Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/30/24


Northern Alaska Forecast Discussion...CORRECTED
National Weather Service Fairbanks AK
1123 AM AKDT Sat Jun 29 2024 .SYNOPSIS... Warm weather will continue over much of the Interior through the weekend and into early next week. Areas of dense smoke from fires burning is reducing visibilities over the Middle Tanana Valley. Smoke will be in and out through the weekend. Dense smoke advisories expected to continue. Isolated storms will persist into the weekend. && .DISCUSSION... Analysis and Model Discussion... A strong vertically stacked low will remain in the central Bering Sea then drift across the Aleutians on Sunday as a 540 dam Low. Ridging will persist over the Interior this weekend. A trough will push across the eastern North slope late Sunday into Monday. Another low over Russia will push a front across Northwest Alaska on Tuesday. Ridging over the Interior will slowly break down Monday and Tuesday. Models in good agreement through the short term. The HRRR smoke model showing smoke persisting over the Interior through the weekend. Interior...Warm weather will continue over much of the Interior through the weekend. Highs in the mid 80s and a few upper 80s over the Yukon Flats. Areas of dense smoke from fires burning is reducing visibilities over the Middle Tanana Valley. Smoke will be in and out through the weekend. Air across Fairbanks and North Pole is very unhealthy this morning. Dense smoke advisories have been extended into Sunday. Smoke may thin and visibility may improve in the afternoon around Fairbanks but become dense again early morning on Sunday. High pressure builds back in for the weekend with rising temps back into the 80s, and much lower thunderstorm activity, with that ridge aloft suppressing thunderstorm potential. Isolated to widely scattered thunderstorms return over the southern Interior on Sunday. West Coast and Western Interior... High pressure in control over the majority of the west coast. Western Interior will remain warm over the weekend with highs in the upper 70s to low 80s. Showers continue to rotate around the Yukon Delta from the low in the southern Bering through the weekend. Widely scattered thunderstorms are possible from Grayling to Mcgrath on Sunday. Some of these storms will be fairly strong and may produce small hail and gusty winds with copious lightning. Monday is another warm day, with increasing southwesterly winds as a low approaches the NW Arctic. Possible change in the pattern by Tuesday with temps cooling and a front bringing rain showers to the west coast. Temps could drop to the 60s Tuesday into Wednesday. North Slope and Brooks Range... A little less thunderstorm activity today but still a chance for isolated thunderstorms over the eastern Brooks Range today from Anatuvak Pass to the AlCan border. On Sunday, isolated storms return over the southern Interior. A front will begin to impact northwest Alaska and the western Brooks Range with strong west-southwesterly winds. Extended Forecast Days 4-7... Long range models are coming more inline with a fairly large pattern shift beginning Tuesday, as a front from E Siberia moves inland across the NW Arctic and shifts east along the Brooks Range and eventually into the Interior through the remainder of the week. This will bring increasing west-southwest winds across the Mainland each day, with increasing chances for rainfall and cooler temps. Coastal Hazard Potential Days 3 and 4...None. && .FIRE WEATHER... Warm and relatively dry over the Interior through the weekend and into early Next week. Smoke and unhealthy air continues over the Middle Tanana Valley down to Delta Junction. Dense Smoke Advisories still in effect through Sunday. On Saturday, the thunderstorm threat moves Anatuvak Pass to the AlCan border. For now, widely scattered wet thunderstorms are expected. On Sunday, isolated to widely scattered thunderstorms return over the southern Interior and western Interior from Grayling to McGrath. Major pattern shift begins Tue and Wed as the upper ridge breaks down and a strong front moves into the NW Arctic and shifts east through the week, bringing potential wetting rains and much cooler temps, although strong southwest winds may create some critical fire weather conditions prior to that. Will continue to monitor. && .HYDROLOGY... Heavy rain showers and thunderstorms over the Brooks Range today may feed into faster moving streams and cause rapid rises, which will remain high into this weekend. Glacial fed rivers including the Tanana are beginning to rise as warming temperatures lead to increased high elevation snowmelt. && .AFG WATCHES/WARNINGS/ADVISORIES... AK...Dense Smoke Advisory for AKZ834-837-840-841-842-843-844-839. PK...None. && $$
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1038 PM EDT Sat Jun 29 2024 .SYNOPSIS... A moist southwest flow will bring periods of rain with a chance for thunderstorms into tonight. A cold front will bring additional scattered showers and thunderstorms Sunday, some of which could be strong to severe, mainly south and east of Albany. Fair weather with cool and breezy conditions return for Monday. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... .UPDATE...As of 1035 PM...According to the ALY 00z sounding, we officially broke today`s maximum daily PWAT value of 1.98" with a new value of 2.06"! Needless to say, we remain highly saturated throughout the area this evening. Despite this, showers continue to decrease in coverage with the main coverage in the Southwest Adirondacks. Higher reflectivity noted on the KENX radar indicates some heavier downpours embedded within these showers, but with rapid flow keeping them from remaining in one place for too long, accumulations have not been too impressive. In fact, the Old Forge Mesonet site only has about 0.34" for the latest 1-hour accumulation. Few updates were necessary with this update outside of minor updates to PoPs and temperatures to reflect latest obs and trends. The warm front now rests comfortably to the northeast with the surface trough approaching the region. Additional showers and possibly some embedded rumbles of thunder in the Southwest Adirondacks are possible throughout the night as the surface trough continues to push eastward. See the previous discussion for additional details. .PREVIOUS DISCUSSION... The area of rain that dominated much of the region this afternoon has decreased to mere scattered showers across the area this evening with the heaviest rainfall embedded within showers to the north and west of Albany. The latest SPC Mesoanalysis indicates increasing instability mainly to the west of the Hudson River with SBCAPE values at about 100-250 J/kg. This aligns well with the latest HRRR that depicts SBCAPE continuing to increase throughout the evening and into the overnight period especially in the Southwest Adirondacks. Speaking of the HRRR, this has been the model of choice for the evening as other sources of HiRes guidance have struggled to accurately resolve convection. According to the latest run, shower activity should continue to decrease such that coverage should become widely scattered over the coming hours. However, maintained thunder in the forecast especially after midnight for embedded rumbles of thunder as instability increases with almost stagnant low temperatures and sustained elevated dewpoints. Low temperatures overnight will primarily span the 60s with pockets near 70 mainly in the Mid-Hudson Valley and southwest New England. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... On Sunday, The Storm Prediction Center has placed the southeast part of our forecast area in a slight risk for severe weather with the rest of the area in a marginal risk. The cold front is forecast to move from northwest to southeast across the area. Ahead of the front the airmass will be unstable. We expect a band of showers/thunderstorms to develop and cross the region during the day Sunday. Heavy downpours and gusty winds could accompany some of these storms, as instability peaks in the afternoon with CAPES 1500-2000 J/kg and 0-6 km shear of 40-50 KT. Damaging wind gusts will be the primary severe threat, however can not rule a tornado or two across the Slight Risk area given the strong shear, potentially high instability and low LCL`s ahead of the cold front. High temps should reach the 80s for most valley areas and 70s across higher terrain areas. Heat indices will approach the mid 90s across portions of the mid Hudson Valley, but look to be below heat advisory thresholds. A few showers and storms may linger Sunday evening over the far southeastern areas and a few showers and storms may redevelop over the southern adirondacks in the evening with the upper level trough and cold pool moving southeastward. Monday looks cooler and breezy, but with the upper level trough overhead, a shower is possible over western New England. Otherwise clearing and cooler for Monday with highs mainly in the 70s. Mainly clear and cool for Monday night, with low temperatures in the 40s to lower 50s. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Surface high pressure will be centered over the region on Tuesday resulting in sunny, warm and dry weather. This high will push southeastward on Wednesday resulting in a southwest return flow of milder air. Wednesday should also remain mostly dry. Highs will rise well into the 80s across the valleys and the upper 70s to lower 80s in the higher elevations. A cold front associated with an area of low pressure tracking well northward into Quebec will slowly cross the region Wednesday night into Thursday, Independence Day. Showers and a few thunderstorms will likely accompany the front during this time. There remains a bit of uncertainty with the movement of the front. Best case scenario, the front moves through the area early thursday leaving a mostly fair Independence Day before the front returns northward Thursday night into Friday bringing additional showers and storms. Worse case the front stalls over the area with showers and storms on Independence day. Will monitor trends over the coming days. Otherwise, it looks to be a very warm and humid day on Thursday with heat index values reaching the 90s in the valley areas. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... Through 00z Monday...Flying conditions range from VFR (KALB/KPOU) to MVFR (KGFL/KPSF) across the terminals this evening due to low ceiling heights as low-level RH remains elevated ahead of a warm frontal passage. Today`s previous area of rain has been reduced to mere showers across the region this evening which are currently either just outside or within the vicinity of the TAF sites. Throughout the remainder of the evening, scattered showers are set to continue. Showers, especially those that contain heavier downpours and/or those that cross KGFL and KPSF whose ceilings are on the lower end of MVFR thresholds, will be capable of dropping VFR/MVFR ceilings to MVFR/IFR heights. At this time, impacts to visibility are not anticipated, though will monitor conditions and make amendments should a heavier downpour look to potentially cause reductions. While the latest HiRes models indicate a fair reduction in coverage to showers for the overnight period, the latest HRRR indicates some light showers could cross each of the terminals during the overnight period. These are not expected to reduce visibility past VFR thresholds, but once again MVFR to IFR ceilings are possible especially at KGFL and KPSF. This looks to be most likely between 06-09z and TEMPOs were added to the TAFs accordingly. Shower activity should break at the terminals by daybreak, yielding VFR to MVFR ceilings across the terminals. Tomorrow, a period of showers and thunderstorms will be possible ahead of a passing cold front. Included PROB30 groups to reflect this likelihood, though uncertainty still exists pertaining to the exact timing due to model disagreement. Will provide adjustments in future updates. Winds throughout the period will remain breezy out of the south to southwest. Sustained speeds ranging from 10-15 kt with gusts of 15-27 kt will remain possible through the evening before decreases to sustained speeds of 6-10 kt occurr for the overnight. Tomorrow, sustained speeds will range form 5-10 kt. Outlook... Sunday Night: Low Operational Impact. Breezy. NO SIG WX. Monday: Low Operational Impact. Breezy. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: Low Operational Impact. Breezy. NO SIG WX. Wednesday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Independence Day: Low Operational Impact. Slight Chance of SHRA...TSRA. && .HYDROLOGY... There is a marginal risk for excessive rainfall today and tonight across all but Litchfield County CT. Showers will continue to overspread the region tonight, with embedded thunderstorms developing later today into tonight. High PWAT`s of ~2", warm cloud depth and some potential training of thunderstorms could lead to heavy rainfall and localized flooding tonight into Sunday. The greatest potential for this looks to be across the southern Adirondacks and western Mohawk Valley for tonight, where some areas have already received over an inch of rain. Localized flooding of urban, low lying and poor drainage areas is possible from any thunderstorms. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...SND NEAR TERM...Gant SHORT TERM...SND LONG TERM...SND AVIATION...Gant HYDROLOGY...SND/KL
Area Forecast Discussion
National Weather Service Boston/Norton MA
748 PM EDT Sat Jun 29 2024 .SYNOPSIS... A slow-moving frontal system brings two rounds of scattered showers and thunderstorms, tonight into early Sunday morning, and then perhaps again Sunday afternoon and evening. Passing widely scattered afternoon showers are possible on Monday, although drier weather prevails most of the time. High pressure brings dry weather, seasonably warm temperatures and low levels of humidity for Tuesday and Wednesday. While the timing is still uncertain, turning more humid and unsettled for the Fourth of July thru the early part of the weekend with a couple of disturbances offering chances for clouds, showers and thunderstorms. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... 735 PM Update: Radar imagery at this hour reflects what is amounting to very light showers largely north and west of I-95, gradually moving eastward. However METARs and mesonet information indicate little if any QPF at all with this, with only a handful or so of sites actually recording measurable precip. Did boost PoP up into the Likely/low Categorical range at least thru midnight for most areas, but at least through midnight, this is the textbook "high-PoP/low-QPF" scenario that you`ll ever find. So while radar looks imposing, there really isn`t much rain falling from these echoes. Also backed off on the thunder mention for this period of time. However we think that changes for the 2nd half of the evening into early Sun AM, but mainly for CT-central/southern RI-SE MA. Watching a cluster of t-storms with cooling cloud tops over eastern PA NW of the Philly area with additional re- development over north-central PA, with both areas moving ENE in the WSW flow aloft. For Southern New England, most models show rising dewpoints into the lower 70s later in the overnight into the pre-dawn hrs. With higher dewpoints at night, LCL heights are lower and with that comes somewhat higher most-unstable CAPE values (around 500-900 J/kg or so) mainly from HFD-IJD-PVD-PYM southward. Convective-permitting guidance varies on the handling of this, with the past several HRRR runs being the most bullish in the outlined area, with more tepid/muted answers from the WRF suite and the 18z NAM-3km. So for the 2nd half of the overnight into early Sunday, ended up reducing PoP elsewhere to around a chance level (25-30%) but boosted PoP to categorical for the southern third, added mention of thunder and increased QPF during the 06-12z Sunday period. Not expecting severe with this but if current/new development sustains itself in this setting, we could see overnight lightning and heavy downpours roughly from Hartford to Providence to Cape Cod. The rising dewpoints should also lead to more expansive stratus development for the coastal areas, but pretty strong southerly winds should keep fog to a minimum. No changes to lows which look on track attm. Previous discussion: Showers assocd with a weak mid level shortwave and anomalous PWAT axis are moving into northern and western MA this afternoon. Expect a period of showers across all SNE through the evening and into the overnight as deep moisture axis with 2-2.25" PWATs move into the region. Marginal elevated instability develops so can`t rule out an isolated t-storm, but the best chance may come toward daybreak along the south coast and Cape/Islands. A few of the CAMs are showing this potential but there is uncertainty regarding whether the convection stays offshore or extends further north along the south coast. Something that needs to monitored overnight as high PWAT airmass supports heavy rainfall. Otherwise, it will be a somewhat breezy night as modest low level jet develops. The SW flow will bring increasing humidity as dewpoints climb to around 70 overnight. Temps will be nearly steady in the upper 60s to lower 70s. Stratus and patchy fog will develop. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... Sunday and Sunday night... * A round of strong to severe t-storms possible Sun afternoon and evening * Damaging wind gusts are the primary threat but large hail, heavy rainfall and also a tornado is possible An area of showers and a few t-storms may be ongoing along the south coast and Cape/Islands to start the day. There is lower than normal confidence as convection could end up further south but if it does extend along the south coast, it will move offshore by late morning. Otherwise, stratus and patchy fog will burn off away from the south coast leading to partial sunshine. Given warm sector airmass with 925 mb temps 22-24C, temps should reach well into the 80s to near 90 away in the interior. Stratus will likely linger into the afternoon along the south coast with temps holding in the upper 70s with SW flow. Oppressive humidity is likely with dewpoints reaching the low to mid 70s. Heat indices expected to approach 95 in the CT and Merrimack valleys. The main forecast concern will be the potential for strong to severe t-storms in the afternoon and evening as a strong cold approaches from the west. The increasing forcing for ascent will likely result in a greater areal coverage of storms. Mid level lapse rates are marginal, but the heat and high dewpoints should make up for this with CAPES likely reaching 1500-2500 J/kg in the interior. This instability combined with impressive deep layer shear of 40-50 kt is very favorable for organized storms. Given strong linear forcing ahead of the front, storms will likely organize into line segments or even some sort of QLCS as indicated by all the hi-res CAMs. Damaging wind gusts will be the primary threat, but can`t rule out large hail or even a tornado if any discrete supercells can develop. SPC SREF showing moderate probs of STP > 1. Best chance of severe weather will likely be north and west of I-95 due to marine layer near the coast and CSU machine learning probs and HREF updraft helicity are highlighting the interior for severe weather. Also can`t rule out locally heavy rainfall and flooding from t-storms but severe weather appears to be the greater threat. Storms are expected after 2 pm across interior northern and western MA, gradually reaching the south coast Sun evening. Convection should be in a weakened state by the time it reaches the coast due to weaker instability but strong shear may help to sustain convection a bit longer. Showers and a few storms could linger into the overnight period over the Cape/Islands, otherwise decent drying will be moving into the region overnight as cold front gradually pushes offshore with NW flow developing. && .LONG TERM /MONDAY THROUGH SATURDAY/... Highlights: * Hit-or-miss widely scattered showers Mon, but most stay dry with lowering humidity levels. * Dry and warm but with tolerable humidity levels for Tue and Wed. * Turning more humid and more active for the Fourth of July, and potentially into Fri/Sat too, with clouds, showers and storms possible. Exact timing still uncertain. Details: Monday: Surface ridge associated with a seasonably-strong 1024 mb high pressure over the Gt Lakes region eventually builds in. Will still see generally improving conditions, although shortwave disturbance aloft and associated cooler pool of air aloft should produce enough if still meager instability to pop diurnal cumulus clouds and hit-or- miss showers in widely scattered coverage. Can`t really rule out a shower anywhere in Southern New England, although central MA eastward has somewhat better chances with somewhat higher surface dewpoints (lower 60s). However not expecting washouts with these showers. Conditions improve significantly toward drier weather by the evening both with waning diurnal instability and passage of the shortwave disturbance aloft, with falling dewpoints into the 50s thru evening on northerly winds. Highs in the mid/upper 70s and lows in the mid/upper 50s. Tuesday and Wednesday: 500 mb heights briefly rise in this period, along with high pressure settles in over the Northeast in this period. This high shifts offshore later into Wed night. Leads to a couple of tranquil and pleasant early-July days with comfortable humidity levels and highs in the low to mid 80s. As high pressure moves offshore late Wed evening, SW flow and weakening 500 mb heights (upper ridge shifting east) should bring increased cloud cover and rising dewpoints/humidity levels. Flow aloft also strengthens a bit; ahead of a frontal system for the Fourth of July, that preceding stronger flow aloft could bring a canopy of cloud cover in potentially quicker than current forecast calls for on Wed evening. Thus lows also warmer in the mid to upper 60s. Fourth of July Holiday: While primary weak-amplitude disturbance aloft in fast westerly flow passes to the north into Quebec/northern New England, the Fourth of July is looking active as a sagging cold front moves southeast through New England. This front should act on an increasingly humid air mass to favor showers and t-storms. Greatest uncertainties at this time lie in the timing and how warm/degree of instability, and kept PoPs pretty broadly in the Chance range for now and then re- assess once there is better clarity on each of those. But as it looks now it does look like Thurs and potentially into Thurs night features clouds and showers/storms. With dewpoints in the upper 60s to mid 70s, it should also be quite humid. Kept highs in the mid 80s for now as well, although clouds and shower/storm coverage will dictate adjustments to highs as well. Lows in the mid to upper 60s. Friday and Saturday: Forecast for Fri is uncertain as there looks to be another disturbance aloft which tries to send a warm front back into Southern New England either Fri or Fri evening/Sat. GFS is the quickest in progressing this feature into our area into Fri, while the ECMWF/Canadian GEM and its ensembles are slower, more into Sat. Kept PoP pretty broadly into the Chance range here given the uncertainties which are close to NBM values; these too will also need to be adjusted pending trends in subsequent guidance. && .AVIATION /23Z SATURDAY THROUGH THURSDAY/... Forecast Confidence Levels: Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 00z TAF Update: Tonight: Moderate confidence. Conditions gradually deteriorate from VFR to VFR/MVFR levels through midnight for most, with more degraded/MVFR-IFR more likely for the southern TAFs. Current area of -SHRA are light and not restricting visby and expect that to continue. The exception is after 06z with the risk for +SHRA/TSRA from HFD- IJD-PVD-PYM southward into the Cape and Islands. Risk for lightning and localized downpours for these areas. Can`t rule out a shower north of these areas but not expecting much north of this line. SSW winds around 10-15 kt with gusts 20-25 kt. Sunday...Moderate confidence. Conditions improve to VFR interior by 16z. However, IFR may linger through the afternoon along the south coast. SW gusts to 20-25 kt. Showers and possibly a few t-storms should be exiting the Cape/Islands in the morning. Then another round of showers/t-storms expected to develop after 18z in the interior, reaching the south coast in the evening. A few strong to severe storms possible with damaging wind gusts the primary threat. Sunday night...Moderate confidence. IFR with showers/t-storms in the evening along the south coast, then improving to VFR overnight. Wind shift to NW 00-06z. KBOS TAF...Moderate confidence in TAF. Generally OVC VFR with P6SM -SHRA, with deterioration to at least MVFR ceilings overnight. Improving to VFR around 16z Sun with another round of showers/t-storms after 20z. SSW winds around 10-15 kt with gusts 20-24 kt. KBDL TAF...Moderate confidence in TAF. MVFR cigs lowering to IFR this evening as light showers move across the region. Low risk for embedded thunder after 06z. Improving to VFR by 15z Sun with another round of showers/t-storms after 20z. Outlook /Monday through Thursday/... Monday: VFR. Breezy. Slight chance SHRA. Monday Night through Tuesday Night: VFR. Wednesday: VFR. Breezy. Wednesday Night: VFR. Breezy. Chance SHRA. Independence Day: Mainly VFR, with local MVFR possible. Breezy. Slight chance SHRA, slight chance TSRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Through Sunday night...High confidence. Gusty S winds tonight becoming SW on Sunday with gusts to 25 kt at times. SCA continued for all waters. Winds shift to NW overnight Sun night behind the cold front. Vsbys reduced in developing showers and fog tonight, with fog lingering on Sunday especially south coastal waters. A few t-storms possible over southern waters late tonight and Sun morning, then more showers and t-storms moving across the waters late Sun and Sun night. Outlook /Monday through Thursday/... Monday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers. Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Tuesday through Wednesday: Winds less than 25 kt. Wednesday Night: Winds less than 25 kt. Slight chance of rain showers. Independence Day: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers, isolated thunderstorms. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 10 AM EDT Sunday for ANZ230-236-251. Small Craft Advisory until 8 PM EDT Sunday for ANZ231-250. Small Craft Advisory until 11 PM EDT Sunday for ANZ232>235-237. Small Craft Advisory until 6 AM EDT Monday for ANZ254>256. && $$ SYNOPSIS...KJC/Loconto NEAR TERM...KJC/Loconto SHORT TERM...KJC LONG TERM...Loconto AVIATION...KJC/Loconto MARINE...KJC/Loconto
Area Forecast Discussion
National Weather Service State College PA
1158 PM EDT Sat Jun 29 2024 .SYNOPSIS... A cold front will push through central Pennsylvania on Sunday. A large high pressure system will build into the region early in the upcoming week, followed by a dying cold front pushing in from the Great Lakes and stalling out over the area late next week by the middle of next week. && .NEAR TERM /THROUGH SUNDAY/... Lingering convection over parts of the south central and southeast late this evening should continue to decrease in coverage after midnight. Can`t drop POPs altogether overnight as 850 mb thermal ridge is overhead and additional isolated showers can still pop up overnight, but most areas will remain dry. We expect there to be areas of fog give current dewpoint depressions of 1-3F and dewpoints in the lower 70s. Some areas of fog are very likely given high surface dewpoints and light winds ahead of the cold front that will be approaching from the GLAKS and Ohio Valley overnight. With thermal trough in place and 850 temps around +18 to +19 across much of central PA, lows tonight will be warm, ranging from the mid 60s to mid 70s, which is 10 to 15 deg F above normal for late June. && .SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/... Passage upstream surface cold front will bring the chance for another round of convection Sunday. Locations most likely to see potential strong/svr t-storms are over the southeastern part of the CWA due to a fropa coinciding with peak heating of the late afternoon. Max temps Sunday will be a few to several deg F higher than today (Sat) in all locations. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... Dewpoints drop off rapidly by Sunday evening with another comfortable few days of weather in store to start the month of July. Canadian high pressure builds to southern Ontario by Monday night, bringing a fair and cool night with the high moving directly overhead. This will result in efficient radiational cooling and min temps several degrees below normal. Fair and warmer weather is expected Tuesday into at least the first half of Wednesday, as upper level ridging builds over the state and surface high drifts offshore. All medium range guidance tracks a weakening shortwave well north of PA late Wednesday into Thursday. The dying cold front is likely to sag into the state Thursday and stall out in the vicinity of PA through Friday. Falling heights/surging low level moisture ahead of the front could support scattered convection as early as Wednesday afternoon over the northwest half of PA. However, a better chance of showers/tsra areawide will come with the arrival of the front Thu into Friday. Early best guess of late week rainfall based on ensemble plumes ranges from 0.25 to 0.75 inches, with the highest amounts over the N Mtns and least in the south. Heat and humidity should peak ahead of the front Wed-Thu. Ensemble mean 850mb temps surging to near 20C indicate max temps could reach the low to perhaps mid 90s in the Lower Susq Valley Thursday, with high humidity pushing heat indices into the mid and upper 90s. Ensemble plumes suggest slightly cooler daytime temps late week, due to more clouds/showers. However, high pwats in the vicinity of the stalling front should result in muggy nights and above normal min temps the entire second half of next week. Models begin to diverge as we head into the weekend. Most guidance suggests that rain chances stick around through at least Saturday as another cold front approaches the area. && .AVIATION /04Z SUNDAY THROUGH THURSDAY/... A few more adjustments made just before I sent the 00 TAF package. Main thing was to add in some VCSH early on, as the airmass is supporting a few showers forming since about an hour ago. Earlier discussion below. Adjusted TAFS several times this afternoon and early this evening, as line of storms that formed over the mountains earlier this afternoon have been moving along at a rather fast pace. Still concern that the far southeast activity may slow some, given the southeast flow and very high dewpoints in place now. Main change to the 00Z TAF package was to back off on showers overnight, and put showers in toward Sunday morning, given location of main cold front and upper level forcing. Still expect conditions to improve later Sunday, as the winds shift to the northwest and much less humid air moves into the area from northwest to southeast. Monday and Tuesday look dry at this point with a dry airmass and VFR conditions, as high pressure builds into the area. A bit breezy on Monday, given the cooler air being advected into the region. Outlook... Mon-Tue...Dry weather with VFR conditions except perhaps some AM valley fog N. Wed...PM TSRA moving across from W-E. Thu...A chance of showers and storms. && .HYDROLOGY... Over half of an inch of rain last night and this morning over the far NW has increased confidence that the precip in the N will be very efficient today. While dbZ and the amt of ltg may not impress today, the moist adibatic profiles and deep warm layer will make for heavy rain at times. Draw back to fast storm motions: 1) radar may underestimate precip as the fast cells skip along in between scans, and 2) it`s tough to get flooding when the cells have a low residence time. However the repeated showers/storms could (easily) overcome that issue. Prev... The area of greatest concern for heavy rain and flash flooding will spread south and east later this morning through this afternoon as the axis of the LLJ slides east and the favorable RR quad of an approx 2 sigma upper level jet and its enhanced MESO-B lift moves overhead. PWAT values increased steadily from west to east overnight from a little over one inch to start the night to around 1.6 inches early today. PWATS via the GEFS will peak around +3 sigma or about 2.25 inches later this morning through this afternoon (which are values that haven`t been seen so far in PA during 2024). This anomalous, deep moisture will support the threat for locally very heavy rain (in excess of 2 inches/hour) within a broad area of 1 to 1.5 inch basin average storm total rain forecast for much of Central and Northern PA. Issued a Flood Watch from 12Z today through 06Z Sunday for much of Central and Northern PA where FFG values are well under 2 inches/3 hours across parts of the Northern Mtns. && .CLIMATE... At the Altoona Airport, a record rainfall of 0.76 inches was set today. This total breaks the old record of 0.53 inches set back in 1972. Through 6/27,June ranks as the second warmest on record at Harrisburg with an average monthly temperature of 76 degrees or +3.8 degrees above normal. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Lambert/DeVoir/Fitzgerald NEAR TERM...Lambert/DeVoir/Fitzgerald/Dangelo/Martin SHORT TERM...DeVoir/Fitzgerald/Steinbugl LONG TERM...DeVoir/Fitzgerald/Bauco AVIATION...Martin HYDROLOGY...Lambert/Dangelo CLIMATE...Evans/Steinbugl
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
608 PM MDT Sat Jun 29 2024 ...New AVIATION... .SYNOPSIS... Issued at 200 PM MDT Sat Jun 29 2024 Daily thunderstorm chances will continue throughout the entire period with Wednesday showing the highest probability for showers and thunderstorms. Temperatures will run near or a few degrees above normal. && .DISCUSSION... Issued at 200 PM MDT Sat Jun 29 2024 The monsoonal pattern is well established with the presence of the summertime subtropical ridge. The location of this ridge will be what drives our weather for the period, and really the remainder of the summer. Starting off, it`s centered over the DFW area, but with a ridge axis extending well to its west (and east), reaching into our CWA. This pattern has worked to bring warm temperatures aloft along with some subsidence as well as import drier air. PWats were around 1.2" on this morning`s EPZ sounding. Satellite and radar are relatively quiet as of 1PM with just a few showers over the Gila and Sacs as thermodynamics and dynamics are presently limited thanks to the high. With that said, however, an easterly push is expected to arrive this afternoon, moving east to west, which will likely aid in thunderstorm development by adding some low-level lift though isolated to maybe scattered coverage is expected. Air mass wise, moisture and temperature (or in terms of theta-e) advection will be fairly neutral, at least initially. Temperatures for Sunday will be around 5 degrees cooler in spite of the ridge continuing to nudge westward. The HRRR is showing an uptick for thunderstorm coverage for tomorrow in spite of the cooler temperatures. An easterly wave over Mexico was over Southern Chihuahua as of typing this discussion with a trailing vort max arcing toward the Rio Grande Valley of TX. The bulk of this easterly wave looks to continue into the Pacific according to the GFS, but the GFS and NAM show the trailing vort tube and moisture forced northward into the CWA, which if true, would provide subtle DPVA. As we head into Monday, the ridge will begin making a slow trek to the east while ridging strengthens off the Pacific Coast. For Monday and Tuesday, temperatures will climb some as today`s air mass retreats east while thunderstorm chances follow their usual preference toward the mountains with at least isolated coverage spreading into the lowlands. On Wednesday, the ridge moves far enough east, a weakness/trough develops over NM between the Pacific Ridge and subtropical ridge over the CONUS. Moisture will center within this weakness, giving our entire CWA its best chance for precipitation of the period. GFS shows PW values over 1.5" while the ECMWF shows dew points in the mid 50s. Heavy rain and flash flooding would be the main concern. Drier air will try and push in from the northwest beginning Thursday with models disagreeing on how far south it will go. The other important thing about NW-flow is it opens the door for disturbances to directly impact our CWA either via frontal pushes, which is hinted at for next Saturday or DPVA, which usually stems from features too subtle for models to pick-up this far in advance. All that said, thunderstorm chances will continue as we finish out the work week while temperatures hover near or just above average. Looking at NBM temperatures for KELP, the spread between the 25th and 75th percentile is as much as ten degrees by next weekend, indicating the uncertainty of how much cooler air NW flow will allow to push into Southern NM and Far W Texas. && .AVIATION... (00Z TAFS) Issued at 557 PM MDT Sat Jun 29 2024 Thunderstorms are moving from the east to the west across the region. The threat for thunderstorms at KELP has ended and will end shortly for KLRU, but the threat for thunderstorms and strong thunderstorm winds will continue for the next few hours for KDMN and KTCS. Later the winds will slow and our ceilings will become unlimited by 10 PM. Winds will generally be light from the east tonight, but the low end east or southeast winds gusty winds will return on Sunday. Like today there will be another threat for afternoon and evening thunderstorms across the area, but the confidence right now of it impacting a certain airport is not high, so I have not mentioned the threat is the round of TAF`s. && .FIRE WEATHER... Issued at 200 PM MDT Sat Jun 29 2024 Minimal fire concerns continue as we remain in a monsoonal pattern. Temperatures are not expected to be as hot for Sunday, which will allow for higher min RH values in the afternoon, only falling into the mid 20s. Winds will remain light. Thunderstorm development is expected again tomorrow afternoon with the HRRR showing an increase in coverage than seen the past two days. Regardless, convection will be favored in the mountains. The main concern with any storm will be gusty winds. Thunderstorm coverage and chances will decrease some for Monday and Tuesday before increasing again Wednesday. Venting will range very good to excellent for Sunday and good to very good for Monday. && .PRELIMINARY POINT TEMPS/POPS... El Paso 82 102 81 101 / 30 30 50 10 Sierra Blanca 71 94 69 94 / 20 30 20 10 Las Cruces 76 99 74 99 / 60 30 60 20 Alamogordo 69 96 70 96 / 30 20 30 10 Cloudcroft 52 73 53 72 / 30 30 30 30 Truth or Consequences 75 95 73 94 / 60 20 60 40 Silver City 68 90 66 88 / 70 40 80 60 Deming 75 98 72 96 / 70 30 80 30 Lordsburg 73 97 71 94 / 70 40 90 50 West El Paso Metro 79 99 78 98 / 40 30 50 10 Dell City 73 98 72 98 / 10 20 20 10 Fort Hancock 77 101 74 101 / 20 30 30 10 Loma Linda 71 93 70 91 / 20 30 40 10 Fabens 79 100 76 100 / 20 30 40 10 Santa Teresa 77 97 74 96 / 40 30 60 20 White Sands HQ 77 96 76 96 / 40 20 50 20 Jornada Range 73 96 71 95 / 50 20 60 20 Hatch 73 98 71 97 / 60 20 60 30 Columbus 76 97 73 96 / 70 30 80 20 Orogrande 75 96 73 96 / 30 20 40 10 Mayhill 57 84 58 84 / 30 40 20 30 Mescalero 57 85 58 83 / 30 30 30 30 Timberon 56 82 55 82 / 20 30 30 20 Winston 63 86 61 84 / 60 30 70 70 Hillsboro 70 92 68 91 / 70 30 70 60 Spaceport 70 95 68 94 / 60 20 60 30 Lake Roberts 63 90 62 86 / 60 40 80 70 Hurley 69 93 66 91 / 70 30 80 50 Cliff 68 99 66 96 / 60 30 80 60 Mule Creek 69 93 67 89 / 60 40 80 70 Faywood 70 91 68 89 / 70 30 80 50 Animas 70 97 69 94 / 70 50 80 50 Hachita 70 96 69 95 / 80 40 80 40 Antelope Wells 69 95 68 94 / 80 70 90 50 Cloverdale 65 90 66 89 / 80 70 80 50 && .EPZ WATCHES/WARNINGS/ADVISORIES... TX...Heat Advisory until 6 AM MDT Sunday for TXZ418-419-423-424. NM...Heat Advisory until 6 AM MDT Sunday for NMZ407-410-411-427>429. Flood Watch until midnight MDT tonight for NMZ415-416. && $$ FORECASTER...15-Brice
Area Forecast Discussion
National Weather Service Goodland KS
946 PM MDT Sat Jun 29 2024 .KEY MESSAGES... - Low confidence with regard to thunderstorm development tonight and Sunday night. - Much cooler highs Sunday due to cloud cover all day. - Hot weather returns Monday behind a warm front. However highs are not as hot. - Chances for storms each day, mainly during the evening. && .SHORT TERM /THROUGH SUNDAY NIGHT/... Issued at 216 PM MDT Sat Jun 29 2024 Latest upper air analysis shows nearly zonal flow over the central Plains. Pockets of higher water vapor were moving through this flow, leading to cloud cover. At the surface winds were breezy from the northeast. A surface high pressure was located over Wyoming. For the rest of the afternoon the surface high pressure will slide southeast across Nebraska, causing the winds to turn to the southeast. As the high pressure approaches winds will decline. This evening a weaker upper level short wave trough will move over the forecast area from the west. The latest model runs have slightly delayed the arrival of the upper level short wave trough. (This is in line with the delayed trend in storm arrival of the last few days.) Models are now keeping the cold front well south of the forecast area during the night. However the low level jet will strength over the front and into the forecast area. This will provide low level moisture advection ahead of the approaching upper level short wave trough. Both the NAM and RAP models are suggesting elevated instability will be present with in this part of the forecast area. In addition there does look to be a weak LLJ nose over the southern part of the forecast area. Am thinking scattered storms should form ahead of the approaching upper level short wave trough around midnight, then gradually spread east-northeast ahead of the short wave trough. Storms will be moving around 15 MPH, which may lead to heavy rainfall given the precipitable water values of over an inch in that part of the forecast area. The storm activity may last well into Sunday morning. At this time confidence for severe weather occurring over the southern part of the forecast area is low (30%). This is due to the midlevel lapse rates being around 6C/km and deep layer shear being 25-30kts. Strong thunderstorms seem more likely in this environment. If severe thunderstorms were to form, quarter size hail would be the main threat. The highest elevated instability will be around midnight. This threat area may shift north or south, however the latest model run has shifted the elevated instability south. Meanwhile the continued moisture advection from the LLJ will bring in low clouds from the south. These will start from the CO/KS border then gradually expand eastward through the overnight hours. The surface high over Nebraska will also aid in advecting moisture over the forecast area. Sunday morning the upper level short wave trough will continue to move across the southeast part of the forecast area. Elevated instability will continue to decline. Storm activity should be east of Graham County by noon, if not before. Sunday afternoon an upper level short wave ridge will move in from the west. By this time the surface high pressure will be Central Nebraska into Central Kansas. Moisture advection will continue. Soundings show atleast a broken, if not overcast cloud deck over the forecast area through the day. The exception will be East Central CO where the moisture advection will be less, allowing the clouds to break up during the afternoon. Lowered highs a few more degrees for the afternoon, mainly east of CO. The 25th percentile high temperature forecast is in the low/mid 70s for this part of the forecast area. Based on this the current forecast seems representative. Sunday night another upper level short wave trough will move in from the west. By this time the ridge has shifted more to the west, pushing the upper level flow slightly more to the north. During the evening there may be some low level convergence from the LLJ over the northwest part of the forecast area as the short wave trough moves through. This convergence then shifts to the northern part of the forecast area, moving with the upper level short wave trough. Models show deep layer shear of 40 kts and midlevel lapse rates around 7C/km. The current data supports the potential for storms to become severe given the elevated instability could occur. However, the elevated instability is highly dependent on how warm will 800- 700mb layer be and how high will the dew points be in that layer. The HREF has not strong storms in the forecast area at this point. For now this bears watching as strong to severe elevated thunderstorms could occur. However confidence is low (20%) for them to occur given how much could change with the small details regarding the low level temperature and moisture advection. && .LONG TERM /MONDAY THROUGH SATURDAY/... Issued at 216 PM MDT Sat Jun 29 2024 Monday the front will move back through as a warm front. Models have shifted the upper level ridge slightly more to the east. This move has also shifted where the dome of hottest temperatures will be, resulting in highs not being as hot for the forecast area. Heat index values are now around 100F instead of 105F. During the latter part of the afternoon a stronger upper level short wave trough will move into the forecast area from the west. Midlevel lapse rates sharply decline behind the trough, suggesting there maybe a narrow window for strong to severe thunderstorms to form. Monday night the storm activity will move east across the forecast area. A band of frontogenesis accompanies the trough across the forecast area, mainly over the northern half of the forecast area. As such, have the best chances for rainfall there. Tuesday through Saturday evening chances for rainfall each day are forecast as upper level short wave troughs move over the forecast area. The upper level ridge will shift west and become centered over the Desert Southwest. This will shift the storm track to be from the northwest over the forecast area. Rainfall chances during this timeframe seem high, which may be due to the monsoonal moisture moving over the forecast area. Wouldn`t be surprised if the rainfall chances end up lowering as we move through the week. Due to the ridge ridge shifting west of the forecast area, highs will not be as hot. The coolest temperatures are Friday when a stronger upper level short wave trough rounds the ridge and brings a cold front with it. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 945 PM MDT Sat Jun 29 2024 GLD: VFR conditions will prevail this evening/overnight. MVFR ceilings are anticipated to rapidly develop around or shortly after sunrise (~12-14Z). Deterioration to IFR is expected thereafter, during the mid-late morning. While some improvement to MVFR is expected during the afternoon, ceilings will likely deteriorate to IFR-LIFR around or shortly after sunset Sunday evening, near the end of the TAF period. Easterly winds at 7-13 knots (this evening) will gradually veer to the SE (overnight) and SSE (Sunday morning).. increasing to 15-25 knots during the day. MCK: VFR conditions will prevail this evening/overnight.. and through much (or all) of Sunday morning. Borderline VFR-MVFR ceilings (~2500-3500 ft AGL) are anticipated to develop by early afternoon (~16-19Z) and persist throughout the day. Ceilings will likely deteriorate to low-end MVFR or IFR a few hours after sunset Sunday evening, near the end of the TAF period. Easterly winds at 6-12 knots (this evening) will gradually veer to the SE (overnight) and SSE (Sunday afternoon).. increasing to 15-20 knots by mid-late afternoon. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...Trigg LONG TERM...KMK AVIATION...Vincent
Area Forecast Discussion
National Weather Service Gray ME
742 PM EDT Sat Jun 29 2024 .SYNOPSIS... A warm front will bring a period of rain with a few embedded thunderstorms to the region tonight before a potent cold front arrives Sunday afternoon bringing the potential for strong to severe thunderstorms. High pressure arrives early next week with dry weather and seasonable temperatures expected for the first half of next week. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... 730 PM Update...Little change to the going forecast for the evening as as back edge to steadiest rainfall moving out. However, convective showers and islolated thunderstormns currently over Upstate NY will likely move ino western zones in a few hours. Otherwise, cloudy and breezy. High Impact Weather Potential: A few downpours are possible overnight as well as an isolated thunderstorm though the threat for widespread flooding and severe weather is low. Pattern: Early afternoon water vapor imagery shows a potent shortwave dropping through the western Great Lakes with a plume of mid level moisture pushing into the northeastern United States. Beneath this plume...a warm front is slowly advancing through NY/PA with a broad region of light to moderate rain fueled by increasing moisture and a 50kt southwesterly LLJ. Forecast concerns for tonight center on rainfall potential as the surface warm front lifts through the region. Through this evening: Rain is overspreading the region from west to east and this will continue through the evening hours with clouds lowering. SE NH may escape meaningful rainfall through 8pm...but elsewhere conditions will turn wet. Temperatures won/t really move much...largely sitting in the 60s across the area. Tonight: Warm front lifts north and east through the region tonight with 2" PWAT plume overhead this evening gradually shifting east of the area by daybreak Sunday. While isentropic ascent up the frontal surface in the presence of some weak elevated instability will be sufficient to support rainfall...broader scale forcing appears rather lackluster through the overnight with +DPVA mostly brushing the international boarder with some weak height falls overhead and some jet entrance support. Overall this suggests occasional showers through the overnight...with the greatest threat for a few downpours being over the mountains where the synoptic scale forcing is best. From a hazard perspective...the threat for flooding appears rather low...but nonzero given the deep moisture/warm cloud depths. A mild night is in store given continued warm air advection with lows falling into the mid 50s in the mountains with 60s to the south. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... High Impact Weather Potential: * Slight Risk of Severe Thunderstorms * Primary threat: Damaging Wind * Secondary threats: Localized flooding...hail and an isolated tornado * Timing: 12pm-7pm Pattern: Low pressure north of northern New England will move north and east during the day with a cold front over western New York as a positively-tilted shortwave and region of mid level height falls pushes just north of the region through the day. Our forecast focus will be on severe convective potential as the surface cold front crosses the area Sunday afternoon. Also watching heat indices across southern NH which may make a run at advisory thresholds ahead of the front. Sunday: Shortwave rotating through the positively-tilted longwave trough races just north of the region through the day with 70kt H5 speed max moving overhead in tandem with right entrance region to 120kt upper level jet. Should see some sun in the morning as we move into the warm sector ahead of the cold front but convection may already be ongoing across western New York...strengthening as downstream instability strengthens. By early afternoon convection will likely reach the mountains of NH as well as the CT Valley with the mesoscale guidance favoring the potential for one line of storms closer to the beset mid level forcing moving from northern NH ESE through the Capitol region of ME with another line moving across southern NH where the best instability will be located and will be downstream of the most likely location for morning convection. Here/s a run through the convective parameters.... Instability: Sizable disparity in the guidance here with the NAM nest and the HRRR in their typical wetter/drier camps...respectively. Looking at upstream llevel moisture...a compromise is likely best which favors 1500 J/kg of MLCAPE in southeast of the mountains as surface dewpoints push just above 70. Shear: 40kts in the 0-3km layer with 60kts in the 0-6km layer. Hodographs are fairly straight and parallel to the approaching frontal boundary. Expect initial cells to grow into lines with bowing segments likely given ample 0-3km shear. Within these bows would be the best potential for a spin up. Lapse rates: Decent in the H8-7 layer, but weaker /around 6C/ in the H7-5 layer. Sufficient to support deep convection through the afternoon. Overall...this lines up well with the SPC outlook for damaging winds posing our greatest severe weather risk with hail and an isolated tornado lesser...but non-zero threats. T8s pushing to +18C should allow highs to reach near the 90F mark given sufficient sun. This...in addition to dewpoints moving above 70 will allow a few spots in southern NH/SW ME to approach heat advisory levels...but not high enough or long enough to warrant any headline issuance today. Sunday Night: With the surface cold front near the coast to begin the period...expect any convection to quickly be exiting the region with mesoscale guidance suggesting a few showers along a secondary trough/cold front that crosses the region overnight. Best potential for these overnight will be in the mountains with at least partial clearing elsewhere. Cold air advection will push T8s back into the upper single digits by daybreak Monday with lows to fall into the 50s in the mountains and lower 60s elsewhere. && .LONG TERM /MONDAY THROUGH SATURDAY/... At 500 MB across NOAM and environs we still a pattern that gradually favors warmer and more humid conditions, although nothing that I would call hot through next week. We will near the boundary of the sub-tropical over the Atlantic and the jest stream to our N, so we can expect some rounds of SHRA/TSRA, but no significant widespread events. However, on Monday we will start off less warm, but still not out of ordinary summer temp ranges. There is a little convergence in central and S NH as NE flow runs into a bot of dead flow over S New England, so will see more clouds here, and maybe a couple showers Monday afternoon, but I think this area Is still partly sunny, with mostly sunny skies to the N and E. Highs will mostly be in the 70s. Monday night will be the coolest of the stretch with clearing skies and light winds. Expect lows in the upper 40s in some mtns pots and generally low to mid 50s elsewhere. Tuesday looks mainly sunny and dry with low humidity, as high pressure crosses the region, and highs 80-85, but cooler along the mid-coast. Flow shifts SW as the sfc high shifts offshore, and the resultant return flow will bring in more humid conditions. Wednesday looks mainly dry though, but with partly sunny skies and highs 80-85 once again. A weakening cold front moves in from the NW Wed night, and loses its steam over the CWA, so some SHRA and maybe some TSRA are possible Tue night into early Thursday, but expect clearing skies and warm and humid conditions on Thursday. Weak high pressure moves in for Friday, so its be dry, but still warm and humid. Next weekend remains uncertain as we sit beneath weakly anticyclonic flow and troughing to our W, which the means the potential waves and rounds of convection, but it should stay on the warm and humid side. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... Short Term... Summary: Deteriorating conditions expected through tonight as a warm front crosses the region with showers and a few embedded thunderstorms. Showers end Sunday morning...with another round of showers and strong to severe thunderstorms in the afternoon before partial clearing Sunday night. Restrictions: MVFR CIGS are building across the terminals this afternoon as showers arrive from the west. Expect deterioration to IFR or low MVFR this evening and overnight with low CIGS and some fog development. Improvement to VFR is expected on Sunday morning with showers/thunderstorms bringing additional restrictions in the afternoon. Some fog development is possible HIE/LEB Sunday night with restrictions possible here. Winds: Southerly winds 10kts will continue through tonight before shifting southwest and increasing to 12g18kts for the day Sunday. Winds turn northwest less than 10kts behind the cold front Sunday night. LLWS: Southwesterly winds in the 1.5-2kft layer strengthen to 40- 50kts with LLWS expected overnight tonight. This will end Sunday morning with no additional LLWS through Sunday night. Lightning: Very isolated thunderstorms are possible for the overnight. On Sunday...chances for thunderstorms increase for the afternoon with the potential for thunder throughout the terminals in the 18Z-00Z timeframe. Some of these storms could be strong to severe with damaging winds. No lightning is expected Sunday night. Long Term...VFR expected Monday through Wed, with possible valley fog Monday night. Then more widespread flight restrictions possible Wed night into early Thu in SHRA/TSRA and some fog. && .MARINE... Short Term...SCA conditions due to both winds and waves are expected to continue through Sunday ahead of an approaching cold front. Winds shift slowly shift northwesterly and diminish Sunday night...though residual SCA waves will likely persist through the first half of the night. Long Term...Generally light flow is expected through the middle of the week with winds and seas staying below SCA levels, but it could pick up some Wed night or Thu. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 11 PM EDT Sunday for ANZ150>154. && $$ SYNOPSIS... NEAR TERM...Arnott/Ekster SHORT TERM...Cempa LONG TERM...Cempa AVIATION... MARINE...
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
903 PM CDT Sat Jun 29 2024 .KEY MESSAGES... - There is a 20 percent chance for thunderstorms south of I-72 late this evening. The strongest of the storms will pose a risk for locally strong wind gusts and heavy rain leading to ponding of water in urbanized areas. - Seasonably hot and humid conditions make a return Wednesday-Friday with heat indices likely (50-70%) reaching 100 degrees or greater for locations south of I-72 on Wednesday. - Multiple chances for thunderstorms also return with a 40-50% chance on Wednesday and a 60-70% chance on Thursday. Outdoor activities could be impacted, especially due to the threat of lightning. && .UPDATE... Issued at 902 PM CDT Sat Jun 29 2024 A cold front was located across central IL from around Danville to Jacksonville as of 8 PM slowly migrating southward. The central IL portion of the frontal zone is becoming increasingly inactive with respect to thunderstorms, however around 3000 J/kg MLCAPE instability and 30 kt effective bulk shear was located ahead of the front according to RAP-based analysis. More pronounced disturbances along/ahead of the front from OK into MO, as well as KY into OH while lift was lacking across central IL, however likely contributing to the lack of thunderstorm activity here. Nevertheless, high resolution models continue to advertise at least isolated activity through midnight so have maintained slight chances south of I-72, shrinking down south of I-70 by midnight. Otherwise, cooler lows ranging from 56 in Galesburg to 70 in Lawrenceville look on track for tonight, with winds becoming northerly around 10 to 12 mph with gusts to 20 mph. 37 && .SHORT TERM... (Through Late Sunday Night) Issued at 257 PM CDT Sat Jun 29 2024 Our morning thunderstorms have now departed to Indiana, with a bit of capping building in their wake to limit convective potential for at least the next couple hours. however, given 2500-3500 J/kg MLCAPE (highest across our northeast) and PWATs near/over 2 inches per SPC`s mesoanalysis, water-laden microbursts capable of torrential rain, small hail, and especially localized damaging wind gusts remain a concern through evening with the strongest cells that develop along the southeastward-moving cold front currently situated near the I-55 corridor. This front will become more organized as it surges southward late this evening, bringing a sharp gradient (and rapid change with time at any given location) in theta-E (nearly 1 degK/km) and uptick in northwest winds which could gust close to 30 mph. Went with a blend of HRRR and NBM for overnight lows, which are forecast to fall into the 50s northwest of the Illinois River but remain close to 70 south of I-70 where the front will not arrive until between roughly midnight and 3 am. The continued cool advection will prevent temps from rising above the 70s tomorrow for most, if not all, of the CWA, making it feel more like mid May than late June and offering a much needed reprieve from the oppressive humidity. Temps dip further tomorrow night as winds drop off and in the absence of clouds radiational cooling is optimized. Around 60-80% of HREF membership brings Monday morning lows into the 40s outside of urban areas, though NBM, which is calibrated to climatology, suggests those chances are closer to 10- 20% with the ensemble mean in the low 50s; we`re going to maintain forecast lows closer to NBM mean for now, but wouldn`t be surprised if we wind up on the cooler side of things if tomorrow`s highs don`t overachieve (which sometimes happens with so much sunshine) and we wind up with both as little wind and as few clouds as currently forecast. Bumgardner .LONG TERM... (Monday through Next Saturday) Issued at 257 PM CDT Sat Jun 29 2024 On Monday, a mid to upper level ridge will be centered over the area with its associated surface high over the Great Lakes region. This will lead to a clear, calm, and somewhat chilly start to Monday with temperatures in the low 50s to upper 40s, while highs will only reach the upper 70s Monday afternoon. As the mid to upper level ridge axis passes through, our area will return to a deep southerly flow regime, leading to the return of summertime heat and humidity by Tuesday. A vast majority of the LREF guidance depicts the center of this ridge (with 500mb heights of 596dm) settling over the SE CONUS next week, placing our region on the northern edge where waves of shortwave energy will traverse. A weak upper level trough will pass along the northern Great Plains and deamplify as it progresses eastward just north of our region on Wednesday. The shortwave energy and its attendant, weak, cold front approaches from the NW on Wednesday, bringing with it the next chance for some rain, especially in the northern portions of the area where there is more sufficient column moisture present. Some of the deterministic model guidance depicts this weak cold front stalling out near our area Wednesday into Thursday, likely due to the 596dm ridge to our SE keeping the front from progressing to the SE of our region. The stalled front will essentially act as a runway for any waves of precip or convection that traverse around the 596dm ridge, potentially leading to flooding concerns depending on where this sets up at on Wednesday. Wednesday still appears to be the warmest day next week with highs in the lower 90s and heat indices nearing 100 degrees south of I-72, where the later frontal passage is at. However, high temps on Wednesday will be highly dependent on the exact timing of this weak cold front, which at this time is uncertain. Perhaps the better and more widespread chance of rain will be on Thursday (the 4th of July) as shortwave energy pivots around the 596dm ridge into the CWA, resulting in likely PoPs for most of the area. Uncertainty regarding the strength and position of the strong ridge remains after Thursday next week as an upper level trough may dig into the Upper Midwest, potentially deamplifying the upper level ridge. Regardless, our current forecast has highs in the 80s and lows in the 60s, but given the current ensemble spread there is low confidence this far out. Peine && .AVIATION... (For the 00z TAFs through 00z Sunday Evening) Issued at 637 PM CDT Sat Jun 29 2024 A cold front will press south of KSPI-KDEC-KCMI by 01Z, with associated showers and thunderstorms ending to the north of this front. Skies will gradually clear this evening, with VFR conditions expected through 00Z Monday. Winds becoming N-NW 8-14 kts with gusts 20-25 kts by 01Z-02Z, then gusts diminishing by 06Z-12Z. 37 && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$
Area Forecast Discussion
National Weather Service Louisville KY
847 PM EDT Sat Jun 29 2024 .KEY MESSAGES... * Very warm and muggy this afternoon with heat index readings peaking around 100 to 105. Scattered storms possible through the evening with torrential rainfall, gusty winds, and lightning being the main threats. * Another period of unsettled weather returns to the region by late Wednesday and Thursday. && .UPDATE... Issued at 846 PM EDT Sat Jun 29 2024 Widely isolated showers and storms continue this evening across the region. We may continue to see isolated activity pop up tonight into early tomorrow morning as a weak front approaches from the north. The convection thus far within our CWA has been relatively mild likely due to marginal mid-level lapse rates and weak capping in the 850-700mb layer. Still can`t rule out an isolated stronger storm overnight, but conditions will become less favorable for robust convection the deeper we go into the night. Forecast remains on track. && .SHORT TERM /THROUGH SUNDAY/... Issued at 344 PM EDT Sat Jun 29 2024 Afternoon satellite imagery and observations reveal partly sunny skies across the forecast area. Temperatures were in the upper 80s to the lower 90s. Dewpoints continued to hold in the lower-mid 70s resulting in heat indices in the upper 90s to the lower 100s (generally 98-104). The area remains generally devoid of convection with the exception of a line of shallow showers over across Garrard and into Madison county. Other storms were located up to our north along the I-70 corridor. With temperatures in the upper 80s to the lower 90s and dewpoints in the low-mid 70s, instability has ticked up across the region with MLCAPE values surging into the 1500-2500 J/kg range, with slightly larger values of SBCAPE locally. While instability is decent, low- mid level lapse rates and deep layer shear remain rather marginal and the best synoptic scale forcing is off to our northeast. For the remainder of the afternoon, isolated-scattered storms could develop over the region. Current thinking is that our northeastern sections would have the highest chance of seeing convection. Temps will top out in the upper 80s/lower 90s before cooling into the 80s by evening. An MCV evident WV imagery coming into central IN may spark a round of shower/storms this evening across the region. HRRR has been trying to drum up some convection mainly over the Bluegrass, but approaching MCV/wind shift over IL/MO may be enough to kick up some storms this evening. For now will continue to keep 30/40% PoPs going. Main threats with any storm will be torrential rainfall, gusty winds, and frequent lightning. Surface cold front will continue to push southward overnight and some additional convection may fire along that boundary. However, most CAMs keep the most significant convection to our west/southwest. Another warm night of temperatures is expected with readings only dropping into the mid-upper 70s. For Sunday, surface frontal boundary is forecast to drop through the region. This will bring cooler and less humid conditions to the area. We may see some scattered showers along the front in the morning across the north and then a few showers/storms could continue through the afternoon across the south as the boundary continues toward the TN valley. Highs will only warm into the upper 70s/lower 80s across southern IN with lower 80s (80-85) across Kentucky. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... Issued at 344 PM EDT Sat Jun 29 2024 By Sunday night, the cold front will be south of the region. Surface high pressure, centered over the Midwest, along with upper ridging will quickly clear skies over the Lower Ohio Valley. Cold air advection from northerly winds on the eastern side of the high will help drop low temperatures into the low 50s (southern Indiana) to the low 60s (southern Kentucky) which is 15-20 degrees cooler than Saturday night`s lows. The continued CAA will help to limit highs on Monday to the upper 70s to low 80s. The cold front followed by northern winds will also help knock dew points down into the 50s which will help make things feel much more comfortable throughout southern Indiana and central Kentucky, but as the center of the surface high gets pushed across the Great Lakes, return flow will begin lifting temperatures back into the 90s by Tuesday. This will also begin lifting dew points across the region as Gulf of Mexico moisture begins to get funneled up the Mississippi and Ohio River Valleys. Dew points in the 60s will return on Tuesday before the 70s on Wednesday. Upper 80s to low 90s are expected to remain into the weekend, and with the pressure gradient between the surface high on the East Coast and the approaching cold front to our northwest increasing, warm air advection and moisture transport will increase. This will push highs into the mid 90s and dew points into the mid 70s which will result in heat indices in the 100-104 range over the western half of the CWA. Currently, this looks to be be the hottest day of the week. By Wednesday night, an approaching cold front being pushed by an upper trough will push the upper ridge out of the Great Lakes region and through New England, leaving more zonal upper flow north of the upper high over the South. This will likely cause the cold front to flatten from west to east north of the high to the south. This will likely place the front just north of the CWA. In an environment with precipitable water values climbing over 2", shower and thunderstorm chances will begin increasing before the front gets pushed south of the region by Friday or Saturday. && .AVIATION /00Z TAFS THROUGH 06Z MONDAY/... Issued at 700 PM EDT Sat Jun 29 2024 Very isolated shower/storm activity has developed ahead of a weak cold front this evening but will likely avoid TAF sites through the overnight hours. Should one of these showers/storms impact a TAF site, expect briefly reduced cigs/vis and gusty winds. The wind shift associated with the front will pass through the region early tomorrow morning. Post-frontal northwest winds could get gusty at times during the afternoon and near 20kts. In addition to the winds, some low-end VFR to high end MVFR stratus may accompany the front for several hours before clearing out tomorrow afternoon from northwest to southeast. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ UPDATE...DM SHORT TERM...MJ LONG TERM...KDW AVIATION...DM
Area Forecast Discussion
National Weather Service Tallahassee FL
852 PM EDT Sat Jun 29 2024 ...New UPDATE... ...INSTANCES OF FLASH FLOODING FROM HEAVY RAIN ARE POSSIBLE THIS EVENING IN PARTS OF SW GA DOWN TO THE FL STATE LINE... .Correction...Added content to the Marine section .UPDATE... Issued at 843 PM EDT Sat Jun 29 2024 Clusters of slow-moving thunderstorms with embedded heavy rain rates have been ongoing this evening across parts of SW GA just east of the AL border down to northern Leon County. Instances of flash flooding are possible with this activity over the next couple hrs or so as these cells gradually track eastward. If you are under a Flood Advisory of Flash Flood Warning, please avoid any flooded roads, which are especially difficult to see at night. Convection likely persists for the first half of tonight before diminishing after midnight, per the latest HRRR run. Therefore, the main changes to tonight`s forecast were increasing rain chances where the axis of highest precipitation is currently in place and added the explicit mention of "heavy rain" in our hourly wx grids that coincide with definite PoPs of around 90% or more. Hourly temperatures on the front end were adjusted as well to account for the rain-cooled air mainly across the western half of the Tri-State area. && .NEAR TERM... (Through Sunday) Issued at 330 PM EDT Sat Jun 29 2024 Ridging aloft continues nudging in from the west through the near term with a moist unstable airmass remaining in place over the forecast area. Garden variety pop up storms are possible areawide tomorrow with PoP`s generally maxing out in the 60-70% areawide. PWAT`s ranging from 2.2-2.5" support efficient rainmakers, hinting that a localized nuisance / flash flooding threat is possible with these storms if they are slow moving and / or stall. Heat remains a concern as well tomorrow, though there are some caveats. Heat indices across our FL counties generally range from 108-112 with a few areas even reaching 113+, supportive of a heat advisory. However, given the large coverage of storms tomorrow during peak heating, rain cooled air with scattered anvil debris from these storms may hinder most of the areas from realizing these temperatures. Our SE AL and SW GA counties have heat indices > 108 as well, particularly in their counties bordering FL, though uncertainty remains the same. Regardless, temperatures are expected to once again be hot and muggy tomorrow afternoon. Make sure to wear light clothes tomorrow, drink plenty of water, and limit time outside if possible. Tonights low temperatures are expected to drop to the mid to upper 70s with afternoon highs tomorrow reaching the mid 90s. && .SHORT TERM... (Sunday night through Monday night) Issued at 330 PM EDT Sat Jun 29 2024 The short term period looks a bit unsettled with mid to upper level ridging pushing over to the west and a weak front stalling out over the area. How far south the front makes it is unclear at this point, but it will likely create a local focus for shower and thunderstorm activity With the most coverage expected Monday afternoon and evening. A few strong storms will be possible along with isolated pockets of heavy rainfall. Highs are forecast in the low to mid 90s, however areas with the highest coverage of rain and clouds may end up a few degrees below that. Lows are forecast in the mid 70s. && .LONG TERM... (Tuesday through Friday) Issued at 330 PM EDT Sat Jun 29 2024 Ridging begins to build back overhead during the long term, gradually lowering our rain chances through mid week. A few showers and storms will still be possible, particularly along the seabreeze in the afternoon, but widespread convection is not expected once the ridge settles in. This will also allow temperatures to soar once again, reaching the mid to upper 90s again by the end of the week. Lows are forecast to remain fairly steady in the low to mid 70s. && .AVIATION... (00Z TAFS) Issued at 703 PM EDT Sat Jun 29 2024 Shower and thunderstorm activity today will begin to diminish after sunset with the remaining storms ending around 04Z-06Z. During the overnight hours, winds will become light to calm. It is possible for patchy fog to develop at our inland terminals but confidence is too low to include in the TAFs. Showers/thunderstorms may develop in the late morning into early afternoon; however showers and thunderstorms are more likely expected to return during the afternoon Sunday, hence VCTS at all terminals, with higher confidence around 20z for TSRA at most terminals. && .MARINE... Issued at 331 PM EDT Sat Jun 29 2024 Offshore buoys were reporting SW winds near 10 kts with 2-ft seas and a dominant period of 4-5 seconds this evening. From CWF Synopsis...Wave periods notably increase overnight via southerly swells with an uptick in seas. Southwesterly flow around 10 knots and seas around 3 to 4 feet will prevail through most of the weekend until a weak frontal boundary pushes into the Gulf and winds become light and variable early next week. Wave heights of 3-4 feet will predominantly be attributed to the tropical disturbance in the southern Gulf of Mexico that is currently crossing the Yucatan Peninsula. Scattered showers and storms are expected through the weekend and early next week with activity generally greatest in the overnight and early morning hours as the diurnal land breeze circulation is at its peak. && .FIRE WEATHER... Issued at 331 PM EDT Sat Jun 29 2024 Tomorrow, isolated storms are expected to occur across the area in the afternoon hours with gusty and erratic storms near and within them. This will continue over the next few days as a moist and unstable airmass remains over the forecast area. Transport winds over the next few days will be variable in direction ranging from around 5-10mph with increasing mixing heights each afternoon. Fair to generally good dispersions are expected areawide. At this time, there are no fire weather concerns at this time. && .HYDROLOGY... Issued at 243 AM EDT Sat Jun 29 2024 Widespread forecast rainfall totals through the next 5 days are generally expected to remain around 1-2 inches, with locally higher totals possible. This is primarily due to deep tropical moisture remaining in place over the region through the middle of next week. There are currently no flooding concerns at this time; however, localized flash flooding from training thunderstorms will be possible, especially in poor drainage and urban environments due to very efficient rain processes and high rainfall rates. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 77 93 76 93 / 80 70 40 70 Panama City 80 91 78 92 / 30 70 50 60 Dothan 76 93 75 95 / 60 70 30 50 Albany 76 94 75 95 / 60 70 30 60 Valdosta 76 94 76 94 / 60 70 30 60 Cross City 76 93 75 91 / 50 70 40 60 Apalachicola 80 91 78 88 / 30 70 50 50 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk until 8 AM EDT /7 AM CDT/ Sunday for FLZ108-112-114. GA...None. AL...None. GM...None. && $$ UPDATE...IG3 NEAR TERM...Worster SHORT TERM...Merrifield LONG TERM....Merrifield AVIATION...Montgomery MARINE...Merrifield FIRE WEATHER...Worster HYDROLOGY...Bunker
Area Forecast Discussion
National Weather Service Tucson AZ
128 PM MST Sat Jun 29 2024 .SYNOPSIS...Active monsoon pattern this weekend into early next week bring daily chance of showers and thunderstorms. Some storms will generate strong winds and locally heavy rainfall. && .DISCUSSION...Latest visible satellite imagery early this afternoon is still showing quite a bit of mid level clouds across most of southeast Arizona as an MCV is pushing north from Santa Cruz/SW Cochise County. This cloudiness has kept temperatures from warming up as quickly as usual today and depending on how much persists into the mid afternoon hours, may keep Tucson below 100 degrees today. It`ll be a close call. Not much on radar at this time with just a few light showers mainly east of Tucson. Given the placement of the MCV and subsidence behind it as the MCV pushes north, convective development is on the slow side today. Latest HRRR shows a few storms mainly west of Tucson through the afternoon and this is where more abundant solar insolation has occurred today. Elsewhere, a continuation of some scattered shower activity with perhaps an embedded thunderstorm or two that could produce brief heavy rain. All in all, certainly a much quieter afternoon period than what we experienced yesterday. Heading into this evening and the overnight hours, our focus shifts toward the disturbance currently seen on WV imagery over Chihuahua that is pushing to the west-northwest. This will help trigger convection across NE Sonora/NW Chihuahua early this evening that will push to the northwest later in the evening and overnight hours. The convection will be aided by the deep layer lift from the aforementioned disturbance, along with outflow boundaries acting on elevated CAPE. Don`t be surprised if you hear rumbles of thunder in Tucson in the midnight to 3 am time frame. This area of convection will also help reinforce the deep moisture over our area. Latest HRRR/CAMs show convection winding down around or shortly after 12Z. Sunday into Sunday night is shaping up to be a very active period. Sunday morning cloud cover should diminish fairly quickly as 15 to 20 kt southeasterly flow aloft pushes clouds from the overnight convection away and allows the atmosphere to reload. The combination of increasing instability (MLCAPE at or above 1000 J/KG in many locales), and another disturbance approaching aloft will set the stage for widespread shower and thunderstorms Sunday afternoon into evening. Most of the forecast area is at risk for these storms, though the focus for the strongest storms and greatest flash flood risk will be from western Cochise County to points westward including Tucson Metro and into the Tohono O`oodham Nation. HREF 3 hour QPF 40km neighborhood probabilities exceed 70% for 1 inch or and around 10% for 3 inches or more near the Tucson Metro. WPC has the area referenced above already outlined in a slight risk for excessive rainfall and that continues to look good. Greatest concern for flash flooding will be due to storm mergers/clustering as individual storm motion will be around 15 mph. Later shifts will need to consider hoisting a Flash Flood Watch for portions of the forecast area. There is also a threat for strong gusty outflow winds Sunday afternoon into evening, especially from Tucson and point north and westward where DCAPE values exceeding 1500 J/KG will assist in the development of these strong outflows. HREF members are all in agreement of this scenario with strong outflows pushing NW across Pinal County which would result in areas of blowing dust. This is also something we`ll be monitoring. The disturbance that is expected to result in the widespread convection Sunday will move to our north by Monday with the flow aloft a bit more from the south to southwest. We`ll have to see just how worked over the atmosphere is and how much subsidence there is on Monday for less convective activity. Given the flow pattern, the focus will tend to be on areas from Tucson eastward. The active and moist pattern will continue into the middle of the week and through July 4. However, it`s a little bit challenging to discern the more active days/locations at this time. By Friday and into next weekend as the high aloft reestablishes itself and strengthens to our north, our flow pattern will be more from the NE/ENE and this would be more favorable to bring storms in off the Mogollon Rim/Gila Mtns, a pattern we have yet to see this monsoon. && .AVIATION...Valid through 01/00Z. SCT-BKN clouds at 8-12k ft AGL thru the fcst period. SCT-SHRA/-TSRA with brief MVFR conds nr storms, most likely between 30/03Z and 30/11Z and then again aft 30/20Z. SFC winds 10 kts or less with the occasional afternoon gusts, except stronger due to gusty outflows from storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Relatively deep moisture will stick around through the forecast period. This will bring scattered thunderstorms and showers this afternoon and especially tonight with an uptick in thunderstorms Sunday afternoon/evening. Next week will see daily chances of afternoon and evening showers and thunderstorms. Strong erratic gusty winds of 40 mph or higher can be expected with any storm development, along with locally brief heavy rainfall. Outside of thunderstorm winds, 20-foot winds will generally be 15 mph or less each afternoon with the occasional gust of 20 mph. Min RHs will generally be around 20% in the valleys and 30s in the mountains with good overnight recoveries. && .CLIMATE...The triple-digit high streak for Tucson, which currently stands at 33 consecutive days, is at risk today thanks to yesterdays two brief heavy rain events that hit the airport and cloud cover. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson