move it across the forecast area by the late evening. 0-6KM shear remains rather marginal around 30KT so the main concerns with the storms will be damaging winds, hail and localized flash flooding. Have likely POPs going tonight, but confidence is only medium as some of the models still show various tracks to the MCS. POPs taper down during the morning Wednesday as models move the storms through earlier in the night. Although if an MCV is slow to move east, there could be some lingering precip late in the morning. Lows tonight should be in the lower to mid 60s with rain cooled air helping to cool temps more so than they would be without precip. Highs Wednesday are forecast to be in the lower and mid 80s as models advect warmer air into eastern KS with 850MB temps warming to around 22C and 700MB temps between 8 and 10C. Because of this, forecast soundings show an elevated mixed layer capping the boundary layer through much of the afternoon. So the question becomes whether there is enough convergence along the dryline to force storms because large scale forcing again appears to be weak at best. Most guidance seems to keep the boundary layer capped as they do not generate much QPF in the afternoon, so have kept some small POPs in the forecast for Wednesday afternoon on the small chance a storm develops. .LONG TERM...(Wednesday Night through Tuesday) Issued at 324 PM CDT TUE MAY 24 2016 Wednesday Night Friday... Convective chances by early evening will be dependent on what mesoscale boundaries will be present from any convection earlier in the day. Otherwise the dryline and front will be located west of the forecast area. There is not much in the way of upper support, however the models suggest that there may be a weak wave moving out of western Kansas into Nebraska Wednesday night. Instability, moisture and shear will be sufficient for a few severe storms with hail and wind the main hazards and a low probability for tornadoes. Thursday may start out dry as models move off an MCS well east by 12Z Thursday. The models have slowed the ejection of the main energy ejecting out of the western trough, but do eject a lead shortwave out into the Plains Thursday afternoon and evening. Forecast soundings show Steepening lapse rates and increasing shear around 30 to 35 kts toward 00Z Friday along with mlcape around 2500 J/kg. Expect thunderstorms to develop along the front and dryline then move northeast and east across the CWA during the evening and overnight hours. Have maintained higher precipitation chances for Thursday night and Friday as the upper level trough advances out into the Plains. Forcing will also be aided by left exit region of the upper jet across central and north central Kansas on Friday. Any ongoing precipitation will likely leave mesoscale boundaries across parts of the area by Friday afternoon. Friday Night through Tuesday... The active spring pattern will continue through the extended period. Friday night an upper level trough across the four-corners region will eject northeastward into the central plains. A strong vort-max will will eject across the forecast area Friday evening into Saturday morning, bringing likely chances for thunderstorms across the entire area. Strong to severe thunderstorms will also be possible as sufficient CAPE and shear will be in place. The remainder of the period will consist of southwest flow aloft and embedded weak upper-level waves. With the plentiful boundary layer moisture that will be in place, have at least slight chance PoPs through the remainder of the period. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1247 AM CDT WED MAY 25 2016 Weakening TSRA complex moving through the terminals. Winds will be a challenge over the next few hours but should become south to southeast by 10Z. There continue to be signals of MVFR stratus into the 18z period and will go along at this point. Too much uncertainty for any late period TSRA at this point. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Wolters LONG TERM...Baerg/53 AVIATION...65
Area Forecast Discussion National Weather Service Goodland KS 1100 PM MDT TUE MAY 24 2016 .SHORT TERM...(Today through Thursday night) Issued at 249 AM MDT Tue May 24 2016 Due to current ongoing storms and severe weather will wait to issue the morning forecast until severe watch 202 is cancelled. Southwest flow will persist across the central plains from today through Thursday night. A surface trough will exist over eastern Colorado today and tonight. The trough will move into northwest Kansas Wednesday and Wednesday night and then align itself along the Colorado/Kansas border Thursday night. a shortwave is advertised to come through the flow this afternoon and evening. The surface wind field suggests convergence to support thunderstorm initiation across the northern fa. There is good instability and shear to produce severe thunderstorms. Subsidence moves into the fa Wednesdays morning behind the exiting shortwave. Even through there is an apparent weak disturbance in the flow WEDNESDAY afternoon, dynamics and instability are weak so will make pops nil until late evening when some lift is shown mainly across the far north fa. Subsidence follows Thursday morning so pops will be nil. A strong shortwave comes into the area Thursday afternoon and night. Good dynamics with this feature warrant higher chance pops. Max temperatures today through Thursday should range from the upper 70s in eastern Colorado to the lower 80s across northwest Kansas. Min temperatures tonight should cool to the 50s. .LONG TERM...(Wednesday night through Tuesday) Issued at 146 PM MDT Tue May 24 2016 Going into Wednesday night...weak surface low out over the Central Plains ahead of slow moving upper low/trough over the Rockies...will combine with a boundary over the Kansas/Nebraska border to bring some light rw/trw activity to mainly northern areas thru the overnight period. By Thursday as upper trough/low begins to shift eastward into the plains and exits the area slowly by late Friday. some mid level ridging will allow for periods of dry conditions going into the first half of the weekend...do expect increase in areal coverage of rw/trw late Saturday night on through the beginning of next week as a couple of shortwave move around the base of approaching upper low from the Pacific NW/Northern Rockies. The entire Tri State region will have chances for trw/rw for much of the extended period. Lowest probability will occur on Saturday as weak ridging occurs. Best chances for precip will occur Thursday and Thursday night with the arrival of the enhanced dynamics of the upper low combining with remnants of surface low/frontal boundary. SPC currently has a slight risk for severe wx for the entire cwa w/ focus on eastern/northern areas ahead and north of low where best moisture/lift will occur...aided in part along the remnants frontal boundary. Blocking h5 ridge over the eastern portion of the country will stall the exit of this system...allowing for wrap-around moisture to keep chances for trw/rw into Friday before tapering off. For temps...looking for mainly near to above normal numbers for the extended period with mainly mid to upper 70s for daytime highs. Some locales in eastern/southeastern zones could reach the lower 80s. The slow passage of the upper low Thursday/Friday will provide enough caa into nw zones to keep upper 60s for some areas. Overnight lowswill range in the 50s with some upper 40s in ne Colorado. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1100 PM MDT Tue May 24 2016 For KGLD...vfr conditions expected through 8z with winds from the southeast at 10 mph quickly shifting to the southwest. From 9z through 14z stratus expected with visibilities possibly down to 2sm creating mvfr conditions with winds from the west then northwest under 10 mph. Cigs improve to vfr by 15z with only a few clouds at best for the rest of the taf period. Winds expected from the north 5-10kts around 18z then back all the way around to the east-southeast for the remainder of the taf period. For KMCK...vfr conditions expected through 7z with cigs and vis lowering to mvfr/ifr range through 13z with winds light from the east. As winds switch around to the northwest cigs improve to vfr and continue through the rest of the period. Surface winds generally variable at speeds around 5kts or so. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...JN AVIATION...99
Area Forecast Discussion National Weather Service Wichita KS 615 PM CDT TUE MAY 24 2016 .SYNOPSIS... Issued at 311 PM CDT Tue May 24 2016 Water vapor imagery still shows the main upper energy back over the desert southwest with a weak impulse now lifting over western CO into NW NM. At the surface, there are a number of outflow/gravity waves south and southwest of our forecast area. The more robust one stretches from nw of KOKC to near KGCK with a more subtle one extending from KEND to near KDDC. A storm have developed on the boundary over north central OK and is now diving southeast. && .SHORT TERM...(This evening through Friday night) Issued at 311 PM CDT Tue May 24 2016 Confidence is high that surface based storms will develop near the intersection of the dryline and outflow after 4pm which will be over SW KS/OK panhandle. This activity will slowly migrate east this evening and may grow upscale as 850-700mb theta-e advection ramps up. How far east surface based storms make it and where additional elevated convection form is very uncertain. It`s not out of the question that the surface based storms die off as they approach western flank of forecast area as elevated storms develop near or north of I-70 later. For now, the general theme of higher severe chances generally west of I-135 looks good for tonight, with low confidence in how far east the more robust convection makes it. Weak upper energy will track of the central/northern Rockies for Wed and will push the better moisture east, generally east of I-135. The big question for storms Wed afternoon/evening will be whether there will be enough surface convergence to get storms to develop as the dryline washes out and becomes much less defined. While the better surface convergence remains down in OK Wed, will linger some small pops in case a storm or two can develop Wed afternoon/early evening. If a storm can develop, it would quickly become severe with greater than 3,500J/KG of CAPE. The main vort lobe looks to lift out across the Plains for the Thu-Fri time period. By 00z Fri this feature will be over southern CO/northern NM and by 00z Sat will be out over western KS. This should allow for better areal coverage for storms late Thu afternoon/evening. At this time thinking that the dryline will setup just west of our forecast area Thu, generally from Medicine Lodge to near Hays. Storms that develop in this area would have a good chance of affecting locations along and west of I-135. With deep layer shear increasing and high instability remaining, higher end severe looks possible Thu afternoon/evening with any storms that develop along the dryline. Storms should become more numerous Fri for much of the forecast area as the upper wave starts to directly impact central/eastern KS. While severe storms will be possible with any storm Fri, upper winds will back ahead of the upper wave, reducing good directional shear above 850mb. So while the higher end severe may not be as likely, the number of storms affecting central and eastern Kansas will be higher Fri. .LONG TERM...(Saturday through Tuesday) Issued at 311 PM CDT Tue May 24 2016 By 12z Sat there is good agreement between the GFS and ECMWF that the upper wave will be lifting over northeast KS, pushing the better convective chances northeast of the forecast area. However, we quickly get back into SW flow aloft, albeit weak. This will allow the better low level moisture to lift back across the central Plains. What makes it tough through these extended periods is the lack of a surface focus or distinct upper wave to focus on. In addition, upper winds will be considerably weaker than the current sw flow pattern we are in. So, with plenty of instability it will not take much to get a storm to develop. Have a slight lean toward the better storm chances being at night with low level jet processes helping initiate storms. Confidence is high that temps will be close to or slightly above seasonal normals through this extended period. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 616 PM CDT Tue May 24 2016 A moist southeast surface flow will continue across the area with MVFR CIGS expected to develop overnight into early Wednesday morning. Scattered strong to severe convection over northern Oklahoma and western Kansas may affect some locations west of the Kansas turnpike late this evening with potential for scattered strong storms overnight across much of the area. KED && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 68 87 69 86 / 40 20 10 30 Hutchinson 66 88 67 85 / 40 10 10 30 Newton 67 87 68 85 / 40 20 10 30 ElDorado 67 87 70 85 / 40 20 20 30 Winfield-KWLD 68 87 71 85 / 40 20 10 30 Russell 63 87 59 86 / 60 10 10 40 Great Bend 64 88 60 87 / 60 10 10 30 Salina 64 88 66 88 / 40 20 20 30 McPherson 65 88 67 85 / 40 20 10 30 Coffeyville 68 84 71 85 / 40 30 20 20 Chanute 68 84 71 85 / 40 30 20 20 Iola 67 84 70 85 / 40 30 20 20 Parsons-KPPF 68 84 71 85 / 40 30 20 20 && .ICT Watches/Warnings/Advisories...None. && $$ SHORT TERM...RBL LONG TERM...RBL AVIATION...KED
Area Forecast Discussion National Weather Service Goodland KS 505 PM MDT TUE MAY 24 2016 .SHORT TERM...(Today through Thursday night) Issued at 249 AM MDT Tue May 24 2016 Due to current ongoing storms and severe weather will wait to issue the morning forecast until severe watch 202 is cancelled. Southwest flow will persist across the central plains from today through Thursday night. A surface trough will exist over eastern Colorado today and tonight. The trough will move into northwest Kansas Wednesday and Wednesday night and then align itself along the Colorado/Kansas border Thursday night. a shortwave is advertised to come through the flow this afternoon and evening. The surface wind field suggests convergence to support thunderstorm initiation across the northern fa. There is good instability and shear to produce severe thunderstorms. Subsidence moves into the fa Wednesdays morning behind the exiting shortwave. Even through there is an apparent weak disturbance in the flow WEDNESDAY afternoon, dynamics and instability are weak so will make pops nil until late evening when some lift is shown mainly across the far north fa. Subsidence follows Thursday morning so pops will be nil. A strong shortwave comes into the area Thursday afternoon and night. Good dynamics with this feature warrant higher chance pops. Max temperatures today through Thursday should range from the upper 70s in eastern Colorado to the lower 80s across northwest Kansas. Min temperatures tonight should cool to the 50s. .LONG TERM...(Wednesday night through Tuesday) Issued at 146 PM MDT Tue May 24 2016 Going into Wednesday night...weak surface low out over the Central Plains ahead of slow moving upper low/trough over the Rockies...will combine with a boundary over the Kansas/Nebraska border to bring some light rw/trw activity to mainly northern areas thru the overnight period. By Thursday as upper trough/low begins to shift eastward into the plains and exits the area slowly by late Friday. some mid level ridging will allow for periods of dry conditions going into the first half of the weekend...do expect increase in areal coverage of rw/trw late Saturday night on through the beginning of next week as a couple of shortwave move around the base of approaching upper low from the Pacific NW/Northern Rockies. The entire Tri State region will have chances for trw/rw for much of the extended period. Lowest probability will occur on Saturday as weak ridging occurs. Best chances for precip will occur Thursday and Thursday night with the arrival of the enhanced dynamics of the upper low combining with remnants of surface low/frontal boundary. SPC currently has a slight risk for severe wx for the entire cwa w/ focus on eastern/northern areas ahead and north of low where best moisture/lift will occur...aided in part along the remnants frontal boundary. Blocking h5 ridge over the eastern portion of the country will stall the exit of this system...allowing for wrap-around moisture to keep chances for trw/rw into Friday before tapering off. For temps...looking for mainly near to above normal numbers for the extended period with mainly mid to upper 70s for daytime highs. Some locales in eastern/southeastern zones could reach the lower 80s. The slow passage of the upper low Thursday/Friday will provide enough caa into nw zones to keep upper 60s for some areas. Overnight lowswill range in the 50s with some upper 40s in ne Colorado. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 500 PM MDT Tue May 24 2016 KGLD...currently expecting vfr conditions through the period. Am concerned about model boundary layer moisture that at present time is overdone with forecast ceilings. This moisture ramps up early to mid evening and continues through the early morning hours before lifting northeast away from the terminal. Have scattered clouds around 400` as a start and will watch closely. Winds begin the period from the southeast around 11-12kts with some gusts then shift to the southwest under 10kts around 8z. Winds continue to veer around to the west and northwest near 10kts from 9z to 18z then back to the southwest around 7kts from 19z through the rest of the taf period. KMCK...similar to KGLD am concerned about models handling of low level moisture and possibility that cigs wont be as low as they suggest. Otherwise am expecting thunderstorms around/over the terminal from 6z through about 11z. Vfr cigs at taf issuance expected to decrease to ifr/vlifr range by 6z and continue through 16z. after 17z drier air moves in from the southwest allowing vfr conditions to return through the rest of the taf period. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...JN AVIATION...99
Area Forecast Discussion National Weather Service Goodland KS 1202 PM MDT TUE MAY 24 2016 .SHORT TERM...(Today through Thursday night) Issued at 249 AM MDT Tue May 24 2016 Due to current ongoing storms and severe weather will wait to issue the morning forecast until severe watch 202 is cancelled. Southwest flow will persist across the central plains from today through Thursday night. A surface trough will exist over eastern Colorado today and tonight. The trough will move into northwest Kansas Wednesday and Wednesday night and then align itself along the Colorado/Kansas border Thursday night. a shortwave is advertised to come through the flow this afternoon and evening. The surface wind field suggests convergence to support thunderstorm initiation across the northern fa. There is good instability and shear to produce severe thunderstorms. Subsidence moves into the fa Wednesdays morning behind the exiting shortwave. Even through there is an apparent weak disturbance in the flow WEDNESDAY afternoon, dynamics and instability are weak so will make pops nil until late evening when some lift is shown mainly across the far north fa. Subsidence follows Thursday morning so pops will be nil. A strong shortwave comes into the area Thursday afternoon and night. Good dynamics with this feature warrant higher chance pops. Max temperatures today through Thursday should range from the upper 70s in eastern Colorado to the lower 80s across northwest Kansas. Min temperatures tonight should cool to the 50s. .LONG TERM...(Friday through Monday) Issued at 249 AM MDT Tue May 24 2016 Heading into the weekend a meandering surface boundary sets up over the Central Plains out ahead of a upper level trough over the Rockies. Models show this system shifting eastward of the region Friday night, before lifting into North Central Nebraska. Potential for showers and thunderstorms increases over the holiday weekend as remnants from the prior boundary looks to remain over the region and another upper level low moving through the North Central Rockies. Look for much the same at the beginning of the work week as another system looks to move through the region. With a general southwesterly upper flow over the region, look for near to above normal temperatures through the extended as decent warm air advection over the area. Daytime highs will range from the mid 70s thru the mid 80s. Overnight lows will range from the upper 40s thru the mid 50s. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1202 AM MDT Tue May 24 2016 MVFR stratocu slowly breaking up and lifting at KGLD. Expecting marginally VFR conditions to take hold shortly. Afternoon thunderstorms will develop once again today. Anticipating development along a remnant outflow boundary over southwest Kansas with storms moving northeast into northwest Kansas. This area of storms could impact KGLD but anticipate most activity to remain southeast. Therefore, only mentioned VCTS for KGLD. Another area of storms will develop near the Denver Metro, spreading east through the evening. It is this area of storms that are most likely to impact KMCK. A late evening arrival seems most probable from latest suite of guidance. Late tonight, LLWS may develop as a low level jet strengthens. Remain a little unsure on the timing and height of the LLWS so for now did not input LLWS into the TAF. Stratus/fog development is forecast along a boundary over northeast Colorado. This deserves a watchful eye depending on how storms impact the boundary layer. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...BW AVIATION...RRH
Area Forecast Discussion National Weather Service Wichita KS 1207 PM CDT TUE MAY 24 2016 .SHORT TERM...(Today through Thursday night) Issued at 355 AM CDT Tue May 24 2016 Forecast Highlight: Sever thunderstorm potential increasing for much of South-Central KS along & W of I-35/I-135 late this afternoon & Evening. Today & Tonight: Numerous strong & severe thunderstorms continue to occur across Nrn KS in pronounced E/W-oriented convergent axis no doubt enhanced by moisture-rich low-level jet/convective outflow interaction. Still expect convection to s-l-o-w-l-y wane this morning as low-level jet weakens. Attention shifts to this afternoon & evening, most notably South-Central KS along & W of I-35/I-135. A mid-level shortwave is still expected to strengthen considerably as it lifts ne from Ern NM across the TX Panhandle this afternoon and reaching SW KS early this evening. With high octane fuel continuing to stream N across KS & the approaching shortwave inducing pronounced deep shear, both speed & directional (more so directional) severe thunderstorms are scheduled to develop from Ern parts of the TX & OK Panhandles to SW & SC KS late this afternoon & evening. SPC has assigned an enhanced risk for severe thunderstorms for these areas which clearly makes sense. CAPES are extremely high & although the GFS may be getting a a CAPE adrenaline rush by projecting MLCAPES venturing into 5000 to 6000J/KG country there`s no doubt the airmass will be VERY unstable. This warrants a "Severe Thunderstorms with Large Hail and Damaging Wind" assignment to SC KS along & W of I-35/I-135. There`s also an increasing potential for a few tornadoes for these areas during these periods. Stay tuned. Wed-Thu Night: The afore-mentioned mid-level shortwave will shear as it sprints NE toward, then across, the Mid-MS Valley Wed Afternoon & Evening, but a 2nd & stronger mid-upper shortwave is scheduled to surge SE from the Nrn Rockies. This character will likely induce mid-level cyclogenesis over AZ & NM Wed Night. As the strong mid-upper wave pushes ENE toward the Front Range deep-scale ascent will increase & also find rich moisture with which to interact. As such more severe thunderstorms are very possible for the latter parts of the work-week. Wed & Wed Night appear most volatile for SE KS. .LONG TERM...(Friday through Monday) Issued at 355 AM CDT Tue May 24 2016 With mid-range models in better agreement the inherited forecast has been kept intact. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1201 PM CDT Tue May 24 2016 Main Aviation Hazards: Thunderstorm and stratus potential. Small chances for thunderstorms this afternoon near the Kansas/Oklahoma border near a west to east oriented convective outflow boundary. Any of this activity that may develop is expected to stay south of the ICT and CNU terminals through 00z. Otherwise, a better chance for scattered severe thunderstorms will be late this afternoon/evening...with development first occurring in western Kansas into northwestern Oklahoma. These storms will have an eastward motion and could reach around the I-135 corridor toward mid-late evening. Highest probabilities initially will be at the RSL and GBD terminals where a tempo +TSRA is planned early this eve, and will use VCTS as far east as SLN and ICT Terminals. Strong-severe outflow wind gusts and potentially large hail could accompany this storm activity. Southeasterly, continued moist flow should result in stratus development across much of the region late tonight into Wednesday morning. Low MVFR ceilings appear likely, with some potential for IFR. && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 80 68 86 69 / 40 40 10 10 Hutchinson 80 68 87 66 / 40 50 10 10 Newton 79 68 86 68 / 50 40 10 20 ElDorado 79 67 85 69 / 60 30 20 20 Winfield-KWLD 81 68 86 70 / 20 40 10 20 Russell 80 66 87 62 / 60 60 10 10 Great Bend 81 67 88 61 / 40 60 10 10 Salina 80 67 87 67 / 70 50 20 20 McPherson 80 68 86 66 / 50 50 10 10 Coffeyville 80 69 83 72 / 30 30 30 20 Chanute 80 68 82 72 / 50 30 30 30 Iola 80 68 82 72 / 60 30 30 30 Parsons-KPPF 79 68 83 72 / 40 30 30 30 && .ICT Watches/Warnings/Advisories... None. && $$ SHORT TERM...EPS LONG TERM...EPS AVIATION...JMC
Area Forecast Discussion National Weather Service Wichita KS 651 AM CDT TUE MAY 24 2016 .SHORT TERM...(Today through Thursday night) Issued at 355 AM CDT Tue May 24 2016 Forecast Highlight: Sever thunderstorm potential increasing for much of South-Central KS along & W of I-35/I-135 late this afternoon & Evening. Today & Tonight: Numerous strong & severe thunderstorms continue to occur across Nrn KS in pronounced E/W-oriented convergent axis no doubt enhanced by moisture-rich low-level jet/convective outflow interaction. Still expect convection to s-l-o-w-l-y wane this morning as low-level jet weakens. Attention shifts to this afternoon & evening, most notably South-Central KS along & W of I-35/I-135. A mid-level shortwave is still expected to strengthen considerably as it lifts ne from Ern NM across the TX Panhandle this afternoon and reaching SW KS early this evening. With high octane fuel continuing to stream N across KS & the approaching shortwave inducing pronounced deep shear, both speed & directional (more so directional) severe thunderstorms are scheduled to develop from Ern parts of the TX & OK Panhandles to SW & SC KS late this afternoon & evening. SPC has assigned an enhanced risk for severe thunderstorms for these areas which clearly makes sense. CAPES are extremely high & although the GFS may be getting a a CAPE adrenaline rush by projecting MLCAPES venturing into 5000 to 6000J/KG country there`s no doubt the airmass will be VERY unstable. This warrants a "Severe Thunderstorms with Large Hail and Damaging Wind" assignment to SC KS along & W of I-35/I-135. There`s also an increasing potential for a few tornadoes for these areas during these periods. Stay tuned. Wed-Thu Night: The afore-mentioned mid-level shortwave will shear as it sprints NE toward, then across, the Mid-MS Valley Wed Afternoon & Evening, but a 2nd & stronger mid-upper shortwave is scheduled to surge SE from the Nrn Rockies. This character will likely induce mid-level cyclogenesis over AZ & NM Wed Night. As the strong mid-upper wave pushes ENE toward the Front Range deep-scale ascent will increase & also find rich moisture with which to interact. As such more severe thunderstorms are very possible for the latter parts of the work-week. Wed & Wed Night appear most volatile for SE KS. .LONG TERM...(Friday through Monday) Issued at 355 AM CDT Tue May 24 2016 With mid-range models in better agreement the inherited forecast has been kept intact. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 650 AM CDT Tue May 24 2016 Expect MVFR CIGS for most locations this morning as low-mid level moisture remains high. A cluster of storms currently over Central KS near the KRSL and KSLN tafs will slowly move E-SE during the morning hours. So will go with a tempo group for the KSLN TAF for this chance. Also a little further to the south-southeast, an outflow boundary continues to drop south into South Central KS. This outflow will shift winds around to the E-NE for the KHUT, and KICT TAFS for a few hours this morning. As the outflow moves south, lift created by the outflow may lead to the redevelopment of additional SHRA/TSRA for the KICT, KHUT and KCNU TAFs. So will keep a VCTS in for this chance for the morning hours. Attention will then shift to the late afternoon/evening hours, as a dryline is expected to be just west of KGBD and KRSL. Severe TSRA is expected to develop along this boundary just to the west of KGBD and KRSL by this evening. Could also see some of the TSRA move NE and possibly reach KHUT as well, so will include the mention of VCTS for KGBD, KRSL and KHUT for the evening hours. Not as confident in TSRA but will go ahead and go with a VCTs for KICT as well. Ketcham && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 82 68 86 69 / 60 60 10 10 Hutchinson 83 68 87 66 / 50 60 10 10 Newton 82 68 86 68 / 60 60 10 20 ElDorado 81 67 85 69 / 60 60 20 20 Winfield-KWLD 81 68 86 70 / 60 60 10 20 Russell 83 66 87 62 / 60 50 10 10 Great Bend 84 67 88 61 / 50 50 10 10 Salina 82 67 87 67 / 60 60 20 20 McPherson 82 68 86 66 / 50 60 10 10 Coffeyville 80 69 83 72 / 60 40 30 20 Chanute 81 68 82 72 / 60 40 30 30 Iola 81 68 82 72 / 60 40 30 30 Parsons-KPPF 81 68 83 72 / 60 40 30 30 && .ICT Watches/Warnings/Advisories... None. && $$ SHORT TERM...EPS LONG TERM...EPS AVIATION...Ketcham
Area Forecast Discussion National Weather Service Dodge City KS 418 AM CDT TUE MAY 24 2016 ...Updated Short Term and Long Term Sections... .SHORT TERM...(Today and tonight) Issued at 415 AM CDT Tue May 24 2016 There is a lot of uncertainty in the mesoscale details of the forecast today. The big convective cluster that has been nearly stationary since midnight in northern Kansas still had not developed enough of a cold pool to organize into a forward propagating MCS as of 09Z. Most of the short term convective allowing models suggest that the cluster will begin propagating southeast during the early morning hours with outflow spreading back west of Dodge City by late morning. A subtle upper level trough that appears in WV imagery in central New Mexico should propagate into western Kansas by early afternoon. A surface cyclone in southeast Colorado should remain nearly stationary, and the models suggest that a dryline will mix east into southwest Kansas and may reach a line from Garden City to Liberal by mid afternoon. A subsynoptic cyclone likely will exist near the intersection of the old outflow boundary with the dryline somewhere near Dodge City late this afternoon. Extremely moist air will continue to flow into western Kansas, and the mid level warm pool will keep convection from firing until late afternoon. Convergence along the old outflow boundary and the dryline with afternoon heating and some marginal upper level divergence with the weak upper level trough should be sufficient to initiate thunderstorms. Although high level flow is not terribly strong, 30-35 knot shear from surface to 6 km should support rotating updrafts. As such, a few supercells are likely late this afternoon before the thunderstorms organize upscale into a MCS that will propagate across southern Kansas during the evening hours. A tornado is possible where low level shear is maximized near the intersection of the outflow boundary and the dryline. The vigorous upper level trough evident on satellite imagery over California early this morning should eject rapidly northeast as the next trough rotating around the gyre in the western United States drops southeast from near 40N/130W into southern California by Wednesday morning. The trough currently over California should reach the Dakotas by Wednesday morning, and falling pressures in the northern Plains will veer the low level flow in western Kansas Tuesday night and Wednesday. The deep moisture should be scoured out of western Kansas on Wednesday, and temperatures likely will warm to near 90 with H8 temperatures in the mid 20C range. The potential for thunderstorms Wednesday is minimal. .LONG TERM...(Wednesday through Monday) Issued at 415 AM CDT Tue May 24 2016 An active flow regime will continue with a mean long wave trough in the western United States and ridging in the eastern part of the country through early June. Minor waves will continue to ripple through the southwest flow aloft and provide opportunities for thunderstorm development nearly every day. The upper level cyclone that digs into California Wednesday will move into eastern Colorado by Friday morning. Surface cyclogenesis will occur in eastern Colorado Thursday afternoon, and low level moisture should surge back into southwest Kansas by Thursday afternoon. Another round of thunderstorms is likely Thursday afternoon near and east of the dryline position and near a weak stationary front across northern Kansas. A Pacific cold front will move into western Kansas Friday, and additional thunderstorm development can be expected under the cold pool with the upper level cyclone. Saturday probably will be quiet, but another minor wave in the southwest flow will approach the Central Plains on Sunday. Yet another minor wave should approach Kansas Monday afternoon. Temperatures will be above seasonal averages with highs in the 80s and lows in the 50s and lower 60s through the week. There is little indication that a strong subtropical high will build into the Plains through at least mid June, although there may be a brief period of anticyclogenesis in the central part of the country around 9-11 June. An active flow regime characterized by a mean trough in the western United States and ridging in the eastern part of the country appears to be the base state of the atmosphere for the foreseeable future. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 121 AM CDT Tue May 24 2016 A weak stationary front extending from eastern Nebraska across northwest Kansas into a surface low in eastern Colorado will move little today. A cluster of thunderstorms at the nose of the low level jet in northern Kansas will propagate to the east-southeast and should be east of HYS by 11Z. Patchy stratus with bases 010-020 will become widespread by 09z and persist through the early morning hours. Visibilities may be restricted to 3-5SM in mist around sunrise. The stratus should erode during the morning hours to sct to bkn030-040 by 18Z. Low level winds generally will be from the south-southeast at 15-20 kts but will be variable and gusty near the thunderstorm cluster in northern Kansas. A dryline will mix east to near DDC this afternoon, and severe thunderstorms are likely to develop near DDC around 21Z and spread east into central Kansas during the evening hours. Low level winds will veer above the surface Tuesday night, and Tuesday night may be free of stratus. && .PRELIMINARY POINT TEMPS/POPS... DDC 84 61 89 56 / 50 50 10 0 GCK 85 58 89 53 / 10 10 10 0 EHA 88 55 88 53 / 0 0 0 0 LBL 88 56 91 54 / 20 10 0 0 HYS 80 62 88 57 / 50 30 10 10 P28 84 65 91 66 / 40 50 10 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Ruthi LONG TERM...Ruthi AVIATION...Ruthi
Area Forecast Discussion National Weather Service Dodge City KS 123 AM CDT TUE MAY 24 2016 ...Updated Aviation Section... .SHORT TERM...(This evening through Tuesday) Issued at 130 PM CDT Mon May 23 2016 Dependent on the time frame for air mass recovery from yesterday`s convection across the high plains southward into the panhandle of Texas, thunderstorms will be possible across central and portions of southwest Kansas tonight into Tuesday as short range models indicate a difluent southwest flow aloft prevailing across the Central Plains. The RAP13 and HRRR initialize well with the surface low in extreme southwest Kansas and an attendant frontal boundary extending northeast into north central Kansas and showing both lifting northward across western Kansas through this evening. A southeasterly upslope flow will redevelop across central and much of southwest Kansas as a result, and in turn, draw moisture back to the north raising surface dewpoints up into the lower and mid 60s(F) across central and much of southwest Kansas. Heating of the lower/mid levels will increase this afternoon as the prevailing lower cloud deck continues to slowly scatter out, allowing lower/mid level lapse rates to steepen. Depending on how long this takes, thunderstorms will be possible toward early evening as the cap weakens with the best chance for convection associated with the frontal boundary as it lifts north. Short fuse model soundings show SBCAPE values climbing in excess of 4000 J/KG across south central and eastern southwest Kansas through early this evening, increasing severe potential. Based on the substantially high amount of CAPE, large hail will be the primary threat with damaging winds also possible. Due to a modest amount of vertical shear present, an isolated tornado threat closer to the Oklahoma border does exist. A few isolated storms may develop across eastern Colorado within an upslope flow and move into west central Kansas later tonight as an H5 vort maxima kicks northeast out of the Southern Rockies into the Western High Plains. However, with less instability available, the potential for severe storms will be limited with damaging winds the main threat. A prevailing low level south to southeasterly flow across western Kansas tonight will help reinforce a moisture pool across the area with surface dewpoints remaining in the upper 50s(F) to the mid 60s(F). Look for lows generally in the 60s(F) toward daybreak Tuesday with a few upper 50s(F) possible in west central Kansas. For Tuesday, warm air advection across the high plains will push H85 temperatures well up into the mid to upper 20s(C) across southwest and much of central Kansas. Widespread 80s(F) can be expected for highs Tuesday afternoon with near 90F possible in extreme southwest Kansas. .LONG TERM...(Tuesday night through Monday) Issued at 235 PM CDT Mon May 23 2016 Thunderstorms will be possible across central and portions of southwest Kansas Tuesday evening as medium range models show another in a series of H5 vort maxima ejecting out of the Southern Rockies into the high plains of western Kansas. Although the flow aloft will remain fairly weak, considerable moisture and instability will be present to support thunderstorm development along and ahead of a dryline projected to extend southward across southwest Kansas off of an advancing surface low out of eastern Colorado. Significant instability will heighten the potential for severe storms, particularly across central Kansas. The focus for precip shifts eastward Wednesday as drier air lifts northeast into southwest Kansas behind a dryline expected to push a little eastward across the area. Prevailing southerlies near the surface will reinforce the warmer air mass across the high plains Wednesday and Thursday. Highs mainly up into the 80s(F) can be expected each day with a few lower 90s(F) possible in some locations. Cooler temperatures are expected by Friday with a cold front pushing through western Kansas toward the end of the week. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 121 AM CDT Tue May 24 2016 A weak stationary front extending from eastern Nebraska across northwest Kansas into a surface low in eastern Colorado will move little today. A cluster of thunderstorms at the nose of the low level jet in northern Kansas will propagate to the east-southeast and should be east of HYS by 11Z. Patchy stratus with bases 010-020 will become widespread by 09z and persist through the early morning hours. Visibilities may be restricted to 3-5SM in mist around sunrise. The stratus should erode during the morning hours to sct to bkn030-040 by 18Z. Low level winds generally will be from the south-southeast at 15-20 kts but will be variable and gusty near the thunderstorm cluster in northern Kansas. A dryline will mix east to near DDC this afternoon, and severe thunderstorms are likely to develop near DDC around 21Z and spread east into central Kansas during the evening hours. Low level winds will veer above the surface Tuesday night, and Tuesday night may be free of stratus. && .PRELIMINARY POINT TEMPS/POPS... DDC 63 87 64 89 / 30 20 20 10 GCK 58 87 60 89 / 20 10 10 10 EHA 58 90 57 88 / 10 10 10 0 LBL 62 90 62 91 / 20 10 10 0 HYS 60 84 63 88 / 40 20 20 10 P28 67 86 67 91 / 50 30 30 10 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...JJohnson LONG TERM...JJohnson AVIATION...Ruthi Area Forecast Discussion National Weather Service Taunton MA 1026 AM EDT WED MAY 25 2016 .SYNOPSIS... An upper level ridge will bring very warm weather to most of the region through Saturday, except for cooler temperatures at times along the immediate coast. A backdoor cold front will bring cooler weather to the region sometime on Sunday, but temperatures should rebound to at or above normal by early next week. A few showers and thunderstorms are possible Thursday night into Friday, and again this weekend but the vast majority of this time will be dry. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ***Summer temperatures push in today across the region*** 1030 AM Update...Most of the fog has cleared out across the area with the exception of one band of fog that is hugging the south coast of RI and moving eastward towards Buzzards Bay and the Cape. If it continues on this trajectory without burning off, portions of Cape Cod along the Cape Cod Canal as well as Martha`s Vineyard and the Elizabeth Islands will see a period of fog later this morning into early afternoon. Visibilities have been generally about a mile with this bank of fog on land, it may be more dense over the water. Made minor adjustments to the temperatures to ease them back as they have not jumped up as quickly as forecast. Otherwise, the previous forecast is on track. Weak ridging at the surface and aloft will cross the region by midday through the afternoon with NW winds aloft. Warm core H925 temps will push across the region, up to +19C to +22C by this afternoon. Once skies become mostly sunny, temps will rise quickly with excellent low and mid level mixing in place. Expect temps to top off in the mid-upper 80s with a few spots touching 90. However, dewpoints falling into the 40s will result in low humidity levels. High clouds will start to push in from the NW during the mid and late afternoon ahead of H5 short wave across far northern New England. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Tonight... Most of the energy from a weak H5 shortwave trough will remain across northern New England. NW flow keeps dry conditions across the region tonight. The mid and upper level clouds will dissipate overnight as SW winds shift back to W-NW and diminish. It will remain mild, with temperatures only bottoming out from the mid 50s well inland to lower-mid 60s across the coastal plain. Thursday... A cold front will slowly push S across the region during the day. Clouds will push in from the W as the front moves in during the afternoon. Short range models vary in their solutions, with mainly dry conditions through the day offered by the ECMWF, but the GFS tends to bring some moisture with a weak H5 shortwave in the W-NW flow aloft. Have mentioned only slight chance PoPs moving into W MA/N Central CT during the mid and late afternoon hours. Have noted marginal instability with this system, plus another day of warm temperatures, so have mentioned widely scattered showers/isolated thunderstorms. It will be another warm day, with somewhat higher dewpoints making it feel a bit more humid. Highs will again be in the mid-upper 80s away from the immediate coast, with a few spots possibly hitting 90 again. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Highlights... * Friday: Very warm w/highs mid-upper 80s northwest of BOS-PVD but a bit cooler across southeast MA/RI * Saturday: Hot and a bit humid w/highs mainly upper 80s to lower 90s away from the immediate south coast * Sunday: Temps uncertain depending on timing of cold front, warmest readings likely CT River Valley w/coolest across Eastern MA coast * A few showers/t-storms possible Thu night/Fri and again Sat/Sun but the vast majority of this time will be dry * At or above normal temperatures likely return early next week Details... Thursday night...Shortwave energy and a burst of elevated instability may result in a few showers/t-storms Thursday night, mainly northwest of a Boston to Providence line. If any activity is able to develop, it will be short-lived with the majority of the night ending up dry. Low temps mainly in the upper 50s to the lower 60s. May see some patchy ground fog develop late in the typically prone locations. Friday...Surface winds shift to the south-southwest behind the warm front as 850T rise to around +14C. Plenty of sunshine should allow highs to warm into the middle to upper 80s northwest of a Boston to Providence line. Southeast of this line...a cooling marine layer may hold highs in the upper 70s to the lower 80s. Dry weather will dominate on Friday, but enough instability combined with a pre-frontal trough may allow a few showers/thunderstorms to develop across W MA/N CT Fri afternoon and evening. Not sure if this activity gets into our region or stays to our west, but highest risk will be across northwest MA. Shear is rather weak so even if we see a few thunderstorms in our western zones, overall severe weather threat is rather low. Saturday...A hot and somewhat humid day is on tap to kick off the Memorial Day Weekend. 850T around +16C, plenty of sunshine, and a westerly component to the surface winds should allow for high temps to reach into the upper 80s to the lower 90s away from the immediate south coast. Dewpoints between 60 and 65 across most of the region will make it feel a bit humid. While most of the day will be dry, a few showers and thunderstorms may develop Saturday afternoon and evening with a pre-frontal trough and CAPE values between 1000 and 2000 J/KG. This will be mainly to the northwest of a Boston to Providence line. Forcing will be rather weak, so areal coverage of any activity that develops may remain limited. Severe weather threat also looks rather low at this time with rather weak 0 to 6 km shear, but too early to rule out a strong thunderstorm or two given decent instability. Sunday...Low confidence on high temperatures given a subtle change in timing of the backdoor cold front will make a big difference in the exact outcome. We can say that the warmest readings will be across the lower CT River Valley and coolest along the eastern MA coast. Good shot though at the CT River Valley seeing high temps reaching well into the 80s, while the eastern MA coast has afternoon temps falling into the 60s. A few showers will remain possible and perhaps even a couple of t-storms across the interior if enough instability develops during the afternoon. Monday and Tuesday...Backdoor cold front does not appear as strong on the latest model runs. It looks to washout across the region early next week. GFS washes out on Monday while the ECMWF waits until Tuesday. Probably should see the return to above normal temps by Tue with rather warm temps aloft. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Today...High confidence. VFR conditions expected the rest of the day, except on the Cape and Islands where fog may reduce visibilities down to MVFR/IFR at times. Tonight...High confidence. VFR conditions. W-NW winds 10 kt or less. Thursday...High confidence. VFR. Light W-NW winds, except sea breezes possible late morning/afternoon along the coast. KBOS TAF...Moderate to high confidence. An ESE sea breeze has developed and is expected to continue into early afternoon. Southwesterly winds should overcome this by late afternoon. KBDL TAF...High confidence in TAF. Outlook /Thursday Night through Sunday/... Thursday night and Friday...Moderate to high confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few brief showers/t-storms mainly across the interior. Also, some patchy ground fog possible in the typically prone locations very early Fri AM. Saturday...Moderate to high confidence. VFR conditions likely dominate but a brief period of MVFR-IFR cigs/vsbys possible in a few afternoon and evening showers/thunderstorms. Sunday...Low confidence. MVFR-IFR conditions may develop from east to west behind a backdoor cold front. A few thunderstorms also possible Sun afternoon across the interior. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Today...High confidence. W winds up to 10 kt will back to SW 10-15 kt this afternoon with gusts up to 20 kt on the southern outer waters. Seas 4 ft or less. Patchy fog mainly along the south coast will result in reduced visibilities at times. Tonight...High confidence. Light southwesterly winds become westerly, gusting up to 20 kt on the southern outer waters this evening. Seas 4 ft or less. Thursday...High confidence. Light W winds shifting to S in the afternoon. Seas remain below 5 ft. Outlook /Thursday Night through Sunday/...High Confidence. Winds and seas will generally remain below Small Craft Advisory thresholds through the period. The main concerns are a period of near-shore southwesterly wind gusts of 20 to 25 knots Saturday afternoon which will result in some choppy seas for mariners. May also see some brief easterly wind gusts between 20 and 25 knots on Sunday behind a backdoor cold front. && .FIRE WEATHER... Today...Expect temperatures will rise quickly, soaring well into the 80s to near 90 across most locations except cooler along the immediate south coast. These temperatures will combine with dewpoints dropping into the 40s resulting in afternoon RH values down to between 20 and 30 percent. A few hours of westerly wind gusts up to 20 to perhaps briefly 25 mph are anticipated. Given Tuesday`s rainfall and marginal criteria, will fall short of needing fire weather headlines. Many locations are close to or already at full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert until 11 PM EDT this evening for MAZ020>024. RI...Air Quality Alert until 11 PM EDT this evening for RIZ003-004- 006>008. MARINE...None. && $$ SYNOPSIS...Frank/EVT NEAR TERM...Frank/RLG/EVT SHORT TERM...EVT LONG TERM...Frank AVIATION...Frank/EVT MARINE...Frank/EVT FIRE WEATHER...Staff
Area Forecast Discussion National Weather Service Taunton MA 229 AM EDT WED MAY 25 2016 .SYNOPSIS... A few leftover showers may fall across western MA and north central Conn., as well as south coastal MA and RI through the early this morning as low pressure slowly moves northeast to the Gulf of Maine. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 145 AM Update... H5 cutoff low has pushed just E of Cape Cod as seen on latest water vapor and IR satellite imagery. Winds have diminished to near calm away from the coast at 05Z obs. Noting patchy dense fog has started to form across portions of the CT valley into NE CT. May see more develop over the next few hours across central and western areas. May also see a few showers develop with the last of the band crossing out the Berkshires through 08Z-09Z. Remainder of previous forecast in pretty good shape, but have updated to bring current. Previous discussion... With light winds across the region, along with lowering temp/dewpoint spreads, will still see patchy fog develop along with lingering low clouds from around Worcester and Windham counties eastward through around midnight, but trends continue to indicate that this should slowly push E during the early morning hours as the low exits, but will be slowest across E coastal MA. Partial clearing should begin moving into the CT valley after midnight as winds back to light NW, then will slowly shift E overnight. Clouds will linger along the E coast through daybreak. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/... *** Summer-like Temperatures Move in Today *** Today ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through 12Z...Moderate confidence, though lower in timing of improving conditions toward daybreak. Areas of IFR-LIFR CIGS and mixture of VFR to IFR VSBYS in patchy fog, lowest across interior E MA and portions of CT valley into NE CT. Should start to see conditions improve to VFR across CT valley after 08Z, then slowly progressing E after daybreak. Calm or light/vrbl winds. Today...Moderate confidence this morning, then high confidence. IFR CIGS and areas of MVFR-IFR VSBYS across central-E MA/RI should improve by mid morning. Otherwise, VFR. W-SW winds 10 kt or less. Tonight...High confidence. VFR conditions. W-NW winds less than 10 kt. Thursday...High confidence. VFR. Light W-NW winds, except sea breezes possible late morning/afternoon along the coast. KBOS TAF...Moderate confidence. Uncertain on exact timing of improvement, but should take place by around 10Z. KBDL TAF...Moderate confidence. otherwise VFR. Outlook /Thursday Night through Sunday/... Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through 12Z...High confidence. Upper level low will slowly move into Massachusetts Bay during the early morning hours. Light E-NE winds across the eastern waters will back to N-NW, becoming mainly W of all waters toward daybreak. Leftover SE swells will linger on the outer waters E and S of Cape Cod, but should subside below 5 ft by around 08Z- 09Z. Visibility restrictions in patchy fog, locally dense in some locations, should improve from W-E. Today...High confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Tonight...High confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday Night through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... Wednesday...High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given today`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for MAZ020>024. RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for RIZ003-004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT early this morning for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...EVT SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Dunten/EVT MARINE...Nocera/Dunten/EVT FIRE WEATHER...Staff
  [top] Area Forecast Discussion National Weather Service Albany NY 210 AM EDT WED MAY 25 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... As of 210 AM EDT...showers have dissipated across all of our region, and so have many of the clouds. However, as moisture pooled from the Hudson valley eastward, patchy dense fog was beginning to form from the Hudson valley eastward with dewpoints still around 50 or higher, compared to much lower levels just west, where they were from the upper 30s to mid 40s. At this time of night, with decoupling, there really is no way for these dewpoints to advect further east, so we don`t expect much in them overnight. We did however, lower some places a couple of degrees. Look for lows generally 45-50 with light or calm wind. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... It looks as if we will dealing with quite a bit of IFR flying conditions through 11Z thanks to residual low level moisture trapped in the Hudson valley and Berkshires. This despite our local Fog study program did not forecast any fog in any of the TAFs. As of 06Z Low IFR was already reported at KGFL and KPSF. While KALB was still VFR their remarks indicated patches of fog (BCFG) so we believe they too will have at least temporary times of IFR. KPOU looks to have some IFR fog although studies have indicated it is hard to fog at the site. Any and all fog will be gone before 12Z leaving us to a VFR flying day as dry air will mix down as a breeze kicks in from the west, 5- 10KTS, gusting to 20KTS by midday at KPSF and KALB. After 12Z clouds will be few-sct with some cumulus around 5 KFT and a few higher clouds at times. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...HWJIV/BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...HWJIV/BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS
  [top] Area Forecast Discussion National Weather Service New York NY 959 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure departs to the northeast as high pressure builds to the south on Wednesday. A cold front moves through on Thursday. High pressure will then dominate through Saturday night as a series of weak upper level disturbances move across. A cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. persistent showers continue to track down from new england...so have added chc pops for a few more hours as a weakening trend is noted on radar as well as in the hrrr. dry weather should return by midnight with decreasing clouds overnight. have also added patchy fog to ct coastal areas and ern long island overnight with light winds and high moisture content at the sfc. Otherwise...minor adjustments made to hourly t/td. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. With lighter winds across the interior, min temperatures were further lowered by a degree. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south overnight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light overnight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... light pcpn amounts (less than 1/10 inch) in any remaining showers this eve. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
Area Forecast Discussion National Weather Service Albany NY 812 PM EDT TUE MAY 24 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... As of 800 PM EDT...Weak deformation axis association with scattered to broken band of showers just east of the Hudson River should continue into the evening hours. The upper low in the vicinity of Providence, RI is beginning to show signs of tracking ENE per the latest H2O loop analysis. With this movement we should see a diminishing trend in the showers which too is suggested by the HRRR. So main update was to the sky coverage, PoPs/WX, removed the mention of thunder and expanded the fog a little further west to include the Hudson River Valley overnight as skies should clear overnight under diminishing winds. Question will be just how much fog impact will occur as dewpoints upstream were between 30-40F compared to mid 50s across eastern NY. We will monitor closely. Prev disc...Upper low departing northeast slowly but steadily. Very narrow band of rain in eastern NY with some isolated thunderstorms from the Berkshires through NW CT and the mid Hudson Valley. Rain and isolated thunderstorms will build east and dissipate through the evening...and clearing will take place through the night. Quite a bit of clearing outside of the moisture field of the upper low...so by daybreak most areas should be clear to mostly clear. There could be some patchy fog as low level winds should trend to calm and areas with wet ground could support some patchy fog but with dryer surface dewpoints advecting in...it could minimize chances for fog. Only including patchy fog for areas east of the Hudson Valley into western New England where most of the rain has fallen. Lows in the mid 40s to lower 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Showers continue to impact the Hudson River Valley and points east which is mainly where our TAFs are located. Included a VCSH or a TEMPO group for the next few hours. Otherwise, VFR conditions through the evening hours. The question for tonight will be how much BR/FG form. All terminals will clear out overnight. Winds will be light but dewpoints upstream are about 10-15 degrees cooler than those observed across eastern NY and western NE. At this time, the best IFR chances for FG are at KPSF/KGFL where showers and trapped moisture near the inversion. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS www.weather.gov/albany
Area Forecast Discussion National Weather Service New York NY 737 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. High pressure will dominate through Saturday night as a series of weak upper level disturbances move across. A back door cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. Made some adjustments to pops next couple of hours based on latest radar trends. Showers continue to weaken this eve and dry weather should return by midnight. Otherwise...minor adjustments made to hourly t/td and winds. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. Also with lighter winds across the interior and residual low level moisture...there could be some patchy fog late into early Wednesday Morning. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /23Z TUESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south tonight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light tonight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: No unscheduled amendments this evening. A late day seabreeze is expected Wednesday. KLGA TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KEWR TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KTEB TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KHPN TAF Comments: Patchy fog is possible overnight. West winds will increase by afternoon with occasional gusts expected. KISP TAF Comments: No unscheduled amendments this evening. A late day seabreeze may approach the airport Wednesday, but do not expect the seabreeze to move through at this time. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected into early this evening. Locally higher amounts will be possible in thunderstorms. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
Area Forecast Discussion National Weather Service Taunton MA 703 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers will continue across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 700 PM Update... Overall forecast is on track. Removed the thunder mention for this evening as convection has remained just west of southern New England. Also increased precip trends across RI and southeast MA as area of showers continues to develop and spin as the upper level low begins to slowly shift eastward. Otherwise breaks of sun across western MA as allowed for temps to warm in to the upper 60s late this afternoon. Onshore flow across eastern MA will continue until the low shifts eastward creating more of a northerly flow. Fog and drizzle will remain over the next several hours. May need to watch for radiational fog development tonight across the low lying areas as lingering low level moisture combined with cooling temperatures will create a low temp/dewpoint spread. Dense fog is not expected at this time. Previous Discussion... An area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Isolated lighter showers east of the Worcester Hills tonight. Mainly MVFR all terminals except Coastal MA which will see periods of IFR. VFR across the CT valley. Cigs and vsby improve from west to east after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...Nocera/Dunten SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Nocera/Dunten MARINE...Nocera/Dunten FIRE WEATHER...
Area Forecast Discussion National Weather Service Taunton MA 411 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers and isolated embedded thunderstorms over Western portions of MA and CT will continue into early this evening. Scattered showers may also develop across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 400 PM Update ... Vertically stacked low over the region with -19c air at 500 mb. This cold air aloft combined with cyclonic flow is resulting in scattered showers and embedded thunder. The convection is focused on the western side of the low where SPC mesoanalysis indicates some baroclinicity at 850 mb and 925 mb along with some breaks of sunshine yielding 250-500 j/kg of SB cape per mesoanalysis. This will continue to be the theme thru sunset with convection focused across this region. A second area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Highlights... * Very warm Wed/Thu/Fri with highs well up into the 80s except cooler immediate coast at times * Hot Saturday afternoon w/highs mainly upper 80s to the lower 90s * A few showers/t-storms possible Thu night/Fri but best chance Sat afternoon/evening ahead of cold front * Turning much cooler Sun and especially Mon along the coast Details... Wednesday night...Other than a low risk for a spot shower/t-storm across the interior during the evening dry weather is expected behind a weak cold front. Low temps will only fall back into the 50s in most locations with 60 to 65 in some of the urban centers. A touch of patchy fog may develop in the typically prone locations toward daybreak. Thursday...Upper level ridging across the Southeast U.S. continues to nose into southern New England. This will result in plenty of sunshine and with warm mid level temps, highs again should reach well into the 80s in most locations. However, gradient will be weaker allowing for sea breezes to develop on the immediate Eastern MA coast including Boston by early afternoon. High temps will still likely reach well up into the 70s to near 80 in this region before sea breezes develop and temps fall a bit. Should remain dry given lack of forcing and upper level ridging nosing into this region. Thursday night and Friday...A shortwave will lift northeast into northern New England Thu night/Fri. While the best forcing will to our north, a few showers/t-storms are possible with the best chance across western and northern MA. Certainly not expecting a washout though and the majority of the Thu night/Fri will be dry. Still looks like a warm afternoon with temps into the 80s, but it may be cooler across Northeast MA depending on location of backdoor cold front. Saturday...A hot day with westerly flow and 850T near 16c. This should yield highs in the upper 80s to lower 90s for most locations. Dewpoints into the 60s will make it feel somewhat muggy. Pre-frontal trough ahead of an approaching cold front may trigger scattered showers/thunderstorms mainly Saturday afternoon and evening. Sunday and Monday...High pressure over the Canadian Maritimes will build south into New England. So despite rather high height fields, northeast low level flow will result in much cooler temps Sun and especially Mon particularly along the coast. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Some improvement in vsbys observed over past 1 to 2 hours but cigs slow to rise in onshore flow across much of the area. Believe will begin to rise into the VFR range across the CT River Valley by mid afternoon. Rest of the area should see very slow improvement into at least low MVFR cig range, although there could be a few holdouts below one thousand feet in SE coastal areas. Scattered showers and even isolated thunderstorm or two could develop late this afternoon/evening over portions of RI and SE MA. There could also be scattered showers/isolated thunderstorms that develop during the late afternoon near the Berkshire Crest. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Showers with isolated thunder focused across Western portions of MA and CT. Isolated lighter showers elsewhere. Mainly MVFR all terminals except Coastal MA. Showers dissipate with sunset and cigs and vsby improve after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Showers should stay west of BDL airspace but will be close and need to watch early this evening. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR conditions other than a few hours of patchy ground fog possible toward daybreak Thu in the typically prone locations. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period with the exception being Wednesday night. Some brief near shore southwest wind gusts of 20 to 25 knots are likely Wed afternoon...which will result in some choppy seas. In addition, long southwest fetch may bring a period of 5 foot seas across our southern waters Wednesday night which may require headlines. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera NEAR TERM...Nocera SHORT TERM...Nocera LONG TERM...Frank AVIATION...Frank/Nocera MARINE...Frank/Nocera FIRE WEATHER...Nocera
Area Forecast Discussion National Weather Service New York NY 248 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. This lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... Higher vorticity advection associated with residual cold pool aloft with lingering upper level low combined with increased daytime heating has led to scattered showers and thunderstorms. Some gusty winds and small hail as well as heavy rain are possible for brief periods of time with these thunderstorms. Most of the convection has been confined to Southwest Connecticut and Western Long Island Sound. With CAPE values forecast of a few hundred J/KG more showers and thunderstorms will be possible with coverage being scattered. This will decrease with loss of diurnal heating and as cold pool aloft shift farther east this evening. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... For tonight, the region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest into early this evening. Locally higher amounts will be possible in thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/JP NEAR TERM...JM SHORT TERM...JM LONG TERM...JP AVIATION...MPS MARINE...JM/JP HYDROLOGY...JM/JP
Area Forecast Discussion National Weather Service New York NY 150 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast today and tonight, moving along the New England coast. High pressure builds in briefly for late tonight and Wednesday. A cold front moves through late Wednesday night into Thursday morning and lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... The forecast is pretty much on track here. There were some slight adjustments to better match observed trends with regards to temperatures, dewpoints, and pops for showers. Otherwise though, no remarkable changes were made to the forecast database. A weakening low south of Cape Cod tracks slowly northeast through today. A weak surface trough extends back from the low into the lower Hudson Valley. Meanwhile an upper closed, and nearly cutoff low, east southeast of the Delmarva, as seen on the water vapor loop, drifts north to northeast and begins to fill and get picked up by the northern stream. With areas of energy rotating around the low and the surface low, showers will continue through this morning, eventually becoming more scattered this afternoon. Instability is very weak this morning and generally less than 50 J/KG but this will increase this afternoon to a few hundred J/KG with increased daytime heating at the surface. Forecast includes isolated thunderstorms this afternoon. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Tonight the upper low continues to fill and becomes an open wave after 06Z and the northern stream carries the low into Maine and Nova Scotia, merging with low pressure over eastern Canada. The surface low becomes nearly indistinguishable by late tonight, also merging with a surface low over eastern Canada. By 00Z precipitation is quickly ending as heights rise from as weak upper ridging builds to the west. This ridge builds through Wednesday with dry weather late this evening through Wednesday. Warmer air continues to move into the region tonight through Wednesday at the lower and mid levels. A dramatic warmup is expected across the entire region as a westerly flow allows even coastal areas to warm to well above seasonal normals. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http://www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday as a weakening low south of Cape Cod tracks to the northeast through tonight and high pressure builds in late tonight and Wednesday. The only hazard across the forecast waters will be isolated thunderstorms this afternoon into early this evening. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest of today into this evening. Locally higher amounts will be possible in isolated thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP/MET NEAR TERM...JM/MET SHORT TERM...MET LONG TERM...JP AVIATION...MPS MARINE...JM/JP/MET HYDROLOGY...JP/MET
Area Forecast Discussion National Weather Service Albany NY 147 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure over southeast Long Island will bring scattered to numerous showers across our region from the Capital District south and east today with perhaps a rumble of afternoon thunder. Clouds will keep temperatures a little less warm than yesterday. This storm will move to our east tonight and high pressure will briefly build in through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 134 PM EDT...A closed off upper level low is located just southeast of the region off the coast of southern New England to the east of Long Island. Moisture wrapping around this feature continues to allow for some showers. The bulk of these have been occurring over southern Vermont and into adjacent Washington and Rensselaer Counties New York. Some parts of southern Vermont have seen locally around an inch of rainfall according to the latest MRMS precip estimation. Temps continue to vary from northwest to southeast across the area this afternoon. Thanks to partly to mostly sunny skies, some parts of the central/western Adirondacks have already reached into the mid 70s, while southern and eastern areas seeing lots of clouds remain only in the low 60s. Temps look to be fairly steady for the afternoon hours, with the warmest readings in northwest parts of the area. Most places from Albany on south/east won`t see much sun for the remainder of the day. The latest 16z 3km HRRR suggests that the threat for showers will remain in the forecast for this afternoon, mainly for areas east of the Hudson River. There might be enough instability with colder temperatures aloft for an isolated thunderstorm this afternoon, although most areas won`t see any thunder. Will continue with just a slight chance of thunder for much of the area. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... The cutoff low is forecast to drift east of Cape Cod tonight taking all the showers with it. Weak high pressure will build tonight into early Wednesday with a return to sunshine and higher temperatures back to 80-85 in the valleys, mid to upper 70s over the higher elevations. By afternoon, a weak back door front looks to slip southward into the Adirondacks touching off some scattered showers and possibly thunderstorms. One or two cells could make it south into the Capital region and even northern Catskills. A west to southwest wind 5-15 mph will become northwesterly during the afternoon. The front looks to washout by Wednesday night over the region as it slides to our south. Wednesday night looks dry with perhaps a little patchy fog as the wind will become light or calm overnight. Thursday will start out dry, but with increasing moisture, and perhaps a weak short wave, some scattered showers or thunderstorms could develop by afternoon across the region. These will be hit and miss with many areas likely not getting any rain at all. Otherwise, temperatures will climb in the mid or upper 80s in the valleys, 75-80 higher terrain. Dewpoints will reach the lower 60s in the Hudson valley south of Albany, mid or upper 50s further north so it will feel a little uncomfortably warm to some. && .LONG TERM /FRIDAY THROUGH MONDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. Friday-Friday night...the warm front finally moves through eastern NY and western New England during this time frame. A warm and humid air mass settles in...as dewpoints rise into the 60s. The boundary will likely be in the vicinity of the forecast area...and a weak short-wave in the west to southwest flow aloft will likely focus isolated to scattered showers and thunderstorms. The latest GFS20 has modest SBCAPEs in the 1000-2000 J/kg range, but the amount of deep shear remains uncertain. It is hard to ascertain if the convection will be severe this far out. H850 temps rise to +14C to +16C with highs in the lower to mid 80s in the valley locations...and mid 70s to around 80F over the mountains. The showers and thunderstorms should diminish quickly with the boundary retreating northward and the daytime heating gone. Lows will be upper 50s to lower 60s over most of the forecast area. Saturday-Saturday Night...The subtropical high builds in from the western Atlantic. The ALY forecast get into a warm sector. H850 temps nudge up to +15C to +17C on the latest ECMWF. PWATs increase to 1-1.5 inches. The GFS model soundings do not look very capped. Pop-up diurnally-driven showers and thunderstorms will be possible capable of heavy rainfall. The big question is the timing of the backdoor cold front from Northern New England and southeast Canada. The guidance varies on the timing and placement of the boundary. Our forecast reflects a timing more Saturday night into Sunday. Highs will be steamy for late May with humidity levels on the increase. Highs will be mainly in the mid and upper 80s for elevations at 1000 ft or lower...and upper 70s to lower 80s over the mountains. A slight to low chc of showers and thunderstorms will likely linger most of the night as the backdoor cold front dips south/southwest across the region. Sunday into Memorial Day...Temps look a bit cooler...closer to normal for late May on Sunday...as the backdoor cold front stalls over central NY...eastern PA and northern NJ. The ECMWF has H850 temps fall back to +10C to +12C from east to west over the forecast area...as the cold front moves through...and high pressure builds in from New Brunswick and Nova Scotia. There will continue to be solid chances of showers and thunderstorms as the cold front looks to move through. The amount of instability available will be the main issue for any strong to severe thunderstorms as the shear increases. This will continue to be monitored over the next several days. Highs on Sunday fall back into the mid 70s to lower 80s. Lows Sunday night fall back into the 50s to lower 60s. Memorial Day will feature a threat of a shower or thunderstorm...but it is uncertain where the frontal boundary goes. The latest WPC guidance has it move north into southern Quebec and Northern New England again. When a boundary is in the area with light to moderate amounts of instability and appreciable moisture...then a slight to low chc of showers and thunderstorms...especially in the afternoon will persist through the holiday weekend. Overall...it does not look like a washout at this point. After lows Sunday night in the 50s...highs will likely be in the 70s. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Still some spokes of precipitation rotating around the low pressure system to our east. Have VCSH at all terminals for the afternoon. Not out of the question that a terminal could drop to MVFR conditions in a shower...or perhaps IFR...but chances are slight. Slight chances for TSRA this afternoon as well...but not sufficient to warrant mention in TAFs. So will maintain VFR at all terminals this afternoon. Question for tonight will be how much BR/FG form. All terminals will clear out tonight. Winds will be light. Best chances for FG are at KPSF where showers deposited around 0.2 inch of rain today. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday through 18z. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA...TSRA. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: Moderate Operational Impact. Chance of SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... RH levels should remain elevated today dropping not low than about 50 percent most places. There will be scattered to numerous showers mainly from the Capital region south and eastward. Most areas will likely not receive a quarter inch, except perhaps Litchfield county into the Mid Hudson valley and southern Catskills. The showers will move out tonight leaving us with a nearly fully recovery and likely the formation of dew as the wind will be light. Wednesday, will start out dry and sunny. A weak disturbance could trigger scattered showers and thunderstorms mainly north of the Capital region but a few could stray further south. A full recovery tonight as the showers move out followed by warm increasingly humid weather for the balance of the week. Low pressure tracking close to southern New England will scattered to numerous showers from the Capital region and perhaps an afternoon thunderstorm to locations from the Capital Region south and east. Weak high pressure will build east off the mid Atlantic states and summer like weather will spread across our region from the southwest through the end of next week. The surface wind will be light out of the north or northeast through Tuesday, generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms today. At this time amounts up to a tenth of an inch in our northwestern zones, to quarter to half an inch in our southeastern zones is anticipated. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...HWJIV NEAR TERM...Frugis/HWJIV/OKeefe SHORT TERM...HWJIV LONG TERM...Wasula AVIATION...OKeefe FIRE WEATHER...HWJIV HYDROLOGY...HWJIV/NAS Area Forecast Discussion National Weather Service New York NY 204 PM EDT WED MAY 25 2016 .SYNOPSIS... High pressure builds to the south and east through tonight followed by a weak cold front crossing the area on Thursday. This front then lifts north as a warm front Thursday night, with high pressure building in behind the front through Saturday night. A series of frontal boundaries then impact the area from Sunday into Tuesday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... With high pressure translating off the southeast coast, a sw flow is setting up across the region. The pressure gradient is weak enough and enough land sea temperature differential has led to sea breeze circulations keeping coastal locations relatively cooler than places farther inland. Temperatures are well into the 80s across the region and will reach near 90 for some locations. Sky conditions are sunny without much of any clouds with ridging and thereby subsidence aloft. Temperatures and dewpoints were slightly adjusted to better match observed trends with otherwise no other remarkable changes made to the forecast database. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Deep layered ridging remains in control tonight and Thursday. It will be dry tonight, with only some high clouds around. However, a 700-500 hPa shortwaves passes over the top of the ridge, and through the area Thursday afternoon. This, coupled with surface based CAPE of 500-1000 J/kg, Showalter Indices from -2 to 2, and 20-25kt of Bulk shear over roughly the NW 2/5 of the CWA, warrants slight chance to chance pops in that region. It should be noted that the ECMWF suggests that there should be sufficient subsidence under the ridge to keep things dry throughout the area on Thursday. The GFS however suggests fairly extensive convection over roughly the NW 2/5 of the CWA, with the NAM somewhat in between (though closer to the ECMWF than the GFS). Noting, that in addition to the passing shortwave, will also have a cold front sinking south into the region. Based on this, it appears there is enough forcing to warrant pops at this time. However, there is still the potential for no precipitation at all on Thursday. For lows tonight, a blend of MAV/MET/ECS guidance and NAM 2-meter temperatures was used, with values around 10-15 degrees above normal. A blend of MAV/ECS/MET guidance, NAM 2-meter temperatures and a mix down from 850-750 hPa, per BUFKIT soundings, was used for highs on Thursday. Highs should be around 15 degrees above normal, but probably a degree or so lower than today. If the more extensive convection suggested by the GFS plays out, highs, especially over western areas, might need to be lowered by at least 5 degrees. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Frontal boundary lifts north of the area as a warm front Thursday night. A southerly flow and ridging aloft will allow for the above normal temperatures to continue Friday and Saturday. It will also mean a noticeable increase in humidity as inland areas will see dewpoints into the lower to middle 60s by Friday afternoon, mainly away from the coast. The relatively cool ocean waters will keep temperatures and dewpoints down along coastal areas. However, temperatures across central Nassau and Suffolk may reach the upper 70s to near 80 on both Friday and Saturday. The warm front then approaches our area again late Saturday night into Sunday morning as a back door cold front. High pressure behind this cold front over southeastern Canada slips off the New England coast and into the western Atlantic during this time period. This high is weaker than in previous model runs, and thus will not push as far into our area as previously forecast. This will help to keep the frontal boundary in the vicinity through Monday morning. Sunday`s temperature may be a difficult one depending on which side of the front we will be on. We will be warm sectored on Monday. However, clouds and will keep temperatures down. A cold front then approaches for Tuesday. Something to watch is the disturbance well off the Southeast coast. Models show this disturbance moving inland over the Southeast coast and having little, if any, impact for our area through the forecast period. However, moisture from this system could make its way into our area on Tuesday, but right now it looks like a low chance of that happening. It is still a few days out with a good deal of uncertainty in the forecast. As far as rainfall, nothing looks organized for the long term. There is a fair amount of moisture available given the humid airmass and surface based CAPE values are high for the afternoons from Friday through Monday, but lift does not look overly impressive. Afternoon showers and thunderstorms are possible for areas north and west of NYC Friday and Saturday. Then there is at least a slight chance for the entire area on Sunday with the approach of the back door cold front, which will remain in the vicinity through Monday. Continued unsettled for Tuesday with the approach of the cold front from the west. None of these days are expected to be a washout, just passing showers and thunderstorms. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... High pressure builds in from the west today. VFR forecast. West winds 8-12 kt will back to the SW through this afternoon. Gusts 17-19 kt through this afternoon. SW winds 5-10 kt this evening at KNYC terminals and LGT/VRB elsewhere. Afternoon sea breezes expected on Thursday. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http://www.weather.gov/zny/n90 KJFK TAF Comments: Occasional gusts 18-22 kt this afternoon. Sea breeze also could back winds to the South through this evening. KLGA TAF Comments: Gusts might be only occasional. Winds might back closer to 250-230 magnetic this afternoon. KEWR TAF Comments: Gusts might be only occasional. KTEB TAF Comments: Gusts might be only occasional. KHPN TAF Comments: Gusts might be only occasional. KISP TAF Comments: Gusts might be only occasional. Winds might back closer to 230-210 magnetic this afternoon. .OUTLOOK FOR 18Z Thursday through Monday... .Thursday afternoon...VFR. Afternoon sea breezes. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday through Friday night...Mainly VFR, but sub-VFR possible in isolated showers and evening thunderstorms. .Saturday...Mainly VFR. Isolated showers and thunderstorms north of NYC/Long Island. .Sunday...Sub-VFR possible in afternoon showers and thunderstorms. .Monday...Sub-VFR possible in showers and thunderstorms. && .MARINE... No hazards are expected today with sub SCA conditions as high pressure builds south of the waters. Outside of afternoon seabreezes bring gusts to around 20 kt to the New York Bight Region this afternoon and Thursday, a light to moderate pressure gradient over the area will keep winds to 15 kt or less through Sunday. With no significant swell forecast, these relatively light winds will keep seas below Small Craft Advisory criteria as well throughout the forecast period. && .HYDROLOGY... Dry through Thursday morning. Scattered to Isolated Showers and Thunderstorms, mainly from NYC on N/W Thursday afternoon/evening could bring less than 1/2 inch of rain to that area. There are no significant hydrologic impacts expected from Thursday Night into early next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...Maloit/JP NEAR TERM...JM SHORT TERM...Maloit LONG TERM...JP AVIATION...MPS MARINE...JM/Maloit/JP HYDROLOGY...Maloit/JP
  [top] Area Forecast Discussion National Weather Service Albany NY 200 PM EDT WED MAY 25 2016 .SYNOPSIS... A weak front will move southward from the Saint Lawrence Valley this afternoon. This boundary will eventually stall across the region tonight then move back north as a warm front late in the week. A large Bermuda high will take hold of our weather as we head into the holiday weekend with isolated to scattered showers and thunderstorms each afternoon. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 159 PM EDT...High pressure is ridging in from the south...as a cold front has become stationary near the St Lawrence River Valley. Temps are exceeding current forecasted values...so have increased 2 to 3 degrees with mid and upper 80s possible in the Hudson River Valley. A few showers are possible for the western Adirondacks with a weak disturbance ahead of the front. Slight chc pops were kept in there. Better Chances for any convection should be limited to northern New York and the Adirondacks in the vicinity of the boundary. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... Any convection will dissipate quickly after sunset. We will be left with a clear to partly cloudy night with a summery feel, as low temperatures only dip to around 50 in the coolest spots, 55-60 in most areas, warmest right in the Capital region. The wind will become light and once again there could be a few patches of fog around daybreak. We continue to see some mixed signals in guidance as to coverage of clouds and how extensive any shower or thunderstorm activity will be on Thursday and Friday. It looks as if a weak boundary and another disturbance could trigger some convection later Thursday as dewpoints increase into the 60s, although SBCAPES do not look that high (500-1000 J/KG). Most of the day will be dry and there will a good of deal sunshine as well. Very warm temperatures will likely be a point or two higher than Wednesday. Scattered convection could linger into Thursday night as the aforementioned boundary slowly lifts northward as warm front through our region. By Friday, 500 MB heights continue to rise as an impressive ridge builds just to our south, reaching close to 590 hectopascals , not too shabby for May. Rising heights tend to induce subsidence and capping. Still most models do indicate a scattered of showers and thunderstorms for mainly Friday afternoon so will continue with low chances of thunderstorms. It will be another very warm to hot day with highs 85-90 in the valleys, 80-85 higher terrain. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... Unsettled weather and very warm temperatures are expected during the long term period. There will be chances for showers and thunderstorms each day through Monday with a chance of showers on Tuesday. The activity will be most widespread during the afternoon and evening hours. The forecast area will be impacted by ridge rollers as moisture rides along the top of the ridge which will be anchored to our south. Sunday and Monday are the days during which the thunderstorm activity looks most widespread as a back door cold front drops southwest on Sunday and returns north as a warm front on Monday. Highs on Saturday are expected to be in the upper 70s to upper 80s with highs on Sunday in the mid 70s to mid 80s. Highs on Monday are expected to be in the 70s with mid 70s to lower 80s on Tuesday. Lows Friday night and Saturday night are expected to be in the 60s with lows Sunday night and Monday night in the mid 50s to around 60. Overall temperatures are expected to be well above normal with precipitation above normal. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Aloft, heights will continue to rise as ridging builds in through the overnight into Thursday. At the surface, a cold front is approaching from the Saint Lawrence Valley. This boundary will move gradually southeastward across the region through Thursday. Chances for any convection through the TAF period 18z/Thu should be limited to the northern New York in the vicinity of the boundary this afternoon, north of KGFL. Mainly VFR conditions through the TAF period, 18Z/Thu. The exception will be the possibility will be for MVFR due to fog at KGFL late tonight. Westerly winds with gusts up to 20 knots this afternoon will diminish this evening. Outlook... Thursday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Friday night through Sunday: Moderate Operational Impact. Chance of SHRA...and mainly PM TSRA. Sunday Night: Low Operational Impact. Chance of SHRA. Memorial Day: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... Outside of a few isolated showers or thunderstorms across the Adirondacks, it should be a dry warm day today. RH values will drop into the 30s in most valley locations this afternoon, but stay in the 40s across most of the higher terrain. A west wind will average 10 mph later in the morning through early evening. There will be some gusts to 20 mph across the higher elevations, Mohawk valley and Greater Capital District. A Bermuda high will take control of our weather for the next several upcoming day. This feature will bring very warm increasingly humid days and nights will full recovery. There will be chances of mainly afternoon and evening thunderstorms, especially over the weekend. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Saturday. Today looks mainly dry outside a few possible showers and thunderstorms across the Adirondacks. As a Bermuda high forms, we can expect warm and increasingly humid weather Thursday through the weekend. While most of that time will be rainfree, there is an increasing chance of afternoon and evening thunderstorms each day. These look scattered but as PWATS increase well over an inch, isolated heavy rainfall will possible by Friday afternoon. 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...IAA/Wasula NEAR TERM...IAA/Wasula SHORT TERM...HWJIV/NAS LONG TERM...11 AVIATION...IAA/HWJIV FIRE WEATHER...HWJIV HYDROLOGY...HWJIV/NAS
  [top] Area Forecast Discussion National Weather Service Taunton MA 1026 AM EDT WED MAY 25 2016 .SYNOPSIS... An upper level ridge will bring very warm weather to most of the region through Saturday, except for cooler temperatures at times along the immediate coast. A backdoor cold front will bring cooler weather to the region sometime on Sunday, but temperatures should rebound to at or above normal by early next week. A few showers and thunderstorms are possible Thursday night into Friday, and again this weekend but the vast majority of this time will be dry. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... ***Summer temperatures push in today across the region*** 1030 AM Update...Most of the fog has cleared out across the area with the exception of one band of fog that is hugging the south coast of RI and moving eastward towards Buzzards Bay and the Cape. If it continues on this trajectory without burning off, portions of Cape Cod along the Cape Cod Canal as well as Martha`s Vineyard and the Elizabeth Islands will see a period of fog later this morning into early afternoon. Visibilities have been generally about a mile with this bank of fog on land, it may be more dense over the water. Made minor adjustments to the temperatures to ease them back as they have not jumped up as quickly as forecast. Otherwise, the previous forecast is on track. Weak ridging at the surface and aloft will cross the region by midday through the afternoon with NW winds aloft. Warm core H925 temps will push across the region, up to +19C to +22C by this afternoon. Once skies become mostly sunny, temps will rise quickly with excellent low and mid level mixing in place. Expect temps to top off in the mid-upper 80s with a few spots touching 90. However, dewpoints falling into the 40s will result in low humidity levels. High clouds will start to push in from the NW during the mid and late afternoon ahead of H5 short wave across far northern New England. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Tonight... Most of the energy from a weak H5 shortwave trough will remain across northern New England. NW flow keeps dry conditions across the region tonight. The mid and upper level clouds will dissipate overnight as SW winds shift back to W-NW and diminish. It will remain mild, with temperatures only bottoming out from the mid 50s well inland to lower-mid 60s across the coastal plain. Thursday... A cold front will slowly push S across the region during the day. Clouds will push in from the W as the front moves in during the afternoon. Short range models vary in their solutions, with mainly dry conditions through the day offered by the ECMWF, but the GFS tends to bring some moisture with a weak H5 shortwave in the W-NW flow aloft. Have mentioned only slight chance PoPs moving into W MA/N Central CT during the mid and late afternoon hours. Have noted marginal instability with this system, plus another day of warm temperatures, so have mentioned widely scattered showers/isolated thunderstorms. It will be another warm day, with somewhat higher dewpoints making it feel a bit more humid. Highs will again be in the mid-upper 80s away from the immediate coast, with a few spots possibly hitting 90 again. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Highlights... * Friday: Very warm w/highs mid-upper 80s northwest of BOS-PVD but a bit cooler across southeast MA/RI * Saturday: Hot and a bit humid w/highs mainly upper 80s to lower 90s away from the immediate south coast * Sunday: Temps uncertain depending on timing of cold front, warmest readings likely CT River Valley w/coolest across Eastern MA coast * A few showers/t-storms possible Thu night/Fri and again Sat/Sun but the vast majority of this time will be dry * At or above normal temperatures likely return early next week Details... Thursday night...Shortwave energy and a burst of elevated instability may result in a few showers/t-storms Thursday night, mainly northwest of a Boston to Providence line. If any activity is able to develop, it will be short-lived with the majority of the night ending up dry. Low temps mainly in the upper 50s to the lower 60s. May see some patchy ground fog develop late in the typically prone locations. Friday...Surface winds shift to the south-southwest behind the warm front as 850T rise to around +14C. Plenty of sunshine should allow highs to warm into the middle to upper 80s northwest of a Boston to Providence line. Southeast of this line...a cooling marine layer may hold highs in the upper 70s to the lower 80s. Dry weather will dominate on Friday, but enough instability combined with a pre-frontal trough may allow a few showers/thunderstorms to develop across W MA/N CT Fri afternoon and evening. Not sure if this activity gets into our region or stays to our west, but highest risk will be across northwest MA. Shear is rather weak so even if we see a few thunderstorms in our western zones, overall severe weather threat is rather low. Saturday...A hot and somewhat humid day is on tap to kick off the Memorial Day Weekend. 850T around +16C, plenty of sunshine, and a westerly component to the surface winds should allow for high temps to reach into the upper 80s to the lower 90s away from the immediate south coast. Dewpoints between 60 and 65 across most of the region will make it feel a bit humid. While most of the day will be dry, a few showers and thunderstorms may develop Saturday afternoon and evening with a pre-frontal trough and CAPE values between 1000 and 2000 J/KG. This will be mainly to the northwest of a Boston to Providence line. Forcing will be rather weak, so areal coverage of any activity that develops may remain limited. Severe weather threat also looks rather low at this time with rather weak 0 to 6 km shear, but too early to rule out a strong thunderstorm or two given decent instability. Sunday...Low confidence on high temperatures given a subtle change in timing of the backdoor cold front will make a big difference in the exact outcome. We can say that the warmest readings will be across the lower CT River Valley and coolest along the eastern MA coast. Good shot though at the CT River Valley seeing high temps reaching well into the 80s, while the eastern MA coast has afternoon temps falling into the 60s. A few showers will remain possible and perhaps even a couple of t-storms across the interior if enough instability develops during the afternoon. Monday and Tuesday...Backdoor cold front does not appear as strong on the latest model runs. It looks to washout across the region early next week. GFS washes out on Monday while the ECMWF waits until Tuesday. Probably should see the return to above normal temps by Tue with rather warm temps aloft. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Today...High confidence. VFR conditions expected the rest of the day, except on the Cape and Islands where fog may reduce visibilities down to MVFR/IFR at times. Tonight...High confidence. VFR conditions. W-NW winds 10 kt or less. Thursday...High confidence. VFR. Light W-NW winds, except sea breezes possible late morning/afternoon along the coast. KBOS TAF...Moderate to high confidence. An ESE sea breeze has developed and is expected to continue into early afternoon. Southwesterly winds should overcome this by late afternoon. KBDL TAF...High confidence in TAF. Outlook /Thursday Night through Sunday/... Thursday night and Friday...Moderate to high confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few brief showers/t-storms mainly across the interior. Also, some patchy ground fog possible in the typically prone locations very early Fri AM. Saturday...Moderate to high confidence. VFR conditions likely dominate but a brief period of MVFR-IFR cigs/vsbys possible in a few afternoon and evening showers/thunderstorms. Sunday...Low confidence. MVFR-IFR conditions may develop from east to west behind a backdoor cold front. A few thunderstorms also possible Sun afternoon across the interior. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Today...High confidence. W winds up to 10 kt will back to SW 10-15 kt this afternoon with gusts up to 20 kt on the southern outer waters. Seas 4 ft or less. Patchy fog mainly along the south coast will result in reduced visibilities at times. Tonight...High confidence. Light southwesterly winds become westerly, gusting up to 20 kt on the southern outer waters this evening. Seas 4 ft or less. Thursday...High confidence. Light W winds shifting to S in the afternoon. Seas remain below 5 ft. Outlook /Thursday Night through Sunday/...High Confidence. Winds and seas will generally remain below Small Craft Advisory thresholds through the period. The main concerns are a period of near-shore southwesterly wind gusts of 20 to 25 knots Saturday afternoon which will result in some choppy seas for mariners. May also see some brief easterly wind gusts between 20 and 25 knots on Sunday behind a backdoor cold front. && .FIRE WEATHER... Today...Expect temperatures will rise quickly, soaring well into the 80s to near 90 across most locations except cooler along the immediate south coast. These temperatures will combine with dewpoints dropping into the 40s resulting in afternoon RH values down to between 20 and 30 percent. A few hours of westerly wind gusts up to 20 to perhaps briefly 25 mph are anticipated. Given Tuesday`s rainfall and marginal criteria, will fall short of needing fire weather headlines. Many locations are close to or already at full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert until 11 PM EDT this evening for MAZ020>024. RI...Air Quality Alert until 11 PM EDT this evening for RIZ003-004- 006>008. MARINE...None. && $$ SYNOPSIS...Frank/EVT NEAR TERM...Frank/RLG/EVT SHORT TERM...EVT LONG TERM...Frank AVIATION...Frank/EVT MARINE...Frank/EVT FIRE WEATHER...Staff
Area Forecast Discussion National Weather Service Taunton MA 229 AM EDT WED MAY 25 2016 .SYNOPSIS... A few leftover showers may fall across western MA and north central Conn., as well as south coastal MA and RI through the early this morning as low pressure slowly moves northeast to the Gulf of Maine. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 145 AM Update... H5 cutoff low has pushed just E of Cape Cod as seen on latest water vapor and IR satellite imagery. Winds have diminished to near calm away from the coast at 05Z obs. Noting patchy dense fog has started to form across portions of the CT valley into NE CT. May see more develop over the next few hours across central and western areas. May also see a few showers develop with the last of the band crossing out the Berkshires through 08Z-09Z. Remainder of previous forecast in pretty good shape, but have updated to bring current. Previous discussion... With light winds across the region, along with lowering temp/dewpoint spreads, will still see patchy fog develop along with lingering low clouds from around Worcester and Windham counties eastward through around midnight, but trends continue to indicate that this should slowly push E during the early morning hours as the low exits, but will be slowest across E coastal MA. Partial clearing should begin moving into the CT valley after midnight as winds back to light NW, then will slowly shift E overnight. Clouds will linger along the E coast through daybreak. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/... *** Summer-like Temperatures Move in Today *** Today ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through 12Z...Moderate confidence, though lower in timing of improving conditions toward daybreak. Areas of IFR-LIFR CIGS and mixture of VFR to IFR VSBYS in patchy fog, lowest across interior E MA and portions of CT valley into NE CT. Should start to see conditions improve to VFR across CT valley after 08Z, then slowly progressing E after daybreak. Calm or light/vrbl winds. Today...Moderate confidence this morning, then high confidence. IFR CIGS and areas of MVFR-IFR VSBYS across central-E MA/RI should improve by mid morning. Otherwise, VFR. W-SW winds 10 kt or less. Tonight...High confidence. VFR conditions. W-NW winds less than 10 kt. Thursday...High confidence. VFR. Light W-NW winds, except sea breezes possible late morning/afternoon along the coast. KBOS TAF...Moderate confidence. Uncertain on exact timing of improvement, but should take place by around 10Z. KBDL TAF...Moderate confidence. otherwise VFR. Outlook /Thursday Night through Sunday/... Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through 12Z...High confidence. Upper level low will slowly move into Massachusetts Bay during the early morning hours. Light E-NE winds across the eastern waters will back to N-NW, becoming mainly W of all waters toward daybreak. Leftover SE swells will linger on the outer waters E and S of Cape Cod, but should subside below 5 ft by around 08Z- 09Z. Visibility restrictions in patchy fog, locally dense in some locations, should improve from W-E. Today...High confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Tonight...High confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday Night through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... Wednesday...High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given today`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for MAZ020>024. RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for RIZ003-004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT early this morning for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...EVT SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Dunten/EVT MARINE...Nocera/Dunten/EVT FIRE WEATHER...Staff
Area Forecast Discussion National Weather Service Albany NY 210 AM EDT WED MAY 25 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... As of 210 AM EDT...showers have dissipated across all of our region, and so have many of the clouds. However, as moisture pooled from the Hudson valley eastward, patchy dense fog was beginning to form from the Hudson valley eastward with dewpoints still around 50 or higher, compared to much lower levels just west, where they were from the upper 30s to mid 40s. At this time of night, with decoupling, there really is no way for these dewpoints to advect further east, so we don`t expect much in them overnight. We did however, lower some places a couple of degrees. Look for lows generally 45-50 with light or calm wind. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... It looks as if we will dealing with quite a bit of IFR flying conditions through 11Z thanks to residual low level moisture trapped in the Hudson valley and Berkshires. This despite our local Fog study program did not forecast any fog in any of the TAFs. As of 06Z Low IFR was already reported at KGFL and KPSF. While KALB was still VFR their remarks indicated patches of fog (BCFG) so we believe they too will have at least temporary times of IFR. KPOU looks to have some IFR fog although studies have indicated it is hard to fog at the site. Any and all fog will be gone before 12Z leaving us to a VFR flying day as dry air will mix down as a breeze kicks in from the west, 5- 10KTS, gusting to 20KTS by midday at KPSF and KALB. After 12Z clouds will be few-sct with some cumulus around 5 KFT and a few higher clouds at times. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...HWJIV/BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...HWJIV/BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS
Area Forecast Discussion National Weather Service New York NY 959 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure departs to the northeast as high pressure builds to the south on Wednesday. A cold front moves through on Thursday. High pressure will then dominate through Saturday night as a series of weak upper level disturbances move across. A cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. persistent showers continue to track down from new england...so have added chc pops for a few more hours as a weakening trend is noted on radar as well as in the hrrr. dry weather should return by midnight with decreasing clouds overnight. have also added patchy fog to ct coastal areas and ern long island overnight with light winds and high moisture content at the sfc. Otherwise...minor adjustments made to hourly t/td. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. With lighter winds across the interior, min temperatures were further lowered by a degree. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south overnight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light overnight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... light pcpn amounts (less than 1/10 inch) in any remaining showers this eve. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
Area Forecast Discussion National Weather Service Albany NY 812 PM EDT TUE MAY 24 2016 .SYNOPSIS... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... As of 800 PM EDT...Weak deformation axis association with scattered to broken band of showers just east of the Hudson River should continue into the evening hours. The upper low in the vicinity of Providence, RI is beginning to show signs of tracking ENE per the latest H2O loop analysis. With this movement we should see a diminishing trend in the showers which too is suggested by the HRRR. So main update was to the sky coverage, PoPs/WX, removed the mention of thunder and expanded the fog a little further west to include the Hudson River Valley overnight as skies should clear overnight under diminishing winds. Question will be just how much fog impact will occur as dewpoints upstream were between 30-40F compared to mid 50s across eastern NY. We will monitor closely. Prev disc...Upper low departing northeast slowly but steadily. Very narrow band of rain in eastern NY with some isolated thunderstorms from the Berkshires through NW CT and the mid Hudson Valley. Rain and isolated thunderstorms will build east and dissipate through the evening...and clearing will take place through the night. Quite a bit of clearing outside of the moisture field of the upper low...so by daybreak most areas should be clear to mostly clear. There could be some patchy fog as low level winds should trend to calm and areas with wet ground could support some patchy fog but with dryer surface dewpoints advecting in...it could minimize chances for fog. Only including patchy fog for areas east of the Hudson Valley into western New England where most of the rain has fallen. Lows in the mid 40s to lower 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Good consensus in guidance for sunny to mostly sunny sky over most of our region Wednesday...but weak upper energy scraping far northern areas...along with a tightening of the boundary layer temperature gradient could support some isolated to scattered afternoon thunderstorms. Winds from the surface through the boundary layer are expected to be west...and could be a bit gusty in the afternoon. The mixing should help temperatures reach the lower to mid 80s in many areas...a few upper 80s mid Hudson Valley and upper 70s to lower 80s northern areas. Some mixed signals in guidance as to coverage of clouds and isolated to scattered showers and thunderstorms Thursday and Friday. Wherever the weak boundary stalls Wednesday night...will return north Thursday...and could be a diffuse focus for some isolated to scattered afternoon thunderstorms in northern areas. Increasing low level moisture and instability could support diurnal type isolated to scattered afternoon and evening thunderstorms in other areas of terrain Thursday afternoon and evening and again Friday afternoon and evening. There could be some old convective debris that could filter the sun at times Thursday and Friday...too. Upper level ridging and low level ridging build east...allowing for deep southwest flow...warming boundary layer temperatures and increasing low level humidity. Highs Thursday in the mid to upper 80s with around 80 to lower 80s in higher terrain. Highs Friday in the mid to upper 80s...but around 90 southern areas and lower 80s northern areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. A very active weather pattern across the eastern seaboard as we monitor the tropics, frontal boundary nearby along with increasing temperatures and humidity /along with the heat index/. We are well into the warm sector Friday night as H850 temps surge well into the mid-teens which should continue into the weekend. However, several instability factors also climb, although, shear parameters are less than ideal. Through Saturday, ridge axis at the surface and especially aloft builds across the region. As dewpoints climb well into the 60s and PWATS climbing toward 1.50 inches, it will definitely feel more like summer. Surface based CAPES too climb toward 2000 J/KG /even higher with slight modifications of the soundings/ with surface lifted index values to at or below -5c. So plenty of instability around but aforementioned shear parameters are generally 15kts or less. For now, we will leave the chance-scattered PoPs in the grids. Later into the holiday weekend will be the position of the backdoor front as the GFS is the most aggressive with taking this front well west of the region with the ECMWF/GGEM remaining somewhat stationary across eastern NY. If the later scenario were to verify, the potential for not only additional convection but heavy rainfall would be another concern. For now, we will leave in the chance- scattered PoPs along with partly cloudy-mostly cloudy conditions. For Memorial Day, confidence is rather low as we monitor the potential tropical entity along the east coast. Please refer to the latest tropical outlooks issued by the National Hurricane Center. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Showers continue to impact the Hudson River Valley and points east which is mainly where our TAFs are located. Included a VCSH or a TEMPO group for the next few hours. Otherwise, VFR conditions through the evening hours. The question for tonight will be how much BR/FG form. All terminals will clear out overnight. Winds will be light but dewpoints upstream are about 10-15 degrees cooler than those observed across eastern NY and western NE. At this time, the best IFR chances for FG are at KPSF/KGFL where showers and trapped moisture near the inversion. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Isolated SHRA...TSRA. Friday: Moderate Operational Impact. Scattered SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... High pressure will briefly build into our region through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather with isolated to scattered showers and thunderstorms each afternoon into the weekend. RH values at night tonight and tomorrow night should be in the 70 to 100 percent range. Minimum RH values Wednesday afternoon are expected to be 30 to 40 percent in southern areas and 40 to 55 percent in northern areas. Minimum RH values on Thursday afternoon should be 40 to 55 percent. The surface wind will be light and variable tonight...generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. Winds trend to near calm Wednesday night and then become south at 15 mph or less Thursday. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms through this evening. At this time additional rainfall amounts of up to a tenth of an inch in most areas...with some isolated quarter inch amounts in any thunderstorms in the mid Hudson Valley...Berkshires and NW CT. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...NAS NEAR TERM...BGM/NAS SHORT TERM...NAS LONG TERM...BGM AVIATION...BGM/OKeefe FIRE WEATHER...NAS HYDROLOGY...NAS www.weather.gov/albany
Area Forecast Discussion National Weather Service New York NY 737 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. High pressure will dominate through Saturday night as a series of weak upper level disturbances move across. A back door cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... The forecast is generally on track. Made some adjustments to pops next couple of hours based on latest radar trends. Showers continue to weaken this eve and dry weather should return by midnight. Otherwise...minor adjustments made to hourly t/td and winds. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. Also with lighter winds across the interior and residual low level moisture...there could be some patchy fog late into early Wednesday Morning. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /23Z TUESDAY THROUGH SUNDAY/... Low pressure departs to the northeast as high pressure builds to the south tonight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light tonight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: No unscheduled amendments this evening. A late day seabreeze is expected Wednesday. KLGA TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KEWR TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KTEB TAF Comments: No unscheduled amendments this evening. West winds will increase by afternoon with occasional gusts expected. KHPN TAF Comments: Patchy fog is possible overnight. West winds will increase by afternoon with occasional gusts expected. KISP TAF Comments: No unscheduled amendments this evening. A late day seabreeze may approach the airport Wednesday, but do not expect the seabreeze to move through at this time. .OUTLOOK FOR 00Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected into early this evening. Locally higher amounts will be possible in thunderstorms. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$
Area Forecast Discussion National Weather Service Taunton MA 703 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers will continue across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 700 PM Update... Overall forecast is on track. Removed the thunder mention for this evening as convection has remained just west of southern New England. Also increased precip trends across RI and southeast MA as area of showers continues to develop and spin as the upper level low begins to slowly shift eastward. Otherwise breaks of sun across western MA as allowed for temps to warm in to the upper 60s late this afternoon. Onshore flow across eastern MA will continue until the low shifts eastward creating more of a northerly flow. Fog and drizzle will remain over the next several hours. May need to watch for radiational fog development tonight across the low lying areas as lingering low level moisture combined with cooling temperatures will create a low temp/dewpoint spread. Dense fog is not expected at this time. Previous Discussion... An area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HIGHLIGHTS... * Well above average temperatures for Thu and Fri with the potential for a spot thunderstorm * Hazy, Hot and Humid for Saturday with locations reaching 90+F * Scattered showers and thunderstorms are possible on Saturday * Back door cold front on Sunday will keep conditions cool into Monday OVERVIEW... Large scale pattern is in agreement with both determinisic and ensemble guidance. Upper level trough will move eastward towards the Maritimes as Midwest ridge builds into the Northeast. Anomalous high pressure over the western Atlantic will continue to build this ridge through Saturday. Anticipate summer-like warmth and humidity to return to the region as ensembles show both the 700 and 500 heights nearly 1-2 standard deviations above normal. Several waves will move through the flow keeping a chance of showers and thunderstorms in the forecast for Late Thursday and again on Saturday. Because of the mesoscale differences in the guidance trended the forecast towards an overall blend. Back door cold front will swing through by Sunday cooling the area down. However, on Monday, still some discrepancies with offshore high pressure. The GFS keeps it closer to the coast keeping temps on Monday cooler while the EC is weaker and more offshore. Continued with a model blend for now. DAILIES... Thursday into Friday...High Confidence. Upper level ridge will build into the region on each day. Anticipate the warm weather to continue into Thursday as 925 mb temps are generally around 20C. This warm airmass combined with westerly flow and the warm May sun will help aid in high temps reaching into the mid to upper 80s with a few 90s near the CT valley. Conditions look to be cooler along the MA coastline as a sea breeze will develop from weak winds aloft. A spot shower or thunderstorm may develop in the afternoon, but most of the region will remain dry. Weak shortwave will pass through the flow Thursday night. Due to building heights across the region and weak southwesterly flow, appears that the better forcing will be north of southern New England. However, cannot rule out the potential for precip Thursday night into Friday morning across the north and northwest portion of the region. Guidance continues to highlight the potential for elevated convection so continued the mention for thunder in the forecast for now. Temperatures on Friday look to be similar as they will be on Thursday with heights in the mid to upper 80s with a few 90F across the CT valley. Still a large spread in the guidance on if Boston will reach 80F as there is question in the sea breeze development. However 925 mb winds appear to be strong enough to allow for good SW flow to warm the immediate eastern coastline. This southwest flow will keep the south coast cooler thanks to onshore flow and the cooler ocean waters. Once again a spot shower looks to be possible in the afternoon, but better forcing and instability appears to remain west of the region. So another dry weather day is expected. Saturday...Moderate Confidence Upper level ridge will strengthen across the the eastern Great Lakes as warm front lifts northward. A very warm day will be on tap as 925 mb temps will warm to 23-24C. Ensembles continue to show probabilities that many locations could reach above 90F. This hazy, hot and humid day does have some caveats. Approaching surface trough looks to trigger afternoon convection for the region. Some storms could be strong or severe, but a bit to early to tell. Sunday into Monday...Moderate Confidence. Back door cold front will swing through the region late Saturday night into Sunday. This will cool temperatures down across the region. The front does look to push and stall across the Hudson. However, could still see upper 70s or low 80s across the CT river valley as 925 mb temps are between 18-20C. Otherwise anticipate a cooler weather day. Still large spread for surface temps on Monday. GFS and EC have about a 15 degree difference amongst each other. The GFS is cooler with highs in the low 70s while the EC is warmer with highs in the low 80s. Continued with a model blend for now to split the difference. May see a few sct showers on Monday depending on the location of the southeast low pressure system and how quickly it moves northwards towards the region. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Isolated lighter showers east of the Worcester Hills tonight. Mainly MVFR all terminals except Coastal MA which will see periods of IFR. VFR across the CT valley. Cigs and vsby improve from west to east after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. Sunday...Low confidence. MVFR conditions to start with some improvements on Sunday as a back door front swings through. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period. Could see some brief near shore southwest wind gusts of 15 to 20 knots are possible Friday and Saturday...which will result in some choppy seas. Otherwise could see some afternoon convection on Saturday as a back door cold front swings through. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera/Dunten NEAR TERM...Nocera/Dunten SHORT TERM...Nocera LONG TERM...Dunten AVIATION...Nocera/Dunten MARINE...Nocera/Dunten FIRE WEATHER...
Area Forecast Discussion National Weather Service Taunton MA 411 PM EDT TUE MAY 24 2016 .SYNOPSIS... Scattered showers and isolated embedded thunderstorms over Western portions of MA and CT will continue into early this evening. Scattered showers may also develop across portions of Southern RI and southeast MA early this evening as low pressure slowly moves across southeastern New England. An upper level high pressure ridge will then bring very warm to hot weather to most of the region Wednesday through Saturday, except for cooler temperatures at times on the immediate coast. A few showers and thunderstorms are possible Thursday night into Friday, but a better chance exists Saturday afternoon and evening ahead of a backdoor cold front. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 400 PM Update ... Vertically stacked low over the region with -19c air at 500 mb. This cold air aloft combined with cyclonic flow is resulting in scattered showers and embedded thunder. The convection is focused on the western side of the low where SPC mesoanalysis indicates some baroclinicity at 850 mb and 925 mb along with some breaks of sunshine yielding 250-500 j/kg of SB cape per mesoanalysis. This will continue to be the theme thru sunset with convection focused across this region. A second area of showers may develop over Southern-Southeastern RI into Southeast MA as plume of deeper moisture pivots northeast off the ocean into that area. This is supported by multi model K indices and latest trends seen on water vapor satellite imagery. Already seeing the first signs of this with light showers developing over Marthas Vineyard and Elizabeth Islands. However these showers should be weak/low top with not a lot of impact. Thus not a washout expected this evening. Otherwise drying trend second half of the night as vertically stacked low moves offshore by sunrise. Temps seasonably cool tonight with lows in the upper 40s to low 50s. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... *** Summer-like Temperatures Arrive Wednesday *** 4 pm update ... Wednesday ... Vertically stacked low just east of Cape Cod at 12z/8am but ejects seaward quickly with rising heights and northwest flow aloft by midday. Thus any cloudiness across Eastern MA at sunrise quickly erodes and/or moves offshore with abundant sunshine for the afternoon. Warming temps aloft to +14c at 850 mb and +21c at 925 mb yields surface temps at least 30C/86F. Although with boundary layer mixing beyond 850 mb highs will make a run at 90 in many locations. However humidity will be low with dew pts only in the mid to upper 40s. Not as warm along the South Coast including Cape Cod and the Islands...where winds will bend to the southwest off the cooler ocean waters. Wed night ... Dry, tranquil weather with mid level ridge and associated anticyclonic flow continuing to build across the region from the west. Dry airmass in place along with diminishing winds and mostly clear skies will allow temps to fall into the 50s...except 60-65 in the urban areas. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Highlights... * Very warm Wed/Thu/Fri with highs well up into the 80s except cooler immediate coast at times * Hot Saturday afternoon w/highs mainly upper 80s to the lower 90s * A few showers/t-storms possible Thu night/Fri but best chance Sat afternoon/evening ahead of cold front * Turning much cooler Sun and especially Mon along the coast Details... Wednesday night...Other than a low risk for a spot shower/t-storm across the interior during the evening dry weather is expected behind a weak cold front. Low temps will only fall back into the 50s in most locations with 60 to 65 in some of the urban centers. A touch of patchy fog may develop in the typically prone locations toward daybreak. Thursday...Upper level ridging across the Southeast U.S. continues to nose into southern New England. This will result in plenty of sunshine and with warm mid level temps, highs again should reach well into the 80s in most locations. However, gradient will be weaker allowing for sea breezes to develop on the immediate Eastern MA coast including Boston by early afternoon. High temps will still likely reach well up into the 70s to near 80 in this region before sea breezes develop and temps fall a bit. Should remain dry given lack of forcing and upper level ridging nosing into this region. Thursday night and Friday...A shortwave will lift northeast into northern New England Thu night/Fri. While the best forcing will to our north, a few showers/t-storms are possible with the best chance across western and northern MA. Certainly not expecting a washout though and the majority of the Thu night/Fri will be dry. Still looks like a warm afternoon with temps into the 80s, but it may be cooler across Northeast MA depending on location of backdoor cold front. Saturday...A hot day with westerly flow and 850T near 16c. This should yield highs in the upper 80s to lower 90s for most locations. Dewpoints into the 60s will make it feel somewhat muggy. Pre-frontal trough ahead of an approaching cold front may trigger scattered showers/thunderstorms mainly Saturday afternoon and evening. Sunday and Monday...High pressure over the Canadian Maritimes will build south into New England. So despite rather high height fields, northeast low level flow will result in much cooler temps Sun and especially Mon particularly along the coast. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Some improvement in vsbys observed over past 1 to 2 hours but cigs slow to rise in onshore flow across much of the area. Believe will begin to rise into the VFR range across the CT River Valley by mid afternoon. Rest of the area should see very slow improvement into at least low MVFR cig range, although there could be a few holdouts below one thousand feet in SE coastal areas. Scattered showers and even isolated thunderstorm or two could develop late this afternoon/evening over portions of RI and SE MA. There could also be scattered showers/isolated thunderstorms that develop during the late afternoon near the Berkshire Crest. Tonight ... Moderate confidence with uncertainty centered around except timing of improving conditions overnight. Showers with isolated thunder focused across Western portions of MA and CT. Isolated lighter showers elsewhere. Mainly MVFR all terminals except Coastal MA. Showers dissipate with sunset and cigs and vsby improve after 06z. Wed ... high confidence. Any leftover MVFR cigs at sunrise will be across Eastern MA but quickly lifting to VFR by 15z or sooner. Dry weather and west winds except southwest along the coast. Wed night ... high confidence. VFR/DRY and light sw winds becoming west. KBOS TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 06z. KBDL TAF ... Moderate confidence. Some uncertainty on exact timing of improvement but should take place around 03z-06z. Showers should stay west of BDL airspace but will be close and need to watch early this evening. Outlook /Thursday through Sunday/... Thursday...High confidence. VFR conditions other than a few hours of patchy ground fog possible toward daybreak Thu in the typically prone locations. Thursday night and Friday...Moderate confidence. VFR conditions likely dominate but some brief MVFR conditions possible in a few showers/t-storms mainly across the interior. Saturday...Moderate confidence. Mainly VFR conditions but brief MVFR- IFR conditions possible Saturday afternoon/evening in scattered showers and thunderstorms. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 4 pm update ... Tonight ... high confidence except uncertainty on areal coverage of showers and exact timing. Vertically stacked low over the RI waters will slowly drift to Cape Cod by morning. Few light rain showers will accompany this low along with patchy fog. Leftover southeast swell of 3-6 ft continue across the Southeast MA ocean waters. Wed ... high confidence on all weather parameters. Low pressure near Cape Cod at sunrise moves east/offshore by midday with a drying trend and vsby improving to the horizon. Winds become southwest by midday. Wed night ... high confidence. Light southwest winds become westerly. Dry weather and vsby continue. Outlook /Thursday through Sunday/...High Confidence. Winds and seas will remain below Small Craft Advisory thresholds the majority of the period with the exception being Wednesday night. Some brief near shore southwest wind gusts of 20 to 25 knots are likely Wed afternoon...which will result in some choppy seas. In addition, long southwest fetch may bring a period of 5 foot seas across our southern waters Wednesday night which may require headlines. && .FIRE WEATHER... 4 pm update ... Wednesday ... High temperatures soaring well into the 80s to near 90 in most locations will result in minimum afternoon RH values dropping to between 20 and 30 percent. A few hours of westerly wind gusts of 20 to 25 mph are anticipated. Given this morning`s rainfall and marginal criteria, will probably fall short on the need for fire weather headlines especially given many locations are near full green-up. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for MAZ020>024. RI...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for RIZ003- 004-006>008. MARINE...Small Craft Advisory for hazardous seas until 4 AM EDT Wednesday for ANZ254-255. && $$ SYNOPSIS...Nocera NEAR TERM...Nocera SHORT TERM...Nocera LONG TERM...Frank AVIATION...Frank/Nocera MARINE...Frank/Nocera FIRE WEATHER...Nocera
Area Forecast Discussion National Weather Service New York NY 248 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast through tonight, moving into the Gulf of Maine. An associated weak surface trough will move east of the region tonight. High pressure builds in from the southwest briefly for late tonight and Wednesday. This weakens and moves farther offshore Wednesday Night as a weakening cold front moves through by early Thursday. This lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... Higher vorticity advection associated with residual cold pool aloft with lingering upper level low combined with increased daytime heating has led to scattered showers and thunderstorms. Some gusty winds and small hail as well as heavy rain are possible for brief periods of time with these thunderstorms. Most of the convection has been confined to Southwest Connecticut and Western Long Island Sound. With CAPE values forecast of a few hundred J/KG more showers and thunderstorms will be possible with coverage being scattered. This will decrease with loss of diurnal heating and as cold pool aloft shift farther east this evening. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... For tonight, the region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. 850mb temperatures increase through the night. A light westerly flow is conveyed by the models which will help mix down some relatively warmer air tonight despite the decrease in clouds, thereby mitigating radiational cooling. With lighter winds across the interior, min temperatures were further lowered by a degree. For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest into early this evening. Locally higher amounts will be possible in thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/JP NEAR TERM...JM SHORT TERM...JM LONG TERM...JP AVIATION...MPS MARINE...JM/JP HYDROLOGY...JM/JP
Area Forecast Discussion National Weather Service New York NY 150 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure south of Cape Cod tracks northeast today and tonight, moving along the New England coast. High pressure builds in briefly for late tonight and Wednesday. A cold front moves through late Wednesday night into Thursday morning and lifts north as a warm front later in the day Thursday. High pressure remains situated over the western Atlantic through the first half of the weekend. A backdoor cold front moves through on late Saturday night into Sunday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... The forecast is pretty much on track here. There were some slight adjustments to better match observed trends with regards to temperatures, dewpoints, and pops for showers. Otherwise though, no remarkable changes were made to the forecast database. A weakening low south of Cape Cod tracks slowly northeast through today. A weak surface trough extends back from the low into the lower Hudson Valley. Meanwhile an upper closed, and nearly cutoff low, east southeast of the Delmarva, as seen on the water vapor loop, drifts north to northeast and begins to fill and get picked up by the northern stream. With areas of energy rotating around the low and the surface low, showers will continue through this morning, eventually becoming more scattered this afternoon. Instability is very weak this morning and generally less than 50 J/KG but this will increase this afternoon to a few hundred J/KG with increased daytime heating at the surface. Forecast includes isolated thunderstorms this afternoon. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Tonight the upper low continues to fill and becomes an open wave after 06Z and the northern stream carries the low into Maine and Nova Scotia, merging with low pressure over eastern Canada. The surface low becomes nearly indistinguishable by late tonight, also merging with a surface low over eastern Canada. By 00Z precipitation is quickly ending as heights rise from as weak upper ridging builds to the west. This ridge builds through Wednesday with dry weather late this evening through Wednesday. Warmer air continues to move into the region tonight through Wednesday at the lower and mid levels. A dramatic warmup is expected across the entire region as a westerly flow allows even coastal areas to warm to well above seasonal normals. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... A weak area of low pressure over the Canadian Maritimes will push a cold front through the area Wednesday night. This front will then head quickly back north as a warm front, moving through Thursday afternoon. Thereafter, there will be a prolonged period of southerly flow as surface high pressure settles over the Western Atlantic. At the same time, ridging aloft will mean rising heights and therefore, warming temperatures, mainly for areas away from the coast. Closer to the coast, flow off the cooler ocean waters will keep these areas a few degrees cooler than inland. With a southerly flow, dewpoints will also be on the rise. By the weekend, dewpoints could be in the lower 60s, making it slightly uncomfortable for some. The 00Z ECMWF and the 00Z GFS are in better agreement on the passage of a back door cold front late Saturday night into Sunday (quicker than previously forecast). Thereafter, the 2 models differ. The GFS continues to nose a strong high pressure from southeastern Canada into the area, while the ECMWF keeps this high off the Atlantic coast, and is weaker. Though the 00Z ECMWF does nose the high pressure farther inland than the previous run. The GFS solution would keep the area dry for the beginning of next week, while the ECMWF would keep it unsettled. Due to the uncertainty, a blend of models seems reasonable. The cold frontal passages Wednesday night looks to come through dry with limited moisture to work with. There may be some showers and thunderstorms with the warm frontal passage on Thursday, mainly inland as the lower temperatures over the coastal areas stabilizes those areas. A thermal trough sets up over inland areas for Friday and Saturday, which will mean diurnal showers and thunderstorms for these areas. Showers and thunderstorms will also be possible with the backdoor cold front passage late Sunday into Sunday night. This will not be a continuous rainfall event from Friday through Sunday night. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Isolated to scattered SHRA/TSRA will pass through the terminals through this evening. Will carry VCSH/VCTS in the 18Z TAFs through this evening, but confidence on timing and coverage is low. Generally a VFR forecast. Conds may briefly lower to MVFR in SHRA/TSRA. In addition, MVFR VSBY possible in areas of BR late tonight, mainly away from KNYC terminals. Winds generally ranging from N to NW at 5-10 KT. Winds become LGT/VRB this evening and tonight. ...NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http://www.weather.gov/zny/n90. KJFK TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KLGA TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KEWR TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KTEB TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. KHPN TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. KISP TAF Comments: Occasional SHRA/TSRA possible through this evening with brief MVFR conds. Low confidence on sea breeze development. .OUTLOOK FOR 18Z Wednesday through Sunday... .Wednesday through Thursday...VFR. .Thursday night through Friday morning...Occasional MVFR in showers/thunderstorms possible. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...VFR. && .MARINE... A weak pressure gradient force will be across the waters through Wednesday as a weakening low south of Cape Cod tracks to the northeast through tonight and high pressure builds in late tonight and Wednesday. The only hazard across the forecast waters will be isolated thunderstorms this afternoon into early this evening. Otherwise no hazardous conditions are expected. Winds and waves should remain below SCA criteria for the long term with light a pressure gradient. && .HYDROLOGY... Rainfall amounts of less than 1/4 inch are expected for the rest of today into this evening. Locally higher amounts will be possible in isolated thunderstorms. No concerns for hydrology Wednesday through Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP/MET NEAR TERM...JM/MET SHORT TERM...MET LONG TERM...JP AVIATION...MPS MARINE...JM/JP/MET HYDROLOGY...JP/MET
Area Forecast Discussion National Weather Service Albany NY 147 PM EDT TUE MAY 24 2016 .SYNOPSIS... Low pressure over southeast Long Island will bring scattered to numerous showers across our region from the Capital District south and east today with perhaps a rumble of afternoon thunder. Clouds will keep temperatures a little less warm than yesterday. This storm will move to our east tonight and high pressure will briefly build in through early Wednesday. A weak front will bring some showers and thunderstorms mainly north of the Capital region Wednesday afternoon. After that, a large Bermuda high will take hold of our weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 134 PM EDT...A closed off upper level low is located just southeast of the region off the coast of southern New England to the east of Long Island. Moisture wrapping around this feature continues to allow for some showers. The bulk of these have been occurring over southern Vermont and into adjacent Washington and Rensselaer Counties New York. Some parts of southern Vermont have seen locally around an inch of rainfall according to the latest MRMS precip estimation. Temps continue to vary from northwest to southeast across the area this afternoon. Thanks to partly to mostly sunny skies, some parts of the central/western Adirondacks have already reached into the mid 70s, while southern and eastern areas seeing lots of clouds remain only in the low 60s. Temps look to be fairly steady for the afternoon hours, with the warmest readings in northwest parts of the area. Most places from Albany on south/east won`t see much sun for the remainder of the day. The latest 16z 3km HRRR suggests that the threat for showers will remain in the forecast for this afternoon, mainly for areas east of the Hudson River. There might be enough instability with colder temperatures aloft for an isolated thunderstorm this afternoon, although most areas won`t see any thunder. Will continue with just a slight chance of thunder for much of the area. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... The cutoff low is forecast to drift east of Cape Cod tonight taking all the showers with it. Weak high pressure will build tonight into early Wednesday with a return to sunshine and higher temperatures back to 80-85 in the valleys, mid to upper 70s over the higher elevations. By afternoon, a weak back door front looks to slip southward into the Adirondacks touching off some scattered showers and possibly thunderstorms. One or two cells could make it south into the Capital region and even northern Catskills. A west to southwest wind 5-15 mph will become northwesterly during the afternoon. The front looks to washout by Wednesday night over the region as it slides to our south. Wednesday night looks dry with perhaps a little patchy fog as the wind will become light or calm overnight. Thursday will start out dry, but with increasing moisture, and perhaps a weak short wave, some scattered showers or thunderstorms could develop by afternoon across the region. These will be hit and miss with many areas likely not getting any rain at all. Otherwise, temperatures will climb in the mid or upper 80s in the valleys, 75-80 higher terrain. Dewpoints will reach the lower 60s in the Hudson valley south of Albany, mid or upper 50s further north so it will feel a little uncomfortably warm to some. && .LONG TERM /FRIDAY THROUGH MONDAY/... The extended forecast features above normal temperatures for the holiday weekend with chances of showers and thunderstorms each day. Friday-Friday night...the warm front finally moves through eastern NY and western New England during this time frame. A warm and humid air mass settles in...as dewpoints rise into the 60s. The boundary will likely be in the vicinity of the forecast area...and a weak short-wave in the west to southwest flow aloft will likely focus isolated to scattered showers and thunderstorms. The latest GFS20 has modest SBCAPEs in the 1000-2000 J/kg range, but the amount of deep shear remains uncertain. It is hard to ascertain if the convection will be severe this far out. H850 temps rise to +14C to +16C with highs in the lower to mid 80s in the valley locations...and mid 70s to around 80F over the mountains. The showers and thunderstorms should diminish quickly with the boundary retreating northward and the daytime heating gone. Lows will be upper 50s to lower 60s over most of the forecast area. Saturday-Saturday Night...The subtropical high builds in from the western Atlantic. The ALY forecast get into a warm sector. H850 temps nudge up to +15C to +17C on the latest ECMWF. PWATs increase to 1-1.5 inches. The GFS model soundings do not look very capped. Pop-up diurnally-driven showers and thunderstorms will be possible capable of heavy rainfall. The big question is the timing of the backdoor cold front from Northern New England and southeast Canada. The guidance varies on the timing and placement of the boundary. Our forecast reflects a timing more Saturday night into Sunday. Highs will be steamy for late May with humidity levels on the increase. Highs will be mainly in the mid and upper 80s for elevations at 1000 ft or lower...and upper 70s to lower 80s over the mountains. A slight to low chc of showers and thunderstorms will likely linger most of the night as the backdoor cold front dips south/southwest across the region. Sunday into Memorial Day...Temps look a bit cooler...closer to normal for late May on Sunday...as the backdoor cold front stalls over central NY...eastern PA and northern NJ. The ECMWF has H850 temps fall back to +10C to +12C from east to west over the forecast area...as the cold front moves through...and high pressure builds in from New Brunswick and Nova Scotia. There will continue to be solid chances of showers and thunderstorms as the cold front looks to move through. The amount of instability available will be the main issue for any strong to severe thunderstorms as the shear increases. This will continue to be monitored over the next several days. Highs on Sunday fall back into the mid 70s to lower 80s. Lows Sunday night fall back into the 50s to lower 60s. Memorial Day will feature a threat of a shower or thunderstorm...but it is uncertain where the frontal boundary goes. The latest WPC guidance has it move north into southern Quebec and Northern New England again. When a boundary is in the area with light to moderate amounts of instability and appreciable moisture...then a slight to low chc of showers and thunderstorms...especially in the afternoon will persist through the holiday weekend. Overall...it does not look like a washout at this point. After lows Sunday night in the 50s...highs will likely be in the 70s. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... Still some spokes of precipitation rotating around the low pressure system to our east. Have VCSH at all terminals for the afternoon. Not out of the question that a terminal could drop to MVFR conditions in a shower...or perhaps IFR...but chances are slight. Slight chances for TSRA this afternoon as well...but not sufficient to warrant mention in TAFs. So will maintain VFR at all terminals this afternoon. Question for tonight will be how much BR/FG form. All terminals will clear out tonight. Winds will be light. Best chances for FG are at KPSF where showers deposited around 0.2 inch of rain today. Have also included IFR conditions at KGFL in BR. At KALB and KPOU...MVFR in BR forecast. After BR/FG clears /by 12Z-13Z/ VFR conditions will prevail all terminals for Wednesday through 18z. Outlook... Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA...TSRA. Thursday Night: Moderate Operational Impact. Chance of SHRA. Friday: Moderate Operational Impact. Chance of SHRA...TSRA. Friday Night: Low Operational Impact. Slight Chance of SHRA...TSRA. Saturday: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Sunday: Moderate Operational Impact. Chance of SHRA...TSRA. && .FIRE WEATHER... RH levels should remain elevated today dropping not low than about 50 percent most places. There will be scattered to numerous showers mainly from the Capital region south and eastward. Most areas will likely not receive a quarter inch, except perhaps Litchfield county into the Mid Hudson valley and southern Catskills. The showers will move out tonight leaving us with a nearly fully recovery and likely the formation of dew as the wind will be light. Wednesday, will start out dry and sunny. A weak disturbance could trigger scattered showers and thunderstorms mainly north of the Capital region but a few could stray further south. A full recovery tonight as the showers move out followed by warm increasingly humid weather for the balance of the week. Low pressure tracking close to southern New England will scattered to numerous showers from the Capital region and perhaps an afternoon thunderstorm to locations from the Capital Region south and east. Weak high pressure will build east off the mid Atlantic states and summer like weather will spread across our region from the southwest through the end of next week. The surface wind will be light out of the north or northeast through Tuesday, generally 5-9 MPH becoming more west on Wednesday at 10 to 15 mph...with a few gusts near 20 mph possible in the afternoon. && .HYDROLOGY... No widespread hydrologic issues are anticipated through at least the next 5 days ending Friday. Unsettled weather is expected with some showers and scattered thunderstorms today. At this time amounts up to a tenth of an inch in our northwestern zones, to quarter to half an inch in our southeastern zones is anticipated. We do not expect this rainfall to produce much if any rises on rivers streams and reservoirs. There is another chance of showers and thunderstorms, mainly from Albany north on Wednesday with a backdoor cold front. More scattered showers and thunderstorms are possible Thursday when the weak cold front returns north. Any heavy rain in scattered thunderstorms would be very localized. 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...HWJIV NEAR TERM...Frugis/HWJIV/OKeefe SHORT TERM...HWJIV LONG TERM...Wasula AVIATION...OKeefe FIRE WEATHER...HWJIV HYDROLOGY...HWJIV/NAS
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
238 PM EDT WED MAY 25 2016 .SYNOPSIS... Issued at 111 PM EDT Wed May 25 2016 A weak trough moving through an unstable airmass over our area tonight is expected to cause scattered showers and thunderstorms. An upper level ridge will move into the area Thursday providing fair weather. Lows tonight will be in the mid 60s with highs Thursday in the lower and middle 80s. It will remain warm and humid through the Memorial Day weekend with chances for showers and thunderstorms continuing... though most of the weekend should be dry. && .SHORT TERM...(This Evening through Thursday) Issued at 235 PM EDT Wed May 25 2016 While ridging conts to dampen acrs the area...lack of discernible forcing and as yet poor mstr rtn hampering any notable precip dvlpmnt acrs the wrn lakes this aftn. MCV advg acrs nrn IA sprtg an arc of isold-sct convn fm ern MN into ne IA and the primary ftr of note shrt term as secondary MCV noted acrs se MO slides ewd through srn IN/nrn KY. 12Z ILX raob alludes to a general hostile environment aloft w/residual warm air in place although some cooling does take place further west twd DVN ahd of apchg mid lvl trough. Thus suspect newd advng ll theta-e ridge and wk ll flw will fail to produce any convn this aftn and have dropped all pop mention sans extreme west ahd of apchg mid lvl trough. Srn spoke of btr low-mid lvl forcing shld graze nw zones this evening and may yet sputter further se within modest theta-e ridge in place hwvr any sense of a consensus model solution sorely lacking. As such and in light of 12Z CAMS trends will sway fm prior likely pops overnight as primary focus aloft shifts up acrs nrn WI. In wake of this sys...largely subsident wrly ll flw overspreads the area on Thu and in light of 12Z mos guidance/trends fail to see any justification to carry a pop mention. && .LONG TERM...(Thursday Night through Wednesday) Issued at 235 PM EDT Wed May 25 2016 General wwd positioning of large scale upr trough and attendant sfc fntl zone points to lackluster chcs for organized rainfall through the pd. No doubt upstream convn w/potential downstream MCS influences complicate the picture...hwvr given stgr mean flw and deeper ll mstr plume remains well west invof of sfc fntl zone through the cntrl plains...it would be careless to embrace derived blended guidance pops which are clearly way overdone. Thus as yda will again cap any one pd to a low chc mention at this point. More fvrbl chcs may arise twd sun aftn/eve pending ewd extent and timing of robust wave lifting up through the midwest. Beyond that upr ridge cntrd ovr the wrn atl xpcd to expand nwd through dy7 and likely to cap off the local environment as new mean troughing dvlps through the wrn US. Otrws seasonably warm and humid conds xpcd through much of the pd. && .AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 111 PM EDT Wed May 25 2016 Moderate instability has developed over nrn IL this aftn along/ahead of a wk shrtwv/sfc trof. This system expected to move across nrn IN tonight. With just wk instability fcst across ne IN when the shrtwv moves through, just mentioned showers at FWA tonight, with contd mention of tstms at SBN where instability expected to be greater. Low level moistening overnight expected to result in brief mvfr cigs across the area Wed morning... mixing out by midday. && .IWX Watches/Warnings/Advisories... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...JT SHORT TERM...T LONG TERM...T AVIATION...JT Visit us at www.weather.gov/iwx Follow us on Facebook...Twitter...and YouTube at: www.facebook.com/NWSNorthernIndiana www.twitter.com/nwsiwx www.youtube.com/NWSNorthernIndiana
Area Forecast Discussion National Weather Service Indianapolis IN 101 PM EDT WED MAY 25 2016 .UPDATE... The AVIATION Section has been updated below. && .SYNOPSIS... Issued at 218 AM EDT Wed May 25 2016 Upper disturbances and an increasing moist and unstable atmosphere will combine to trigger thunderstorm chances today through early next week. Temperatures will remain a few degrees above normal through the period with highs mostly in the lower to mid 80s and lows in the 60s. && .NEAR TERM.../Today and Tonight/ Issued at 1007 AM EDT Wed May 25 2016 Pulled pops back a bit this morning and gradually ramped them up from midday onward per radar trends and HRRR input. Should see a gradual increase in convective coverage approach from the west this afternoon as the next upper level wave moves into the area and diurnal heating/destabilization is maximized. Remainder of forecast in good shape. Previous discussion follows. Issued at 218 AM EDT Wed May 25 2016 Focus for the near term will be on thunderstorm chances as well as temperatures. Models continue to be in excellent agreement on the major players with the 00z run. Currently...showers and thunderstorms were well southwest of our southwestern counties as a short wave slowly meanders over that area. This feature could still touch off a few storms overnight in that area and this morning a little further to the northeast. However...the main feature today is expected to be another upper wave moving through the southwest flow aloft...ejected northeast by a southern California upper low. This upper disturbance should move into our northwestern counties shortly after 21z per model blend...including the RAP. This feature will interact with an increasingly moist and unstable atmosphere...and modest 25 to 30 knot low level flow. Models are forecasting dew points in the lower 60s and mixed layer CAPEs to 1000 j/kg and higher this afternoon. This should be enough to touch off scattered thunderstorms across the forecast area. A few storms could be strong...but the SPC day1 outlook is keeping any severe risk just to our west in the even more unstable air. The thunderstorms should continue through the night as the upper wave moves through and with at least weak instability after sunset and a 25 to 30 knot low level jet. Will keep likely pops going far north...in closer proximity to the upper wave. Elsewhere...good chance pops look good. Should see plenty of convective clouds today but should still see enough sunshine peaking through from time to time to allow temperatures to reach the lower to mid 80s for afternoon highs. Meanwhile...with decent cloud cover and southerly winds staying up around 10 knots...prefer overnight lows at or slightly warmer than 00z MOS in the mid 60s. && .SHORT TERM.../Thursday through Friday night/ Issued at 218 AM EDT Wed May 25 2016 All eyes will continue to be on thunderstorm chances as the Socal upper low continues to send upper disturbances our way in the southwest flow aloft even as it moves to the Central Plains Friday night. Models have been very consistent with this and also with a modest but persistent moist Gulf flow through the Ohio Valley and lower Great Lakes on the back side of a Bermuda High and ahead of a slow moving to stalled Plains frontal system. Next disturbance in the southwest wavetrain is harder to pick out...but it looks like a weak impulse will move through the area Thursday afternoon. As the wave is more subtle...only went with 40 percent pops. However...models are showing a very unstable atmosphere with CAPES anywhere from 1500-3000 j/kg...depending on the model. So...with that kind of potential energy...could see some strong storms with a lot of cloud to ground lightning. Weaker dynamics preclude organized severe threat...however. After Thursday...the remainder of the forecast looks pretty much the same. Although models have a harder time resolving any weak impulse that far out...each period should see at least one weak wave and with the atmosphere remaining moist and unstable...will keep 30-40 percent pops going the rest of the way. It will remain warm and humid and with the air mass unchanged...will go with a persistence forecast with highs in the mid 80s and lows in the mid and upper 60s. && .LONG TERM /Saturday through next Tuesday/... Issued at 222 AM EDT Wed May 25 2016 Ensembles in good agreement with respect to the overall pattern during the extended. Mean ridging expected over the eastern parts of the country with troughing over the west. An upper disturbance is expected to eject into the western Great Lakes over the upcoming weekend. Will keep chance PoPs in the forecast for Saturday and Sunday to cover the passage of this trough. By early next week, convective potential may tend to diminish and become more diurnal in nature as heights rise some, however ensembles suggest a weakness in the upper ridge/cool pocket may linger over the Ohio valley. For this reason, will continue to keep some PoPs going through early next week. && .AVIATION /Discussion for the 251800z tafs/... Issued at 1251 PM EDT Wed May 25 2016 Mainly VFR conditions are expected this TAF period. Brief MVFR conditions will be possible with any TSRA that may occur this afternoon and evening. GFS suggests a weak short wave over Illinois to progress across indiana late this afternoon and evening. Forecast soundings suggest steep lapse rates with large CAPE. Thus expect sct TSRA to develop along and ahead of the wave during the max heating hours this afternoon and evening. Uncertainty remains with precise timing and will update to prevailing as showers and storms develop. Patchy Fog may be possible late tonight...particularly in those areas that get rain. Have included MVFR fog at the TAF sites for now. A lull in convective activity is expected on Thursday morning as Indiana should remain between short waves. Time heights suggest subsidence and forecast soundings are capped through at least 18z. && .IND Watches/Warnings/Advisories... NONE. && $$ SYNOPSIS...MK NEAR TERM...MK/NIELD SHORT TERM...MK LONG TERM...JAS AVIATION...JP
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
101 PM CDT WED MAY 25 2016 ...Update to aviation forecast discussion... .SHORT TERM...(Today and Tonight) Issued at 415 AM CDT WED MAY 25 2016 At 4 AM Wednesday morning, a large thunderstorm complex continued to progress east out of the area. A well-developed MCV was present in northern parts of this storm complex over far SE Nebraska while a wake low has developed on the back side. This wake low has been producing gusts up to 50 mph and will continue to do so as it moves east although it would seem likely to be near its peak intensity right now. Additional convective showers and storms were developing in the convergence zone into east central KS, but this area has been well worked over and do not anticipate anything more than a few pockets of heavy rain in this area. Another area of thunderstorms has been persistently developing in association with the LLJ near the KS/NE border in north central KS. This area of development is likely to gradually push a weak cold pool a bit south with development progressively into northern and northeast KS. However, it will also be making its way into an area of lesser instability with the effective convective overturning from early this morning, and expect the storm development to be sub-severe and any associated outflow likely not very strong. As the day goes on, the forecast will once again be complex but there are at least a few moderate confidence elements to grasp on to in making the forecast. The first is the outflow incoming from the north which should set up east to west across the area and then wash out by mid to late afternoon...although some semblance of it may remain through late day. The second feature of interest has been consistently forecast by models over the past few days, and that is a slightly veered flow owing to the passage of a rather strong short wave early this morning. This veered flow will cause the dryline to surge east with a dryline bulge into eastern KS. Most indications are that this dryline bulge will focus into the local forecast area, probably over the Flint Hills region just west of Emporia and south of Manhattan. An area of surface low pressure is also expected to develop into this area. So, as the afternoon progresses, expect effective heating to lead to a rather unstable airmass across the forecast area. This instability is likely to be capped for much of the day though as those veered winds aloft will bring a slightly stronger EML into the local area. What this all leads to is a conditional forecast for severe thunderstorms. The main question will be if the cap can be broken with only nebulous large scale lifting mechanisms (and even some potential for weak subsidence aloft), and only modest convergence along the dryline. IF thunderstorms are able to develop, it would be in a very unstable environment with effective shear in the 35-40 kt range which would be more than sufficient for supercells. It also seems that if storms develop they would remain relatively discrete owing to the convective inhibition, and would probably not develop until peak heating. Thus, any storms that are able to develop can be expected to become severe with very large hail and locally damaging winds possible. Veered low level winds are not particularly supportive of tornadoes, but the potential of a weak remnant outflow boundary along with localized backing depending on the strength of the surface meso-low in central KS means there is at least some tornado potential with any long-lived supercell structures. The best chance for initiation would be along the nose of that dryline bulge with storm motion being almost due east. Later tonight, convective coverage is in question, and it may focus an area of development over far northeast KS where the LLJ convergence maximizes in an unstable airmass. If this occurs, could see areas of heavy rain as well as a continued severe weather threat through the overnight hours. .LONG TERM...(Thursday through Tuesday) Issued at 415 AM CDT WED MAY 25 2016 Main focus for the period in terms of severe weather chances reside on Thursday afternoon and then on Friday afternoon as the open trough axis lifts through the central plains. Exact details on location and timing of convection is still uncertain and dependent on Wednesday night convection and how quickly it clears which currently appears during the morning hours. With the system becoming more negatively tilted during the afternoon on Thursday, winds aloft are expected to increase while sfc winds back towards the south and southeast as the sfc low stretches across central KS. The dryline is the likely trigger for convection to fire in central KS by late afternoon. These storms are expected to track eastward towards north central KS during the evening. Second area for possible convection is along the expected outflow boundary draped over the area from previous convection. With ample moisture and available CAPE in excess of 4000 J/KG, it will not take much forcing to initiate development. By the evening, LLJ increases with a cluster of storms to center around the warm front near the KS and NE border. These storms are likely to impact much of the area as the low level jet veers overnight. Main threats are large hail and damaging winds. Tornadoes are possible as well, especially with any discrete cells or in vicinity to a boundary through early evening. Localized flash flooding is likely given the excessive rainfall these past few days. By Friday, upper level dynamics increases as the trough lifts over central KS, becoming more stacked with the sfc low and attendant dryline. The dryline is expected to shift east into the CWA, creating another a decent chance for thunderstorms to develop in the late afternoon and evening. Shear profiles are sufficient to once again see all modes of severe weather with decent low level shear profiles in the early evening near the sfc low over north central KS. Highlights for the weekend into mid next week do not change much from previous forecasts. As upper trough exits northeast Saturday afternoon, could see additional storms in afternoon. Severe weather is unlikely as effective shear is pretty weak, less than 20 kts. Similar scenario is likely from Sunday onward as broad southwest troughing continues to bring disturbances into the area. Flash Flooding and River Flooding threats are very high through the weekend. Rainfall totals through the weekend range from 1-4 inches or more through Sunday. With little change in airmass, scattered thunderstorms are possible for each period until perhaps Wednesday when a cool front may finally bring a relief from the rainfall. && .AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 1257 PM CDT WED MAY 25 2016 Outflow boundary from earlier thunderstorms along the Kansas river at noon time, very near TAF sites. Ceilings should rise to VFR shortly, while winds could be variable for the next 2 or 3 hours, particularly at TOP and FOE before the boundary moves back north. Isolated thunderstorms developing over central KS late this afternoon may move through or near TAF sites by early evening so have VCTS for a few hours during that time. Later tonight, moist airmass could allow fog to form. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Barjenbruch LONG TERM...Prieto AVIATION...GDP
  [top] Area Forecast Discussion National Weather Service Wichita KS 1247 PM CDT WED MAY 25 2016 .SYNOPSIS... Issued at 350 AM CDT Wed May 25 2016 Numerous thunderstorms containing torrential rains continue across Butler, Cowley & Elk Counties at 230 AM where Flood & Flash Flood Warnings are in effect. Thunderstorms are being sustained by strong lower-deck theta-e advection enhanced by lift induced by mid-level shortwave sprinting NE across SE KS. Hourly rainfalls are in the 1 to 3 inch range in extreme Ern Sumner & NW Cowley Counties. The cloud-to-ground lightning continues to be frequent & dangerous. && .SHORT TERM...(Today through Friday night) Issued at 350 AM CDT Wed May 25 2016 Forecast Highlight: More severe thunderstorms possible for SE KS this afternoon & this evening. Significant threat for severe thunderstorms with large-very large hail, winds around 70 mph & tornadoes continues for areas primarily along & W of I35-I/135 Thu Afternoon & Night. Today & Tonight: With the afore-mentioned mid-level shortwave continuing to sprint NE across the Mid & Upr MS Valley thunderstorms would be greatest across SE KS where aligned with broad ultra-high octane moisture axis. Deep-layer shear, more so directional, remains impressive & with very high instability there`s a continued threat for severe thunderstorms for SE KS both this afternoon & tonight. Thu & Thu Night: The greatest threat for significant severe thunderstorms is still expected for areas along, and W, of I-35/I-135. A deep upper-deck trof that`ll push slowly E across AZ & NM will undergo cyclogenesis as it lifts SLOWLY NE to NE NM, the TX & OK Panhandles & the CO/KS border. This would induce increased deep-layer ascent over the Wrn Plains that would transition E toward Central KS. The slow NE lift of the upper low would of course induce pronounced sfc cyclogenesis over SE CO & Wrn KS on Thu. This would strengthen the lower-mid level moist advection across KS with the most pronounced advection targeting Central parts of OK & KS. This time deep-layer speed shear would be strong & coupled with respectable directional shear supercells would once erupt over these areas & move NE. The supercells should arrive areas along & W of I-35/I-135 late Thu Afternoon & continue thru the night. SPC has expanded the "Enhanced Risk" N as far as Srn Nebraska. As such "Severe Thunderstorms With Large Hail And Damaging Winds" have been assigned to the afore- mentioned areas. Fri & Fri Night: The threat for severe thunderstorms is beginning to increase Fri Afternoon & Evening. The greatest severe threat would shift slowly E. For now SPC has assigned "Slight Risk" to E TX & SE OK, but wouldn`t be surprised if the "Slight Risk" assignment is eventually spread N across Central & Ern KS. Stay tuned. .LONG TERM...(Saturday through Tuesday) Issued at 350 AM CDT Wed May 25 2016 For Sat & Sat Night the GFS & ECMWF continue to agree quite well with overall pattern, although the ECMWF is bit stronger with the departing upper-deck shortwave, scheduled to reach the Upper MS Valley Sat Night. A 2nd upper-deck trof is forecast to move E & like it`s predecessor it`ll move slowly E & strengthen as it digs across Srn CA. A "lead" shortwave will eject NE, likely reaching Wrn OK & Wrn KS Sun Afternoon. As such, there`ll be several rounds of thunderstorms from Sun Afternoon thru next Tue. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1240 PM CDT Wed May 25 2016 convective potential is the main challenge. Anticipate conditions will improve to vfr at all sites early this afternoon. Thunderstorms possible in the vicinity of KSLN/KHUT/kgdb/KICT late afternoon/early evening near dryline/outflow boundary. KCNU looks to remain well into the stable area of the outflow boundary. Suspect thunderstorms will be primarily focused by surface convergence. Given soupy airmasss, anticipate MVFR/IFR conditions to return later tonight. -Howerton && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 89 70 87 67 / 10 10 40 50 Hutchinson 89 67 87 66 / 10 10 50 50 Newton 89 69 86 66 / 20 20 40 50 ElDorado 88 70 86 67 / 20 20 30 50 Winfield-KWLD 89 71 87 67 / 20 10 40 50 Russell 89 61 88 62 / 20 10 40 50 Great Bend 89 61 88 63 / 10 10 50 40 Salina 90 67 89 66 / 20 20 40 50 McPherson 89 68 87 66 / 20 10 40 50 Coffeyville 86 71 86 68 / 50 20 30 50 Chanute 86 71 86 67 / 40 20 30 50 Iola 85 71 86 67 / 50 20 30 60 Parsons-KPPF 86 71 86 68 / 50 20 30 50 && .ICT Watches/Warnings/Advisories... None. && $$ SYNOPSIS...EPS SHORT TERM...EPS LONG TERM...EPS AVIATION...PJH
Area Forecast Discussion National Weather Service Goodland KS 1139 AM MDT WED MAY 25 2016 .UPDATE... Issued at 1139 AM MDT Wed May 25 2016 With low cloud deck still impacting central portions of the forecast area...have lowered expected high temps by a few degrees to account for the lack of decreasing areal coverage. No other changes at this time. && .SHORT TERM...(Today through Friday night) Issued at 242 AM MDT Wed May 25 2016 Upper flow will be southwest today/tonight ahead of an upper low that will move into the 4-corners areas Thursday. The upper low will move into eastern Colorado Thursday night. The low then moves into northwest Kansas Friday and into north central Kansas Friday night. A surface trough will be over northwest Kansas today and tonight. A surface low will organize over southeast Colorado Thursday. The surface low will move into northwest Kansas Friday and then into north central kansas Friday night. Subsidence will move into the fa this morning behind the exiting wave. By this afternoon, some lift will develop over an axis of instability where there will be a slight chance of storms. Any storms will move northeast with subsidence returning to the fa early this evening. Late this evening another shortwave will produce some lift across the northern fa for storms overnight. Storms will be possible early Thursday and continue Thursday night and Friday. Dynamics and moisture favor the northwest fa during this time. By Friday night the focus for storms shifts over the eastern fa as the low moves east. Shear and cape are both supportive of severe storms through Friday. Shear and cape drop off Friday night so that there should be no severe threat and that thunder will be isolated with showers the dominant type of weather. STRATUS AND PATCHY FOG HAVE MOVED INTO THE FA EARLY THIS MORNING. NAM BOUNDARY LAYER RH POINTS OUT THE EXTENT OF THE STRATUS ACROSS THE FA. CONDITIONS SHOULD IMPROVE BY MID MORNING. Max temperatures should reach the lower 80s today. Cooler readings can be expected Thursday ranging from the lower 70s in eastern Colorado to the lower 80s in the eastern fa. Max temperatures Friday should range from the mid 60s to the mid 70s. Min temperatures should be in the lower to mid 50s with some upper 40s in eastern Colorado. .LONG TERM...(Saturday through Tuesday) Issued at 242 AM MDT Wed May 25 2016 At the start of the extended mid level ridging will allow for periods of dry conditions heading into Saturday. Starting Saturday night and going through the end of the extended period, expect an increase chance of rain showers and thunderstorms as shortwaves will move around the base of approaching upper level low over the Pacific Northwest/Northern Rockies area. Temperatures will be in the near to above normal range during the extended period with highs mainly in the mid to upper 70s, with some areas reaching the lower 80s. Overnight lows will range in the 50s with some upper 40s in Northeastern Colorado. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1128 AM MDT Wed May 25 2016 For KGLD...Mainly VFR conditions after 20z-21z. MVFR skies thru 20z-21z...and 3-5sm -shra br from 04z-08z Thursday. Winds...Variable from the NW thru 21z then SSE 5-10kts...becoming ENE around 5kts by 08z Thursday as front approaches. For KMCK...Mainly VFR conditions...w/ some MVFR from 04z-09z thursday w/ 3-5sm -shra br. Winds ESE around 10kts thru 00z Thursday...then ENE 5-10kts. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...FS LONG TERM...BW AVIATION...JN
Area Forecast Discussion National Weather Service Dodge City KS 712 AM CDT WED MAY 25 2016 ...updated aviation section... .SHORT TERM...(Today and tonight) Issued at 424 AM CDT Wed May 25 2016 Quiet weather is likely in southwest Kansas today after the major severe weather outbreak Tuesday afternoon and evening. An outflow boundary from the convective cluster in eastern Kansas extended from south of Medicine Lodge across southwest Kansas into east central Colorado early this morning, and an area of surface low pressure was centered near the Colorado/Kansas border south of GLD. A vigorous upper level trough was evident on satellite imagery from eastern Montana into eastern Colorado at 08Z. The surface low should move east into north central Kansas as the upper level trough progresses into the eastern Dakotas later today, and low level flow will become southwest as the convective outflow erodes this morning. Low level moisture will erode during the day, and a dryline will become established across central Kansas this afternoon. A minor upper level trough approaching the Four Corners area will move into northwest Kansas and southern Nebraska this afternoon, and a few thunderstorms may develop in the richer low level moisture north of the surface cyclone in northern Kansas. Other thunderstorms can be expected near the dryline across central Kansas. Downslope flow, clearing skies and drier low level air will allow temperatures this afternoon to rise into the 80s and lower 90s with the warmest temperatures in the southwest corner of the state. Temperatures will be modulated downward slightly in areas that received heavy rainfall Tuesday as a consequence of evaporation of ponded water. Mostly clear skies and relatively dry air will allow temperatures tonight to fall back to near seasonal averages in the 50s and lower 60s. An upper level cyclone centered near the coast of southern California this morning will eject northeast as another upper level trough near the British Columbia coast drops into the western United States long wave position. This upper level cyclone should reach eastern Colorado Friday morning. Surface cyclogenesis will occur in southeast Colorado Thursday as the upper level cyclone approaches, and low level flow in western Kansas will back and increase as pressures fall in southeast Colorado. Low level moisture will surge back into southwest Kansas, but some uncertainty exists about exactly where the dryline will become established Thursday afternoon. The current guidance suggests that the rich low level moisture will spread back at least as far west as Dodge City. Increasing mid and upper level flow over the rich moisture east of the dryline will provide an environment favorable for development of supercell thunderstorms with all of the attendant severe weather phenomena again Thursday, especially from Dodge City east. Mesoscale details will become better defined later, but the potential exists for another outbreak of severe weather with a few tornadoes Thursday afternoon and evening. .LONG TERM...(Thursday through Tuesday) Issued at 424 AM CDT Wed May 25 2016 The upper level cyclone that moves into eastern Colorado Friday morning will progress slowly across western Kansas into eastern Nebraska by Saturday morning. The GFS is quicker to eject the upper level cyclone than the ECMWF and GEM. Given the very blocky pattern with an upper level cyclone in central Canada, the slower solution advertised by the ECMWF seems more reasonable. A diffuse surface cyclone should move slowly into central Kansas Friday afternoon with a weak Pacific cold front extending into the Texas Panhandle. Cold air aloft with the upper level cyclone will provide sufficient instability for thunderstorm development across much of Kansas Friday. Temperature Friday will be cooler as a consequence of cloud cover wrapping around the surface cyclone. Weak ridging behind the upper level trough should keep Saturday quiet, but another upper level trough rotating around the western United States mean long wave trough will approach Kansas on Sunday and support more thunderstorms. Another minor trough should approach on Monday. Weaker flow should reduce the potential for significant severe weather, but there may be some threat of severe weather each day. Upper level ridging should build over the Rockies the first part of next week, and a cold front will move across Kansas Tuesday or Tuesday night as a progressive upper level trough moves across the Northern Plains and digs toward the Great Lakes. There may be a few days of meteorologically benign weather next week with north to northwest anticyclonic flow aloft over the High Plains. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 707 AM CDT Wed May 25 2016 Fog development at DDC and GCK should rapidly diminish this morning as the surface warms. VFR can then be expected for the rest of the TAF period once the thin stratus layer also completely erodes. Convection is not expected today as the dryline advances further east. && .HYDROLOGY... Issued at 424 AM CDT Wed May 25 2016 Widespread rainfall estimated by radar to be from three to five inches in northern Pratt and southern Stafford Counties likely has resulted in considerable ponding of surface water. Law enforcement has not reported any significant problems with runoff, and the soil in that area is sandy and should absorb much of the water. An areal flood warning will be maintained this morning. Other heavy rainfall occurred from Edwards County into Pawnee County and in eastern Lane and western Ness Counties. Although some small streams likely will be running high, major flooding is unlikely. && .PRELIMINARY POINT TEMPS/POPS... DDC 89 57 88 57 / 0 10 40 40 GCK 90 52 88 53 / 0 10 20 30 EHA 90 54 86 51 / 0 0 10 20 LBL 91 54 89 54 / 0 10 20 20 HYS 87 57 85 60 / 0 0 40 40 P28 90 66 88 64 / 0 0 30 40 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Ruthi LONG TERM...Ruthi AVIATION...Russell HYDROLOGY...Ruthi
Area Forecast Discussion National Weather Service Wichita KS 658 AM CDT WED MAY 25 2016 .SYNOPSIS... Issued at 350 AM CDT Wed May 25 2016 Numerous thunderstorms containing torrential rains continue across Butler, Cowley & Elk Counties at 230 AM where Flood & Flash Flood Warnings are in effect. Thunderstorms are being sustained by strong lower-deck theta-e advection enhanced by lift induced by mid-level shortwave sprinting NE across SE KS. Hourly rainfalls are in the 1 to 3 inch range in extreme Ern Sumner & NW Cowley Counties. The cloud-to-ground lightning continues to be frequent & dangerous. && .SHORT TERM...(Today through Friday night) Issued at 350 AM CDT Wed May 25 2016 Forecast Highlight: More severe thunderstorms possible for SE KS this afternoon & this evening. Significant threat for severe thunderstorms with large-very large hail, winds around 70 mph & tornadoes continues for areas primarily along & W of I35-I/135 Thu Afternoon & Night. Today & Tonight: With the afore-mentioned mid-level shortwave continuing to sprint NE across the Mid & Upr MS Valley thunderstorms would be greatest across SE KS where aligned with broad ultra-high octane moisture axis. Deep-layer shear, more so directional, remains impressive & with very high instability there`s a continued threat for severe thunderstorms for SE KS both this afternoon & tonight. Thu & Thu Night: The greatest threat for significant severe thunderstorms is still expected for areas along, and W, of I-35/I-135. A deep upper-deck trof that`ll push slowly E across AZ & NM will undergo cyclogenesis as it lifts SLOWLY NE to NE NM, the TX & OK Panhandles & the CO/KS border. This would induce increased deep-layer ascent over the Wrn Plains that would transition E toward Central KS. The slow NE lift of the upper low would of course induce pronounced sfc cyclogenesis over SE CO & Wrn KS on Thu. This would strengthen the lower-mid level moist advection across KS with the most pronounced advection targeting Central parts of OK & KS. This time deep-layer speed shear would be strong & coupled with respectable directional shear supercells would once erupt over these areas & move NE. The supercells should arrive areas along & W of I-35/I-135 late Thu Afternoon & continue thru the night. SPC has expanded the "Enhanced Risk" N as far as Srn Nebraska. As such "Severe Thunderstorms With Large Hail And Damaging Winds" have been assigned to the afore- mentioned areas. Fri & Fri Night: The threat for severe thunderstorms is beginning to increase Fri Afternoon & Evening. The greatest severe threat would shift slowly E. For now SPC has assigned "Slight Risk" to E TX & SE OK, but wouldn`t be surprised if the "Slight Risk" assignment is eventually spread N across Central & Ern KS. Stay tuned. .LONG TERM...(Saturday through Tuesday) Issued at 350 AM CDT Wed May 25 2016 For Sat & Sat Night the GFS & ECMWF continue to agree quite well with overall pattern, although the ECMWF is bit stronger with the departing upper-deck shortwave, scheduled to reach the Upper MS Valley Sat Night. A 2nd upper-deck trof is forecast to move E & like it`s predecessor it`ll move slowly E & strengthen as it digs across Srn CA. A "lead" shortwave will eject NE, likely reaching Wrn OK & Wrn KS Sun Afternoon. As such, there`ll be several rounds of thunderstorms from Sun Afternoon thru next Tue. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 658 AM CDT Wed May 25 2016 Expect some scattered MVFR CIGS in the wake of the overnight convective complex. This will lead to some of the lowest CIGS near KRSL, KGBD and KRSL. Expect the low clouds to dissipate later this morning with VFR conditions returning to most locations for the afternoon hours. Will also see some lingering SHRA/TSRA in SE KS as the complex of storms exits the area this morning. For the afternoon hours, expect a dry line/boundary to push to near the KS Turnpike late this afternoon. Could see isolated convection develop along and east of this boundary for the late afternoon and evening hours. Think most of the convection will develop well to the east of the KICT TAF, so will not mention it in KICT just yet. But will mention it for most of the evening hours for the KCNU Taf with the isolated storms expected to congeal into a forward propagating complex of storms that will move east into Wrn MO early on Thu. Ketcham && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 89 70 87 67 / 10 10 40 50 Hutchinson 89 67 87 66 / 10 10 50 50 Newton 89 69 86 66 / 20 20 40 50 ElDorado 88 70 86 67 / 20 20 30 50 Winfield-KWLD 89 71 87 67 / 20 10 40 50 Russell 89 61 88 62 / 20 10 40 50 Great Bend 89 61 88 63 / 10 10 50 40 Salina 90 67 89 66 / 20 20 40 50 McPherson 89 68 87 66 / 20 10 40 50 Coffeyville 86 71 86 68 / 50 20 30 50 Chanute 86 71 86 67 / 40 20 30 50 Iola 85 71 86 67 / 50 20 30 60 Parsons-KPPF 86 71 86 68 / 50 20 30 50 && .ICT Watches/Warnings/Advisories... None. && $$ SYNOPSIS...EPS SHORT TERM...EPS LONG TERM...EPS AVIATION...BDK
Area Forecast Discussion National Weather Service Goodland KS 516 AM MDT WED MAY 25 2016 .SHORT TERM...(Today through Friday night) Issued at 242 AM MDT Wed May 25 2016 Upper flow will be southwest today/tonight ahead of an upper low that will move into the 4-corners areas Thursday. The upper low will move into eastern Colorado Thursday night. The low then moves into northwest Kansas Friday and into northcentral Kansas Friday night. A surface trough will be over northwest Kansas today and tonight. A surface low will organize over southeast Colorado Thursday. The surface low will move into northwest Kansas Friday and then into northcentral kansas Friday night. Subsidence will move into the fa this morning behind the exiting wave. By this afternoon, some lift will develop over an axis of instability where there will be a slight chance of storms. Any storms will move northeast with subsidence returning to the fa early this evening. Late this evening another shortwave will produce some lift across the northern fa for storms overnight. Storms will be possible early Thursday and continue Thursday night and Friday. Dynamics and moisture favor the northwest fa during this time. By Friday night the focus for storms shifts over the eastern fa as the low moves east. Shear and cape are both supportive of severe storms through Friday. Shear and cape drop off Friday night so that there should be no severe threat and that thunder will be isolated with showers the dominant type of weather. STRATUS AND PATCHY FOG HAVE MOVED INTO THE FA EARLY THIS MORNING. NAM BOUNDARY LAYER RH POINTS OUT THE EXTENT OF THE STRATUS ACROSS THE FA. CONDITIONS SHOULD IMPROVE BY MID MORNING. Max temperatures should reach the lower 80s today. Cooler readings can be expected Thursday ranging from the lower 70s in eastern Colorado to the lower 80s in the eastern fa. Max temperatures Friday should range from the mid 60s to the mid 70s. Min temperatures should be in the lower to mid 50s with some upper 40s in eastern Colorado. .LONG TERM...(Saturday through Tuesday) Issued at 242 AM MDT Wed May 25 2016 At the start of the extended mid level ridging will allow for periods of dry conditions heading into Saturday. Starting Saturday night and going through the end of the extended period, expect an increase chance of rainshowers and thunderstroms as shortwaves will move around the base of approaching upper level low over the Pacific Northwest/Northern Rockies area. Temperatures will be in the near to above normal range during the extended period with highs mainly in the mid to upper 70s, with some areas reaching the lower 80s. Overnight lows will range in the 50s with some upper 40s in Northeastern Colorado. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 508 AM MDT Wed May 25 2016 LIFR CONDITIONS AT KGLD SHOULD IMPROVE AROUND 15Z AS WINDS TURN NORTHWEST. OTHERWISE CONDITIONS SHOULD BE VFR AT KGLD AND KMCK FOR THE NEXT 24 HOURS WITH ONLY A SLIGHT CHANCE OF STORMS AT KMCK THIS AFTERNOON. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...BW AVIATION...FS
Area Forecast Discussion National Weather Service Wichita KS 350 AM CDT WED MAY 25 2016 .SYNOPSIS... Issued at 350 AM CDT Wed May 25 2016 Numerous thunderstorms containing torrential rains continue across Butler, Cowley & Elk Counties at 230 AM where Flood & Flash Flood Warnings are in effect. Thunderstorms are being sustained by strong lower-deck theta-e advection enhanced by lift induced by mid-level shortwave sprinting NE across SE KS. Hourly rainfalls are in the 1 to 3 inch range in extreme Ern Sumner & NW Cowley Counties. The cloud-to-ground lightning continues to be frequent & dangerous. && .SHORT TERM...(Today through Friday night) Issued at 350 AM CDT Wed May 25 2016 Forecast Highlight: More severe thunderstorms possible for SE KS this afternoon & this evening. Significant threat for severe thunderstorms with large-very large hail, winds around 70 mph & tornadoes continues for areas primarily along & W of I35-I/135 Thu Afternoon & Night. Today & Tonight: With the afore-mentioned mid-level shortwave continuing to sprint NE across the Mid & Upr MS Valley thunderstorms would be greatest across SE KS where aligned with broad ultra-high octane moisture axis. Deep-layer shear, more so directional, remains impressive & with very high instability there`s a continued threat for severe thunderstorms for SE KS both this afternoon & tonight. Thu & Thu Night: The greatest threat for significant severe thunderstorms is still expected for areas along, and W, of I-35/I-135. A deep upper-deck trof that`ll push slowly E across AZ & NM will undergo cyclogenesis as it lifts SLOWLY NE to NE NM, the TX & OK Panhandles & the CO/KS border. This would induce increased deep-layer ascent over the Wrn Plains that would transition E toward Central KS. The slow NE lift of the upper low would of course induce pronounced sfc cyclogenesis over SE CO & Wrn KS on Thu. This would strengthen the lower-mid level moist advection across KS with the most pronounced advection targeting Central parts of OK & KS. This time deep-layer speed shear would be strong & coupled with respectable directional shear supercells would once erupt over these areas & move NE. The supercells should arrive areas along & W of I-35/I-135 late Thu Afternoon & continue thru the night. SPC has expanded the "Enhanced Risk" N as far as Srn Nebraska. As such "Severe Thunderstorms With Large Hail And Damaging Winds" have been assigned to the afore- mentioned areas. Fri & Fri Night: The threat for severe thunderstorms is beginning to increase Fri Afternoon & Evening. The greatest severe threat would shift slowly E. For now SPC has assigned "Slight Risk" to E TX & SE OK, but wouldn`t be surprised if the "Slight Risk" assignment is eventually spread N across Central & Ern KS. Stay tuned. .LONG TERM...(Saturday through Tuesday) Issued at 350 AM CDT Wed May 25 2016 For Sat & Sat Night the GFS & ECMWF continue to agree quite well with overall pattern, although the ECMWF is bit stronger with the departing upper-deck shortwave, scheduled to reach the Upper MS Valley Sat Night. A 2nd upper-deck trof is forecast to move E & like it`s predecessor it`ll move slowly E & strengthen as it digs across Srn CA. A "lead" shortwave will eject NE, likely reaching Wrn OK & Wrn KS Sun Afternoon. As such, there`ll be several rounds of thunderstorms from Sun Afternoon thru next Tue. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1130 PM CDT Tue May 24 2016 Evolving mesoscale convective system over central Kansas will move east overnight with brief periods of IFR/MVFR VSBYS in heavy rain and strong, gusty winds. Some MVFR CIGS can also be expected Wednesday morning. A moist south to southeast wind will continue on Wednesday and become gusty along and east of the I-135 corridor. Some late day convection is also possible though probably more isolated in nature. KED && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 89 70 87 67 / 10 10 40 50 Hutchinson 89 67 87 66 / 10 10 50 50 Newton 89 69 86 66 / 20 20 40 50 ElDorado 88 70 86 67 / 20 20 30 50 Winfield-KWLD 89 71 87 67 / 20 10 40 50 Russell 89 61 88 62 / 20 10 40 50 Great Bend 89 61 88 63 / 10 10 50 40 Salina 90 67 89 66 / 20 20 40 50 McPherson 89 68 87 66 / 20 10 40 50 Coffeyville 86 71 86 68 / 50 20 30 50 Chanute 86 71 86 67 / 40 20 30 50 Iola 85 71 86 67 / 50 20 30 60 Parsons-KPPF 86 71 86 68 / 50 20 30 50 && .ICT Watches/Warnings/Advisories... None. && $$ SYNOPSIS...EPS SHORT TERM...EPS LONG TERM...EPS AVIATION...KED
Area Forecast Discussion National Weather Service Goodland KS 246 AM MDT WED MAY 25 2016 .SHORT TERM...(Today through Friday night) Issued at 242 AM MDT Wed May 25 2016 Upper flow will be southwest today/tonight ahead of an upper low that will move into the 4-corners areas Thursday. The upper low will move into eastern Colorado Thursday night. The low then moves into northwest Kansas Friday and into northcentral Kansas Friday night. A surface trough will be over northwest Kansas today and tonight. A surface low will organize over southeast Colorado Thursday. The surface low will move into northwest Kansas Friday and then into northcentral kansas Friday night. Subsidence will move into the fa this morning behind the exiting wave. By this afternoon, some lift will develop over an axis of instability where there will be a slight chance of storms. Any storms will move northeast with subsidence returning to the fa early this evening. Late this evening another shortwave will produce some lift across the northern fa for storms overnight. Storms will be possible early Thursday and continue Thursday night and Friday. Dynamics and moisture favor the northwest fa during this time. By Friday night the focus for storms shifts over the eastern fa as the low moves east. Shear and cape are both supportive of severe storms through Friday. Shear and cape drop off Friday night so that there should be no severe threat and that thunder will be isolated with showers the dominant type of weather. STRATUS AND PATCHY FOG HAVE MOVED INTO THE FA EARLY THIS MORNING. NAM BOUNDARY LAYER RH POINTS OUT THE EXTENT OF THE STRATUS ACROSS THE FA. CONDITIONS SHOULD IMPROVE BY MID MORNING. Max temperatures should reach the lower 80s today. Cooler readings can be expected Thursday ranging from the lower 70s in eastern Colorado to the lower 80s in the eastern fa. Max temperatures Friday should range from the mid 60s to the mid 70s. Min temperatures should be in the lower to mid 50s with some upper 40s in eastern Colorado. .LONG TERM...(Saturday through Tuesday) Issued at 242 AM MDT Wed May 25 2016 At the start of the extended mid level ridging will allow for periods of dry conditions heading into Saturday. Starting Saturday night and going through the end of the extended period, expect an increase chance of rainshowers and thunderstroms as shortwaves will move around the base of approaching upper level low over the Pacific Northwest/Northern Rockies area. Temperatures will be in the near to above normal range during the extended period with highs mainly in the mid to upper 70s, with some areas reaching the lower 80s. Overnight lows will range in the 50s with some upper 40s in Northeastern Colorado. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1100 PM MDT Tue May 24 2016 For KGLD...vfr conditions expected through 8z with winds from the southeast at 10 mph quickly shifting to the southwest. From 9z through 14z stratus expected with visibilities possibly down to 2sm creating mvfr conditions with winds from the west then northwest under 10 mph. Cigs improve to vfr by 15z with only a few clouds at best for the rest of the taf period. Winds expected from the north 5-10kts around 18z then back all the way around to the east-southeast for the remainder of the taf period. For KMCK...vfr conditions expected through 7z with cigs and vis lowering to mvfr/ifr range through 13z with winds light from the east. As winds switch around to the northwest cigs improve to vfr and continue through the rest of the period. Surface winds generally variable at speeds around 5kts or so. && .GLD Watches/Warnings/Advisories... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...BW AVIATION...99
Area Forecast Discussion National Weather Service Dodge City KS 125 AM CDT WED MAY 25 2016 ...Updated Aviation Section... .SHORT TERM...(This evening through Wednesday) Issued at 300 PM CDT Tue May 24 2016 Focus in the short term is severe weather tonight. Satellite shows cumulus across southwest Kansas. Sfc analysis shows an old outflow boundary moving north across the forecast district and a dryline farther to the southwest. We launched at 19Z special sounding. There is plenty of SBCAPE with values over 4000 J/kg. The sounding did show a significant cap in place, but this should erode over time with continued sfc heating. Wind shear is supportive for supercells with 38 kt of 0-6 km bulk shear and 21 kt of 0-1 km shear for tornadoes. The 12Z 4 km NAM showed intense supercells across southwest Kansas with significant updraft helicity. The HRRR is showing the same thing, although differs in location of the storms. Convection should form along the boundary across southwest Kansas (probably from Garden City down to Meade) and then move to the east through this evening. Threats will include tornadoes (some of which could be strong), giant hail of 3-4", and outflow winds as the system could form into a line later on in the evening. The central zones are most under the gun as far as severe weather is concerned. .LONG TERM...(Wednesday night through Tuesday) Issued at 300 PM CDT Tue May 24 2016 The next chance for storms in on Thursday as a wave moves out. Severe weather is possible once again during the afternoon and evening. The best chance of storms will be across the eastern zones. Beyond this we may see another chance of storms next weekend. Temperatures through the extended period will be on the warm to near normal side. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 123 AM CDT Wed May 25 2016 An outflow boundary from the large convective cluster in central and eastern Kansas extended from west central Kansas into northwest Oklahoma at 06Z, and widespread ceilings near 025 can be expected through at least 08Z. As the outflow erodes later tonight. flow above the boundary layer will become southwest in response to falling pressures in the northern plains, and the stratus should erode before sunrise. Southwest low level winds around 10 kts will prevail during the daylight hours, and dry air is likely to spread across all of southwest Kansas. A few cumulus clouds with bases near 060 should form in the afternoon, especially near HYS. Thunderstorms today should remain east of the TAF sites. Low level dry air will persist Wednesday night at TAF sites, although low level moisture will spread back west quickly on Thursday. VFR conditions are expected through at least Thursday afternoon. && .PRELIMINARY POINT TEMPS/POPS... DDC 61 89 57 87 / 70 0 0 20 GCK 58 90 52 87 / 40 0 0 20 EHA 53 90 52 86 / 0 0 0 10 LBL 56 91 54 89 / 20 0 0 10 HYS 56 87 57 85 / 70 0 0 50 P28 65 90 66 88 / 70 0 0 50 && .DDC Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Sugden LONG TERM...Sugden AVIATION...Ruthi