Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/03/23


AREA FORECAST DISCUSSION
National Weather Service Albany NY
1032 PM EDT Sun Jul 2 2023 .SYNOPSIS... Slow moving low pressure approaching from the west will bring periods of rain and thunderstorms through Monday, with locally heavy rain possible. Scattered showers and thunderstorms are expected for Independence Day, with improving weather and warmer temperatures arriving for mid week. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... As of 11pm...Our sfc low is now pushing into the Catskills per the latest RAP sfc analysis with its upper deformation now over the I-90 corridor supporting an organized area of steady rain. Latest MRMS and sfc observations show rainfall hourly rainfall rates near 0.25 - 0.40 inches in Schoharie County extending into western Albany County so a period of moderate rainfall is likely as the deformation area tracks eastward through 03 - 04 UTC. Further south, a somewhat organized cluster of convection is extending in Ulster County into Dutchess which is coincident with the pseudo cold front of the incoming sfc low. While ground truth stations show little wind reaching the sfc, velocity signatures in the mid-levels are little more ominous so we are maintaining a watchful eye for brief strong wind gusts as this cluster tracks eastward over the next hour or so. Heavy rain is falling within these clusters with some NYS mesonet sites picking up 1 inch of rain in under an hour; however, with little rain in its wake, we held off on any flood advisory products. The bulk of the rain will be around through 06 UTC or so before ending from west to east. Very mild and muggy night ahead with little temperature change. Previous discussion...An organized area of rain associated with the upper deformation of an approaching low currently positioned over the Southern Tier is tracking through the Schoharie Valley, Mohawk Valley, and eastern Catskills. This rain is quickly spreading eastward through the Greater Capital Region and mid- Hudson Valley and continues pushing eastward into western New England. Dew points remain in the upper 60s to low 70s so it is very muggy outside and will remain as such through tonight. With the lose of daytime heating and thickening cloud coverage, overall instability has decreased. However, some pockets of moderate to locally heavy rain may occur overnight, especially where any isolated thunderstorms occur. The sfc low and upper deformation should track along the weak surface boundary that lays just south of I-90 and exit into New England by 06 - 09 UTC. This should bring an end to the rain from west to east, although areas closer to I-90 including the Greater Capital District and the Berkshires, could hang to rain a bit longer given closer proximity to the sfc boundary. This is why we kept likely and categorical POPs here through 09 UTC while areas to the south and north trend to chance POPs earlier. Overall, rainfall totals tonight should range 0.25 - 0.75 inches with locally higher amounts possible where thunderstorms occur. Although many areas already received 0.50 - 1.00 of rain already from daytime rain/storms, this rain should fall over 3 - 5 hours and the additional rainfall should not be enough to push areas over 3 or 6 hr flash flood guidance. We will closely monitor any embedded convection as locally heavy downpours persisting over an area could lead to localized flooding. Lows tonight in the mid 60s to around 70. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... A well defined upper impulse currently in the OH Valley will track into our region later Monday into early Tuesday. Another threat for thunderstorms with locally heavy rain and gusty winds is expected Monday afternoon and night as some periods of sun in the afternoon will warm temperatures well into the 70s to lower 80s, with a few mid 80s mid Hudson Valley. The warm temperatures and the deep moisture will once again result in CAPES around or above 1000 j/kg in some areas but shear will be weak. Midlevel lapse rates are weak. Another boundary layer wind shift and small jet core will provide some extra low level forcing. So, showers and thunderstorms likely Monday afternoon and evening, again, with potential locally heavy rain and gusty winds. Rain decreases in coverage Monday night as the upper energy and low level forcing begins to exit. By Tuesday, there will still be some weak upper energy on the western periphery of positively tilted upper troughing that will be slow to exit. Deep moisture will be slowly exiting as well. However, there will be enough warming and moisture Tuesday for more showers and thunderstorms from late morning through the afternoon. On Tuesday, once again, there could be periods of sun that help temperatures warm into the lower to mid 80s, with upper 70s to around 80 in higher terrain. Low level forcing and instability will be weaker than on Monday, and the deeper moisture will continue to exit slowly, so the threat for locally heavy rain and severe weather should be minimal. Any showers and storms should end Tuesday night with increasing sunshine Wednesday. Only isolated showers and storms possible Wednesday afternoon. Highs Wednesday well into the 80s to near 90 with around 80 to lower 80s higher terrain. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... Warm to hot, humid, and a continued active/wet weather pattern can be expected through the long-term forecast period. We start off the extended on Thursday with a surface high and mid-upper ridge axis in place over the region. Mostly sunny skies and a return flow from the southwest will aid in a hot and humid day with high temperatures climbing into the upper 80s to lower 90s along the river valleys. This coupled with dewpoints in the upper 60s will result in apparent temperatures (heat indices) in the mid 90s along the river valleys, which will be right around Heat Advisory levels. Will have to continue to keep track of these trends for the potential issuance of heat headlines. Beyond Thursday, forecast models/ensembles continue to signal the return to wet weather Friday into next weekend as a storm system over the central U.S. is expected to approach the region bringing renewed day-to-day chances for showers and thunderstorms. The best chance for rain looks to be Friday and Saturday. However, there is a chance that rain could linger into Sunday depending on how the system evolves. Given that precipitable water (PWAT) values will be +1 to +2 STDEVS and dewpoints still in the 60s and 70s, there is the potential for moderate to heavy rainfall over the area during this time. Will also have to monitor the potential for excessive rainfall over the area during this time. Temperature anomalies will be warmer/hotter than normal for the balance of the period though we are expected to see things trend closer to normal levels. High temperatures on Thursday are progged to climb into the upper 80s to lower 90s along the river valleys upper 70s to mid 80s higher elevations). On Friday, high temperatures are expected to climb into the mid to upper 80s along the river valleys. On Saturday and Sunday, highs are forecast to reach the lower to mid 80s along the river valley (cooler higher elevations). Overnight low temperatures are expected to mainly be in the 60s with some 50s in the higher elevations especially Friday night through Sunday night. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... Through 00z Tuesday....Main weather concerns for the terminals are 1) round of showers this evening into tonight that could reduce cigs/vsbys down to MVFR/IFR levels, 2) low stratus/mist this evening/tonight possibly lingering into Monday morning, and 3) another round of showers and thunderstorms Monday afternoon into Monday evening that could also briefly reduce cigs/vsbys to MVFR/IFR levels. The first round of showers associated with a shortwave riding along a quasi-stationary frontal boundary draped across the FA is moving into ALY`s area, per the latest radar scans. This first batch of showers is expected to stick around through this evening before coming to an end late tonight from west to east roughly between 05z- 09z. Fog is not expected to be a concern due to the abundant presence of cloud cover. However, MVFR mist/low stratus could be something to contend with later this evening and especially tonight due to the abundance of low level moisture. Low stratus/mist could linger into Monday morning. The main uncertainty at this time will be if/when will the mist/low stratus break. After a period of dryness Monday morning, a second round of showers and thunderstorms is expected to develop. Coverage is expected to be scattered, but enough to include PROB30s for the TAF sites to take into account this potential. Any shower or thunderstorm that passes over a terminal will have the capabilities of briefly reducing cigs/vsibilities to MVFR-LIFR levels. Winds are expected to be light and variable for much of the 00z TAF period. There is the potential for there to be a slight southerly component at around 5 kts during the day on Monday. Outlook... Monday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Independence Day: High Operational Impact. Likely SHRA...TSRA. Tuesday Night: Low Operational Impact. Isolated SHRA. Wednesday: Low Operational Impact. Isolated SHRA...TSRA. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Low Operational Impact. Slight Chance of SHRA...TSRA. Thursday Night: Low Operational Impact. Slight Chance of SHRA. Friday: Moderate Operational Impact. Likely SHRA...TSRA. && .HYDROLOGY... Multiple rounds of showers/thunderstorms containing heavy rainfall are expected this evening into tonight. Where these occur, some minor flooding of urban/poor drainage areas is likely, and isolated to scattered flash flooding is possible where the more frequent heavy downpours occur. WPC has placed most of the region within a slight risk for excessive rainfall for this period. Additional showers/thunderstorms with locally heavy downpours are expected Monday into Tuesday, especially during the afternoon hours. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...NAS/Speciale NEAR TERM...NAS/Speciale SHORT TERM...NAS LONG TERM...Evbuoma AVIATION...Evbuoma HYDROLOGY...
Area Forecast Discussion
National Weather Service Binghamton NY
919 PM EDT Sun Jul 2 2023 .SYNOPSIS... Widespread showers over Central NY and NE PA will taper off through the evening, with a shower or two lingering in Central NY through early tomorrow morning. Additional bouts of rain expected again on Monday as a frontal boundary stalls across the area. Locally heavy rainfall and isolated flash flooding will be possible. Drier conditions are expected for Tuesday and Wednesday. && .NEAR TERM /THROUGH MONDAY NIGHT/... 915 PM Update... No major changes to the near term forecast; blended observations into the forecast. Widespread showers continue for Central NY and parts of NE PA, and will taper off through the evening. 630 PM Update... Widespread showers can be seen blanketing the radar currently. These showers are expected to continue through the evening, with some lingering showers in the northern Central NY. No major changes to the near term forecast besides lowering some of the high temperatures in Central NY tomorrow by 1-2 degrees. Otherwise, blended observations into the forecast. 331 PM Update... Upper level disturbance with a weak surface low is rolling across northern PA, with widespread light showers moving into Central NY and NE PA. Convection has sprouted up since the last discussion update, mainly just ahead of the low in Central PA and parts of the Southern Tier and up into Cortland County. Additional convection has formed along a deformation axis south of Lake Ontario, but so far this has stayed outside the CWA. The relative lack of rainfall yesterday afternoon/evening makes us overall less susceptible to flash flooding today/tonight, but localized trouble spots could still develop, especially in poor drainage areas. RAP analysis sounding at ITH had PW of 1.80 inches, and warm cloud depth just over 10,000 feet. This system looks to roll east of the area around Midnight to 2 AM, with low clouds and areas of fog likely developing in its wake. A stalled out frontal boundary will remain across the area tomorrow. Another upper level disturbance, currently moving into Indiana, will roll across the area tomorrow, with additional scattered/numerous rain showers and embedded thunderstorms. PW values will remain just shy of 2 inches, with warm cloud depth of 10-11K feet. Again, isolated heavy rainfall and flooding could develop, especially over areas that receive a "priming" heavy rainfall tonight. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... 300 PM Forecast... An upper-level trough will slowly move through the region on Tuesday. There will be enough moisture and instability to support rain showers and afternoon thunderstorms. Model solutions are showing MLCAPE values of at least 1000 J/kg but this will be accompanied with weak shear, 20 kts or less. Given this environment, showers and thunderstorms will be relatively short-lived. For PoPs on Tuesday, a little bit of the NBM was blended in with the previous forecast to keep PoPs in just the chance category. Due to the expected short-lived nature and drier air filling in from the north throughout the day, coverage will likely be limited. Showers and storms will come to an end by Tuesday night as a ridge of high pressure moves in. Dry conditions are then expected to continue through the rest of the short term forecast period. An isolated shower/thunderstorm or two cannot be ruled out as a weak wave passes through, but moisture will be limited so chances will be slight chance at best. Conditions will be warm and muggy heading into midweek. Highs Tuesday will be in the upper 70s to mid 80s. By Wednesday, temps climb into the 80s across the region some valley locations will hover around 90. Dewpoints will be in the 60s both days. The overnight hours will bring little relief as temps only fall into the 60s. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 300 PM Forecast... The ridge of high pressure will remain over the region Thursday as it slowly drifts eastward. Ahead of an approaching cold front, showers and thunderstorms may develop Thursday afternoon and evening. This activity will be dependent on whether or not there is enough moisture present to support showers, as some guidance favors a dry solution until the front is closer. The better chance for showers and thunderstorms comes Friday and into the start of the weekend as the surface front enters the region. Guidance continues to show this front becoming quasi-stationary or even stalling over the region. However, there are still uncertainties on the timing, especially when it will finally push through. For now, will follow ensemble guidance and keep the best rain chances for late Friday. Hot and muggy conditions will continue into the later half of the week. With rain showers present and the cold front passing through, a cool down is expected to start the weekend, at least for the daytime hours. Nightly lows will likely stay on the warmer end. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... Low-end VFR and MVFR restrictions will likely persist as the showers rotate through the region this evening. Ceilings and vsbys are expected to drop to IFR and even temporarily worse tonight due to fog and low clouds. A batch of weak rain showers may push through quickly Monday morning around ELM, ITH and BGM before clearing out after 15Z. Low ceilings may persist through 18Z, but more widespread improvement is expected after 18Z. Showers will develop again in the afternoon across much of the region, but as a weak front slips south, so will the convection. At this time it appears the best chance for TS will be ITH south to AVP after 19-20Z. Confidence in timing and location is once again very low, so have just gone with PROB30 groups. Winds are fairly light and variable through the period...become more northwesterly Monday afternoon. Outlook... Monday Night through Tuesday...Isolated afternoon/evening showers and thunderstorms with associated restrictions. Wednesday...Mainly VFR. Thursday and Friday...Thunderstorms look to return Thursday or Thursday night, lingering into Friday with associated restrictions. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...KL/MPH NEAR TERM...KL/MPH SHORT TERM...BTL/JTC LONG TERM...BTL AVIATION...BJT/MPH
Area Forecast Discussion
National Weather Service Birmingham AL
1032 PM CDT Sun Jul 2 2023 ...New SHORT TERM... .SHORT TERM... (Rest of Tonight) Issued at 1015 PM CDT SUN JUL 2 2023 Coverage on the radar has decreased significantly and should continue this trend. Have adjusted pops downward accordingly. The heat advisory expired at 9 pm. Will be looking to see if another heat advisory is needed for Monday afternoon with the new guidance. If so, it would probably be for the SRN counties looking at the latest. Otherwise, the overnight lows are similar with only a few minor changes after obs/hires data has been added for tonight. 08 Previous short-term discussion: (This evening through Monday) Issued at 121 PM CDT SUN JUL 2 2023 Broad mid-level ridging has moved further east of the area while an upper low was positioned over North-Central Illinois with associated troughing further southwest over the Ozarks. Surface high pressure is positioned to our east along the Central and Southern Appalachians while a surface front extends from near Chicago, IL southwest to near Little Rock, AR and west across the Red River in the Central Plains. RAP mesoanalysis depicts multiple shortwaves over the Mid-South extending east to over the northern portion of the state. The area is experiencing strong low-level instability with temperatures in the 90s and dew points remaining in the 70s while mid-level ridging was centered over South Georgia. Today`s activity is not associated with a convective complex, but is rather more scattered in nature. However, we are experiencing higher than typical deep- layer shear today with 0-6 km Bulk Shear values over 20 kts generally near and north of the Interstate 20 corridor and even higher amounts to our west per RAP mesoanalysis. Sufficient wind shear will support storm organization and longer life cycles while the strong instability and sufficient dry air aloft will favor damaging wind and hail risk from the heavier activity today. The wet microburst risk is high today with the better potential across the northern and central counties. Most storms will produce gusty winds with some damaging winds possible from the heavier activity. This afternoon. A longwave trough advances further east toward the Lower Mississippi River Valley today while mid-level ridging broadens out further off to our east. Surface high pressure also becomes positioned further east while a surface front moves into the Western Ohio River Valley and extends southwest across the Mid South and back west into the Central Plains. A series of shortwaves aloft will move east over the northern portion of the forecast area with sufficient wind shear for some organized strong to severe storms. Strong low-level instability will support scattered showers and thunderstorm activity with highest activity across the northern portion of the area through mid afternoon, followed by more activity across the south as outflows from the north and west propagate into the area along with expected sea breeze activity pushing north through the afternoon hours. Some storms may be severe with damaging winds and hail due to high wet microburst potential in addition to higher wind shear than typical for this time of year. High humidity coupled with hot temperatures will continue to produce heat index values over 105 degrees with heat stress remaining a concern this afternoon into the early evening. Highs will range from the low 90s far east to the upper 90s south and central. Winds will be from the west at 5-10 mph. Tonight. A longwave trough will move over the Lower and Middle Mississippi River Valley Regions overnight while mid-level ridging persists off the Southeast Atlantic Coast and over the Four Corners States out west. Surface high pressure becomes positioned further southeast over Southern Florida while a surface front decelerates to our northwest over the Ohio River Valley extending southwest into the Mid-South Region. Continued scattered shower and thunderstorm activity will gradually shift from northwest to southeast through the evening as the sea breeze advances northward, fostering low-level convergence across the south to maintain activity later in time. A few strong to severe storms will remain possible with damaging winds and hail, though this risk will decrease with time after sunset. Lows will range from near 70 northeast to readings in the mid 70s south and west. Winds will become more southerly overnight with speeds from 3-6 mph. Monday. The flow pattern aloft becomes more zonal Monday though longwave troughing persists just to our north and northwest. Ridging remains positioned far to our east with another ridge remaining over the Desert Southwest. Surface high pressure will remain far southeast of us while the surface front will advance further south and east, extending from the Eastern Ohio River Valley southwest through the Mid-South Region. Chances for showers and storms will be more focused to the north and northwest through the morning hours, closer to the surface front to our northwest, then activity is expected to expand toward midday and into the afternoon hours across most of the forecast area due to existing boundaries from ongoing current convection. The overall weakness aloft with persistent strong low-level instability will continue to support instances of strong to severe storms from midday through early evening. Highs will range from the low 90s far east to the mid 90s south. Winds will be from the southwest at 6-12 mph. 05 && .LONG TERM... (Monday night through next Saturday) Issued at 307 PM CDT SUN JUL 2 2023 The previous forecast remains on track, with heat indices expected to reach as high as 100-105F Tuesday and Wednesday. Showers and thunderstorms are forecast each afternoon during the period, and this activity may work to limit the highest heat index values in areas receiving ample precipitation. PoPs and temps were tweaked with latest guidance, but the messaging of roughly 100F heat indices each day with strong to severe thunderstorms will continue for the next few days. 12 Previous long-term discussion: (Tuesday through Saturday) Issued at 336 AM CDT SUN JUL 2 2023 An active weather pattern will continue through the remainder of the week. Weak ridging in the lower levels persists across the Gulf States with an upper level trough to our north. The frontal boundary remains largely stationary to our north as well, providing at least some initial focus for convection each afternoon. For Tuesday, scattered to numerous thunderstorms are expected to develop, with some becoming strong to severe. Overall, deep layer shear is limited, so the main threat will be damaging winds with any downbursts, but we can`t rule out some hail with the stronger storms. Heat indices will reach into the 100-105 degree range Tuesday afternoon, though the extent may be limited by the timing and coverage of any thunderstorm activity. The pattern doesn`t change significantly through the end of the week. There are hints that at least a couple of shortwaves could swing through the upper level trough, leading to higher coverage of thunderstorm activity, but timing of those shortwaves is highly uncertain at this point. It`s likely that we see at least scattered to numerous thunderstorms each afternoon this week, with a few strong storms possible each day. 25/Owen && .AVIATION... (00Z TAFS) Issued at 740 PM CDT SUN JUL 2 2023 TSRA continue across a large portion of the SRN half of C AL as well as a cluster storm that developed near TCL that is moving EWD. Activity should begin to taper down after sunset. Another round is expected for Mon afternoon. Some MVFR cigs and MVFR/IFR vsbys are possible in storms. 08 && .FIRE WEATHER... Hot and humid conditions continue through the next few days, with afternoon and evening thunderstorms expected each day. Heat indices as high as 100-105F each day. Generally light westerly to southwesterly winds will persist through the next several days, up to 5-7 mph at times. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 70 93 69 89 / 50 50 30 60 Anniston 70 91 70 89 / 40 50 30 60 Birmingham 73 94 72 90 / 40 60 30 60 Tuscaloosa 73 93 72 91 / 40 60 30 60 Calera 73 92 71 91 / 50 60 30 60 Auburn 72 91 72 91 / 60 40 30 50 Montgomery 74 95 73 94 / 60 40 30 50 Troy 73 95 72 93 / 60 30 20 50 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...08/05 LONG TERM....12/25/Owen AVIATION...08
Area Forecast Discussion
National Weather Service Dodge City KS
846 PM CDT Sun Jul 2 2023 .UPDATE... Issued at 846 PM CDT Sun Jul 2 2023 Infrared satellite imagery and radar indicate a small MCS has developed as of 845 pm, centered on Kearny county. Earlier a marginal supercell produced 1-1.5 inch hail at Syracuse, along with outflow wind gusts near 60 mph. Reports from Kearny county and radar trends show wind/hail are falling below severe criteria, and a slow weakening trend is expected over the next 1-2 hours, with MCS maintenance only 30% in the prestorm environment. Increased pops for the very short term for the impacted zones, but latest HRRR iterations show the complex weakening rapidly this evening upon approach to Garden City. && .SHORT TERM...(This evening through Monday night) Issued at 140 PM CDT Sun Jul 2 2023 Throughout the short term discussion, an upper level shortwave will be moving through the Great Lakes region this afternoon through tonight then into the Northeastern United States tomorrow into tomorrow night. An upper level high will be found above the Desert Southwest with another upper level trough over eastern Canada digging into the Pacific northwest tomorrow. This will place southwest Kansas under northwest flow aloft. A weak shortwave is progged to move through this flow this evening above the Central Rockies, then through the Central Plains overnight into tomorrow. Towards the surface, lee troughing will develop across eastern Colorado shifting winds back to a southerly direction with mostly clear skies and dry conditions across the forecast area. This will change this afternoon when the atmosphere becomes unstable across far eastern Colorado, triggering thunderstorm development. These storms will cluster together during the early evening as they progress eastward. However, current indications show these storms to weaken as they move into western Kansas, dissipating after midnight. Nonetheless, the strongest storms could produce small hail and winds up to 60 mph. Otherwise expect an increase in cloudiness overnight with clearing from west to east towards morning. Lows by tomorrow morning look to range from around 60 degrees in far western Kansas to the upper 60s across central Kansas. The remainder of the short term forecast looks to be quiet with mostly clear skies and southerly winds. The only exception to this will be across central Kansas where a few clouds will be found with isolated thunderstorms possible in the afternoon. I think these storms should stay out of the forecast area. Highs tomorrow will reach into the low 90s with lows tomorrow night in the 60s. .LONG TERM...(Tuesday through Sunday) Issued at 140 PM CDT Sun Jul 2 2023 Moving on to the long-term period, the synoptic pattern will generally exhibit an upper-level high-pressure system over the Desert Southwest with an upper-level trough spanning the northwestern United States and the Northern Plains. Consequently, western Kansas will experience northwest-directed airflow aloft. A few disturbances will traverse between these two systems, enhancing atmospheric lift. The most potent disturbance will aid in pushing a cold front through western Kansas by Wednesday morning. There is a possibility of a few thunderstorms occurring along and behind the frontal boundary, although at present, it appears that most areas will remain dry. Moist, low-level upslope flow will develop north of the front along the southern periphery of the westerly winds, persisting for several days. This weather pattern is conducive to the formation of thunderstorm clusters over Colorado in the afternoon, with mid-level westerly winds likely guiding these clusters eastward and southeastward across western Kansas during the nighttime hours. Consequently, there is the potential for several rounds of thunderstorms across central and western Kansas from Wednesday night through Saturday night. It is impossible to accurately determine the precise locations of these storm clusters several days in advance. However, there is a potential for rainfall in certain areas. In addition, it is still too early to speculate on the severity of the thunderstorms or whether they will be elevated or surface-based. Nonetheless, considering the moderate mid-level airflow, persistent surface troughing, and the potential for a nocturnal low-level jet, severe storms cannot be ruled out. Regarding temperatures, highs on Tuesday will reach the 90s, followed by upper 70s in west-central Kansas and low 90s in south-central Kansas on Wednesday. These temperature predictions for Wednesday may change due to the timing of the cold front. Highs on Thursday are expected to reach only the upper 70s to low 80s as a result of this system, while Friday and Saturday will see temperatures in the upper 80s. Lows will generally be in the 60s, except on Wednesday and Thursday morning when upper 50s may be possible in northern Kansas around sunrise. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 430 PM CDT Sun Jul 2 2023 VFR will continue through this TAF cycle. Radar and satellite imagery at 2130z Sun depicted thunderstorms west of EHA, but they are struggling to make any eastward progress. Have very low confidence of convection reaching any airport, so kept TAFs largely dry. Did keep a VCTS/CB mention at LBL for a few hours this evening, but storms may likely remain W/SW of LBL. Otherwise, various amounts of cirrus anvil debris and light and variable winds will prevail through 15z Mon. Winds will trend light southerly at 10-15 kts after 15z Mon. && .PRELIMINARY POINT TEMPS/POPS... DDC 65 92 66 98 / 20 10 10 0 GCK 63 91 65 96 / 70 10 10 0 EHA 62 92 64 96 / 20 10 10 0 LBL 63 91 64 96 / 20 10 10 0 HYS 66 93 66 100 / 20 10 10 10 P28 69 93 67 99 / 20 10 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Turner SHORT TERM...Hovorka_42 LONG TERM...Hovorka_42 AVIATION...Turner
Area Forecast Discussion
National Weather Service Peachtree City GA
754 PM EDT Sun Jul 2 2023 ...New 00Z Aviation Discussion... .UPDATE... Issued at 734 PM EDT Sun Jul 2 2023 A round of strong thunderstorms is currently moving through northeast Georgia and is exiting the forecast area. However, we`re not out of the woods yet, as another cluster of thunderstorms has entered southwest Georgia from east Alabama, and is anticipated to spread northeastward over the next few hours. The warm and humid airmass ahead of this cluster remains mostly untapped, with SBCAPE values of as high as 3500 J/kg, a few storms could become strong to severe before the loss of diurnal instability tonight. Furthermore, with DCAPE values progged to be about 1000 J/kg, stronger storms that develop will still be capable of producing damaging wind gusts. Hail also cannot be ruled out. && .SHORT TERM... (This evening through Monday) Issued at 309 PM EDT Sun Jul 2 2023 Today and tomorrow will be a wash, rinse, repeat type of forecast days with summer type like convection occurring. Today energy moving through the main southwest flow aloft will lead to episodes of severe convection near a few stalled surface boundaries. Unfortunely this type of set up makes it difficult to spot exactly where convection will occur. So while we know the atmosphere is primed for isolated to scattered severe storms for the remainder of the afternoon and into the evening, determining the exact timing and placement remains difficult. If the CAMs are to believed (ARW seems to have verified better than some of the others this afternoon), scattered showers and storms will continue to evolve across our western borders and move east across the FA throughout the evening. Current mesoanalysis indicates decent deep layer shear, high instability (SBCAPEs 2000-3000 J/kg), lapse rates of 6-7km, 0-1 km SRH ranging from 150-200 m2/s and strong DCAPEs will likely result in severe storms containing hail and damaging winds along with heavy rainfall. Tonight into early tomorrow morning another potential round of rain showers and thunderstorms slides into our area from the west. This activity will be hinged upon how this evenings activity evolves. For now will note that should this activity develop as the short term guidance has been indicating then damaging wind gusts will be the main impact and the activity will likely be focused across norther GA. For now the HRRR remains the most bullish on this activity and illustrates storms occurring after 08Z tomorrow morning with less wide spread coverage than today. All of the above thinking has been highlighted by the SPC Day 1 Outlook, which outlines areas north of a line from Haralson to Hart counties in a Slight Risk (2 out 5) and much of central GA in a Marginal Risk (1 out of 5). Unfortunely, things do not end here...the heat continues. A heat advisory remain in effect through 8 PM tonight for the entire CWA with the exception of the far N GA counties. Another heat advisory is likely to be issued for tomorrow during the overnight forecast. Nonetheless...keep in mind heat safety when celebrating the 4th of July holiday over the next few days. 28 && .LONG TERM... (Tuesday morning through next Saturday) Issued at 309 PM EDT Sun Jul 2 2023 Key Messages: - Afternoon to evening thunderstorms possible on the 4th. Some could be strong to severe. - Heat will continue through the week, though not quite as warm as yesterday and today. - Thunderstorms possible most days in long term forecast. Summer in the south continues. 4th of July: No changes made to the extended periods. Shortwave trough over the northeast will continue to exit to the Atlantic going into the 4th, leaving behind a stalled frontal boundary to the north of the CWA. This along with remnant outflow boundaries from the previous evening will once again be a focus for more convection. I don`t want to rain on anybody`s parade, but numerous thunderstorms may actually bring some rain and thunderstorms to a few parades across the CWA. Some of these will certainly persist into the evening, so if organizing or going to any events to celebrate the 4th, please stay weather aware and remember that if thunder roars, go indoors. 2000+ J/kg of SBCAPE is noted during the afternoon across the GEFS members, so a few strong to severe storms will be possible, which is yet another reason to remain weather aware during any celebrations. Heat may also be a concern, as forecast heat index values are approaching 100- 105 across much of the CWA. However given that convection is expected, especially in north GA where there will be better proximity to the stalled boundary, this may limit impacts with cloud coverage and rainfall. Decisions on the need for any heat advisories will be made with future forecast packages, as uncertainty is a bit too high. Rest of Forecast: Through the midweek, pattern won`t change very much. Diurnally driven convection will be possible each day as copious moisture remains in the area. High temperatures are forecast to remain in the 90s, which when combined with the humidity, will keep heat indices up near 100 or higher. By end of week, strong trough digs into the midwest and helps drive frontal boundary towards and even into the CWA, though boundary will be quickly washing out as it approaches. Appears as though we will see more rounds of afternoon convection likely driven in part by this boundary. That said, GEFS members do have a bit of uncertainty in just how this will play out and what instability may look like. But, give me a boundary, even a weak one, approaching the CWA with relatively high PWATs in July, and I`m going to bet on the convection happening. Lusk/01 && .AVIATION... (00Z TAFS) Issued at 734 PM EDT Sun Jul 2 2023 TSRA is ongoing across portions of far northeast GA, with light SHRA trailing behind in the ATL metro. An additional cluster of TSRA is positioned moving into southwest Georgia, including over CSG at the time of this writing. As the storms are expected to move northeastward, the TEMPO for TSRA at ATL now runs until 00-03Z. Precipitation chances are expected to diminish after midnight. Some MVFR level clouds will be possible during the morning hours after 10Z. Another round of SHRA/TSRA will be possible after 18Z. Prevailing winds will be W to SW through the period at 4-8 kts, although stronger winds will be possible with any thunderstorm outflow winds. //ATL Confidence...00Z Update... Medium confidence on all elements. King && .PRELIMINARY POINT TEMPS/POPS... Athens 73 94 73 91 / 40 30 30 50 Atlanta 74 94 74 90 / 40 30 30 60 Blairsville 67 87 69 85 / 60 30 30 60 Cartersville 72 93 72 90 / 50 40 30 60 Columbus 75 96 76 94 / 40 30 20 50 Gainesville 72 91 73 89 / 50 30 30 50 Macon 75 97 75 94 / 30 30 20 50 Rome 72 93 73 91 / 60 40 30 60 Peachtree City 74 94 74 91 / 40 30 30 50 Vidalia 76 98 76 96 / 30 30 30 60 && .FFC WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM EDT this evening for GAZ001>005-011-012- 019>025-027-030>039-041>062-066>076-078>086-089>098-102>113. && $$ SHORT TERM...28 LONG TERM....01 AVIATION...King
Area Forecast Discussion
National Weather Service Glasgow MT
807 PM MDT Sun Jul 2 2023 .DISCUSSION... EVENING UPDATE (0200Z): Main change for this evening was to lower hourly wind a few knots across the board for the overnight period by using the GLAMP and HRRR since the NBM was a bit high compared to observations. This also allowed the Lake Wind Advisory to expire at the previously anticipated time. GAH AFTERNOON UPDATE (2030Z): No major changes to the forecast for today. Some increases in QPF were noted for the rain expected overnight tonight through Monday morning, mostly concentrated in the southeastern portions of northeast Montana. Outside of that, the forecast and narrative remain fairly well on track from this morning. Cliff MORNING DISCUSSION: There is exactly one more day of this ice cream melting weather before we finally get some relief and reasonable temps across the area. A dry cold front will push through the area this afternoon with isolated pop up showers and thunderstorms possible ahead of the front. Brief strong winds will be the main severe threat through the afternoon and evening, though nothing more than an isolated strong gust here or there is expected. As opposed to yesterday where the highest sustained winds stayed to the north and south of Fort Peck Lake, today`s highest winds look to be more broad-brushed across the entire CWA. This combined with the expected above normal boating traffic associated with the holiday weekend led me to issue a Lake Wind Advisory from 10 AM to 8 PM today. The good news is the highest sustained winds look to retreat north for tomorrow. So it is unlikely, as of now, that the advisory will need to be extended past today. Something to watch as a shortwave moves through Monday/Tuesday will be a return to northwesterly flow which looks to advect some wildfire smoke out of Alberta into northeastern Montana and North Dakota. Currently the HRRR and RAP smoke models both show a first minor wave of near-surface smoke reaching northeastern Montana early Monday morning. Another, more significant wave of smoke is then expected to arrive late Monday night into Tuesday morning. At this time, significant impacts to air quality are unlikely but it would not be out of the range of possibilities to dip into the moderate to unhealthy for sensitive groups range, particularly during the overnight hours. Looking towards the mid to late week, temps will start to warm back up again as the trough exits to the east. Weak embedded shortwaves look to keep the chance of afternoon pop up showers and thunderstorms alive through the weekend. -thor && .AVIATION... UPDATED: 2330Z EXPECTED FLIGHT CAT: VFR Discussion: Mostly dry conditions expected with increasing cloud coverage through the evening. Sporadic showers are possible but not likely (<50% chance) From 09 to 19Z when a cold front arrives and moves through the region during the morninbg hours. WIND: West to northwest at 10-20 kts in the early evening. Then calming to 10 kts or less out of the north the rest of tonight through Monday. Cliff/GAH && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ weather.gov/glasgow
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
637 PM CDT Sun Jul 2 2023 ...Aviation Update... .DISCUSSION...(This evening through Sunday) Issued at 511 PM CDT Sun Jul 2 2023 -- KEY MESSAGES FOR THE ENTIRE 7-DAY FORECAST: * In the more immediate term, there is the possibility for a few thunderstorms (perhaps briefly strong?) to clip into mainly our far western-southwestern coverage area (CWA) this evening and overnight. Not expecting these to be a "major deal", but considering our forecast was thunderstorm-free up until 24 hours ago need to "spread the word" a bit more than usual given the holiday weekend. * While MOST areas should have a storm-free stretch Mon daytime- mid afternoon Tues, BY FAR THE MAIN ISSUE in the entire 7-day forecast right now is the good chance for fairly widespread and vigorous storm development along a seasonably-strong cold front late Tues afternoon-overnight. While do not want to make TOO big of a deal out of the severe storm threat itself (this does not look like an "outbreak" situation, but instead the fairly typical hazards of scattered damaging wind/large hail/heavy rain threats associated with an SPC Slight Risk designation), the timing for Independence Day outdoor events could honestly not be much worse for much of particularly the northwest 2/3rds of our CWA (southeast areas currently carry the lowest pre-midnight chances). * Also regarding Independence Day: albeit of overall-lesser concern, but nonetheless a "new addition" to our Hazardous Weather Outlook (HWOGID), afternoon high temps have crept up a few degrees for Tues/Independence Day (actual highs 90s most areas with a 100 not out of the question southwest), which combined with moderate humidity levels will drive at least limited parts of the CWA to 100+ degree heat index values (but still safely below our official Heat Advisory criteria of 105+). * In the wake of Tuesday night`s thunderstorm issues, Wednesday will be a much cooler day (highs mainly 70s versus 90s), with breezy north winds and at least isolated scattered/ lingering showers and probably non-severe storms for some. * Beyond Wednesday, an overall at least slightly cooler-than- normal temperature regime looks to continue Thurs-Sun (highs 70s to mainly mid 80s at most). The forecast is also "littered" with a number of still-uncertain chances for showers/storms, as an overall-active weather pattern continues. -- MORE DETAILS/FURTHER INFO BUILDING UPON THE KEY MESSAGES ABOVE (including all further discussion of Tuesday daytime-Sunday): - General overview of the large-scale upper air/surface weather pattern and rain/thunderstorm chances (including bit more on the Tues-Wed storm threat): At least in the "big picture", the latest ECMWF/GFS solutions remain in pretty good agreement (particularly through Saturday). Breaking things down in basics chronologically: - 1) Tonight-Monday night: The majority of the CWA likely stays dry as we reside under fairly weak west-northwest flow. However, a weak disturbance will track southeast through the region, bringing at least limited thunderstorm chances to mainly our western-through-southern zones this evening into Monday daytime. - 2) Tuesday-Wednesday: Our flow aloft strengthens noticeably as the southern fringes of a fairly low amplitude shortwave trough (extending from a larger scale trough/low over Canada) tracks east from the Northern Rockies toward the Great Lakes. This system brings faster zonal (west-east) to our region as we reside along the southern fringes of the main forcing from this wave, and well to the north of predominant upper ridging over the Desert Southwest into TX. At the surface, this system drives through the seasonably-strong cold front Tuesday afternoon-evening, sparking the aforementioned severe storm risk and bringing in the much-cooler airmass for mid- late week. Briefly looking at severe storm parameters a bit closer for Tues afternoon-evening, again this does not look like an "off the charts" threat, but latest NAM?GFS generally suggest healthy instability/CAPE of 2500-3500 J/kg and decent (but not extreme) 0-6km wind shear of 30-40 KT. Although far too soon to talk fine details, latest 18Z NAMNest (which goes out through 06Z Tues night/Wed AM) suggests perhaps a few brief supercell structures, but storms tending to grow quickly upscale into clusters along the low-level front zone. ALthough there are some model differences on how quickly the front and resultant instability clears south of our CWA for Wednesday, latest NAM/GFS currently support any severe storm threat by Wed afternoon focusing at least slightly south- southeast of our CWA (could be close though, and timing is still a little iffy that far out). - 3) Thursday-Sunday: Although instability levels appear to remain relatively modest over our area, various/intermittent chances for rain/storms remain in the forecast as we reside under the path of several low- amplitude disturbances passing through west-northwest flow aloft, with flow enhanced in our area as we remain well north of the persistent upper ridge centered over the Desert Southwest/Southern Plains. Uncertainty grows by Sunday, as the latest ECMWF/GFS solutions diverge, with the ECMWF more aggressive on trying to drop another shortwave trough/surface cold front in from the north-northwest. -- SHORTER TERM DETAILS SOLELY FOCUSED ON THE NEXT 36 HOURS (through Mon night/early Tues AM): - CURRENT/RECENT WEATHER SCENE AS OF 430 PM: Today has been very much "as advertised": seasonably-warm (highs on track to top out 86-90 most places), plentiful sunshine (only spotty/shallow cumulus) and light winds mainly near-to-under 10 MPH, with direction honestly rather variable with a surface high pressure axis in the area. Just a great summer day for a holiday weekend! In the mid-upper levels, water vapor satellite and short term model data confirm fairly weak west-northwest flow aloft, as the upper low that brought our spotty strong storms/localized heavy rain yesterday has departed well east to the Chicago region, while just upstream a more subtle/weaker disturbance is tracking southeast through the NE Panhandle, and has recently sparked some spotty storms from western NE southward into northwest KS. - THIS EVENING-OVERNIGHT: Leaned pretty heavily on recent higher-res HRRR runs for our thunderstorm (PoPs) forecast. In the mid-upper levels, the aforementioned upper wave slightly to our west-northwest will slowly work southeast overnight, bringing some enhanced lift/forcing to mainly our western/southern CWA as it does so. While have a dry forecast CWA-wide through 00Z/7PM, thereafter have modest chances for thunderstorms entering the picture this evening-tonight for areas mainly west of a Kearney-Lexington- Osborne line, due to combo of activity to our west drifting into our CWA and also perhaps new development flaring up along a north- northwest to south-southeast oriented axis of mid level moisture advection. Although am not expecting a legit severe threat (largely owing to weak deep layer shear only around 20KT), probably cannot rule out a marginally-strong storm especially pre- midnight before mixed-layer CAPE drops more solidly under 1000 J/kg. In other departments, the combo of light-but-southerly winds and increasing cloud (especially west) will help to keep overnight low temps a good 4-8 degrees milder than last night, with most places aimed 63-66. - MONDAY DAYTIME: ALthough there is a little bit more model disparity than I would prefer to see at such a short time range, feel pretty confident that at least the vast majority of the CWA remains dry, as the very slow moving mid level wave (perhaps more of a mesoscale convective vortex/MCV) gradually shifts east-southeast across our sate line/KS zones area. Latest HRRR depicts only limited/weak thunderstorm potential during this day in our far south, and have introduced some slight storm chances to parts of our KS zones as a result. However, later shifts will have to make sure this wave doesn`t track a bit farther north and necessitate some storm chances into our far southern NE zones as well. Otherwise, look for temps to warmup another 3-5 degrees versus today, with highs between 90-94 most areas. Afternoon breezes will generally average 10-15 MPH from the south, so a little bit more wind than today. - MONDAY EVENING-OVERNIGHT: Odds strongly favor at least the vast majority of our CWA staying dry/storm-free, as we reside "in between" forcing form the aforementioned disturbance departing across eastern KS toward MO< and ahead of the leading edges of forcing associated with the stronger wave that will bring Tuesday`s severe storm threat. As a result, previously-advertised small thunderstorm chances in much of our central/northern CWA have been removed, but did leave a small area of "iffy" slight chances in our far north (mainly Valley/Greeley) area, based mainly on the earlier 12Z NAMNest run. These chances are pretty slim though for sure. Otherwise, the trend of warming temps continue, as steady south-southeast breezes around 10 MPH through the night will allow low temps to hold up generally 2-4 degrees warmer than tonight (most areas aimed 65-70). && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Tuesday) Issued at 633 PM CDT Sun Jul 2 2023 VFR conditions prevail at both terminals through the forecast period. Light and variable winds are expected this evening and into the overnight and early morning hours. A few clouds are expected to move through the region through the forecast period. There is a chance for a few thunderstorms overnight to the west of KEAR, however, they are not currently forecasted to make it to the terminal. KGRI is expected to stay dry through the forecast period. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ DISCUSSION...Pfannkuch AVIATION...Wekesser
Area Forecast Discussion
National Weather Service Gray ME
1155 PM EDT Sun Jul 2 2023 .SYNOPSIS... Yet another in a series of upper level disturbances will bring wet weather back to the local tonight and Monday. Areas of rain and embedded thunderstorms are expected during this period, with some of that rainfall heavy at times. Scattered morning showers over the holiday may become more likely during the afternoon hours. Warmer temperatures and slightly drier conditions can be expected during the mid to late week period before more wet weather returns over the weekend. && .NEAR TERM /THROUGH MONDAY/... 1155 PM Update... Just some minor tweaks to PoPs and QPF as the first wave of precipitation has exited eastern zones. The next wave is currently approaching SW NH with the incoming 00Z guidance suggesting periods of at least moderate rain will be likely across southern NH into coastal Maine while amounts do not warrant any changes to the Flood Watch. 1020 PM Update...Main focus of this update was to tweak PoPs and trim back QPF over the next few hours along the Mid Coast as recent runs of the HRRR have backed off significantly on moderate to heavy rain here. This is also confirmed by recent radar trends and rain gages as rainfall rates have generally stayed well below 0.25 inches per hour. Have also increased QPF slightly across southern NH for the next wave that will start to move in after midnight. There has been some run to run fluctuations with the track of this wave as it is associated with ongoing convection across PA and will track along a warm front that continues to sit south of the NH/MA border. There is potential portions of southern NH could see 1-2 inches with this late tonight through sunrise and this wave will also bring additional rain along coastal Maine. Some recent runs of the HRRR does bring some heavier bouts into southern NH while the 00Z NAMNest keeps the heaviest rain south in Mass. Have not made any changes to the ongoing Flood Watch in central Maine as there continues to be some uncertainty in where the heaviest rain will be with this second wave and confidence is not high enough to expand the Watch into southern NH. At this time an area of concern will be across SE NH with this second wave as this area saw upwards of 2 inches of rainfall earlier this afternoon, although there has been a break for a couple of hours now. ORIGINAL DISCUSSION... A short wave trough currently impinging on our area from the west will move across the forecast area this evening allow for rain, heavy at times at least early on. There will probably be a break for most zones except perhaps the coast as the back edge of the first batch moves on through. However, the next short wave trough or perhaps MCV one can see via regional radar mosaics over western PA and western NY as of 19z will move into the area around midnight or so. This may allow for another bout of heavy showers and possibly a thunderstorm as PWATS climb to around 2 inches. With this said, have issued a flash flood watch for the Midcoast of ME and portions of central ME as this is the region where we expect the high PWAT air mass to be juxtaposed with with at least weakly organized frontogenesis as low level trough develops near the coast. This should increase rainfall rates there this evening. In addition this is where flash flood guidance is relatively low. Toward sunrise, another batch of heavy showers will be possible after a few hour break. Therefore the flash flood watch goes through noon Monday. Did not have enough confidence to issue a watch elsewhere but the second short wave trough (MCV) tracking our way could allow for localized flash flooding later this evening into the wee hours of the morning on Monday if bands of convective rain or thunderstorms can become more organized. Fog may be less widespread tonight due to the rain, but it could become dense at times, especially during breaks in the precip. && .SHORT TERM /MONDAY NIGHT/... A short wave trough exits the forecast area from west to east during the morning hours on Monday bringing at least a period of (mostly) dry weather for several hours for most folks. Lowered PoPs a bit for Monday as it looks like the best forcing for heavy showers and thunderstorms will be just to the south and southwest of the forecast area. However, we do expect scattered activity, especially in the mountains. Chances for heavy rain and thunderstorms increase again Monday night as another short wave trough approaches from the west. && .LONG TERM /TUESDAY THROUGH SUNDAY/... One in a series of upper level troughs will cross the region on Tuesday. This disturbance unfortunately will feed off plenty of low and mid level moisture to trigger more shower and thunderstorm activity. Locally heavy rainfall is possible. The precipitation will mainly be over central and southern areas, however a couple passing showers are unfortunately possible at any given location. Morning fog will lift over interior regions, however coastal areas will lag with the increase in visibilities. This is depicted in the latest HREF visibility probabilities. Despite the cloud cover, it will be slight milder and continued humid. Afternoon highs will reach the 70s in most locations, however interior Maine and southern New Hampshire will top out in the lower 80s. The convection will diminish Tuesday night as areas of fog settle in. The upper level trough will be slow to exit the region Wednesday and Thursday as weak upper level ridging attempts to build into our region. There will still be a chance for mainly afternoon showers or thunderstorms, however most of the day at this point will be dry. Increasing sunshine will allow for warmer temperatures as well with widespread lower to mid 80s. A cold front will approach the region on Friday, set up the stage for potentially a showery weekend as it stalls in the region and low pressure gradually develops along it. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... Short Term...IFR or lower conditions are expected to develop tonight (especially cigs) at most terminals as a showery and very moist air mass remains in place. Improvement is foreseen on Monday as we dry out a bit with most terminals going VFR for several hours. IFR conditions are likely to return Monday evening and tonight as the next bout of showers arrives. Long Term...Some fog will lead to LIFR conditions to continue through Tuesday morning especially near the coast before ceilings begin to lift. However, another round of scattered showers and storms are expected by Tuesday afternoon, which will produce IFR restrictions should they pass over any terminals. Fog and low stratus are again possible Tuesday night, especially near the coast. Slightly drier conditions will enter the region Wednesday, thursday and possibly Friday. However instability may allow for a few scattered, mainly afternoon showers and thunderstorms. Expect low ceilings and visibilities however to possibly continue at night, especially near the coast. && .MARINE... Short Term...A few 25 kt gusts possible on the waters this evening, otherwise we expect conditions to remain below SCA levels for the bulk of tonight through Monday night. Showers and fog will continue to be present, however. Long Term...Winds will be relatively light and seas will remain diminished. However, there will be plenty of marine fog over the coastal waters reducing visibilities. && .HYDROLOGY... Areas of rain will continue to cross the region tonight, especially over southern and eastern areas. The steady rain will become showery overnight with an additional inch of rain or higher in some areas, mainly southern areas. So far, we have been able to handle this amount of QPF, but radar trends and surface observations will continue to require monitoring overnight. More showers and scattered thunderstorms can be expected on Monday (especially Monday night) which will once again require close monitoring. The approach of an upper level trough may allow for showers and thunderstorms to be likely over interior section during the holiday before slight drier air arrives late in the week. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Flood Watch through Monday morning for MEZ014-020>022-025>028. NH...None. MARINE...None. && $$ UPDATE...Schroeter NEAR TERM...Ekster SHORT TERM...Ekster LONG TERM...Cannon
Area Forecast Discussion
National Weather Service North Platte NE
642 PM CDT Sun Jul 2 2023 ...Aviation Update... .SYNOPSIS... Issued at 341 PM CDT Sun Jul 2 2023 Key Messages: - Weather conditions Tuesday afternoon, evening and Tuesday night could become favorable for severe weather. - Locally heavy rainfall which could lead to flooding in some areas is also possible Tuesday night. - SPC has included wrn Nebraska in a severe weather outlook Thursday. && .SHORT TERM...(This evening through Monday night) Issued at 341 PM CDT Sun Jul 2 2023 A weak upper level disturbance drifting south through wrn Nebraska is the basis for isolated to low-end scattered POPs this afternoon and this evening. These storms will form in weakly sheared environment, winds aloft are about 15-20kts at h500-300mb. MLCAPE is fairly high, around 1500J/KG, leading to a very high bulk Richardson number of 100 or greater. Thus, strong storms are possible but the risk of anything more than brief severe storms appears low. The models suggest a slow weakening this evening and even after midnight. The result of modest moisture transport and a strengthening of the low level jet to 20 to 25 kts. The next thunderstorm chance develops Monday night. This thunderstorm chance affects just northern Nebraska with the brunt of the storm activity expected to move east through SD, but there is a chance it will duck south into nrn Nebraska. This speculation is based on a strengthening low level jet to 30 to 40 kts. The NAMnest and FV3 show this happening while the ECM, GFS, NAM12 and RAP do not. POPs are limited to 30 percent for this reason and the forecast leans on the WPC suggested QPF for storm coverage. Winds aloft at h500mb increase to around 25kts Monday evening and MLCAPE is around 2000J/KG. If the storms move south into nrn Nebraska, severe weather is possible. For this forecast, the SPC has confined the severe weather threat to SD. .LONG TERM...(Tuesday through Sunday) Issued at 341 PM CDT Sun Jul 2 2023 The thunderstorm forecast Tuesday appears to be hinging on the location of a sfc cold front during the afternoon peak heating period...20z-23z. It is in this area where the heaviest rainfall is expected. Most models, including the ECM, now show the front across scntl Nebraska while the SREF shows the front farther west across swrn and ncntl Nebraska. Although the best QPF is expected along and ahead of the front, there is enough moisture transport and dynamics behind the front to produce significant rainfall. WPC suggested a blend of models, aka the NBM, for QPF and that suggests the best rainfall across cntl and nern Nebraska. If the front slows up across swrn Nebraska, the good rain could shift west. Winds aloft will become strong along and ahead of the front Tuesday increasing to 30kts at h500-300mb. MLCAPE in the NAM12 is 3000- 4000J/KG and the BRN along and just behind the front is prime at 25- 75. This would seem to suggest the potential for severe storms anchored on the front and isolated severe storms north and south of the front. If the storms become anchored, the 1.50 inches of PWAT and strong moisture transport would easily produce locally heavy rainfall. It will be interesting to see what happens. The CAMS are quick to fire late in the afternoon while the NAM12 waits for the dynamics firing storms after 00z Tuesday evening. There is little change in the extended forecast philosophy. A belt of 35-60+kt h500-300mb winds will descend upon wrn and ncntl Nebraska Tuesday and remain in place through Sunday. Any storms which develop during this time, could potentially become severe, provided sufficient CAPE is available. The NBM and SPC suggested Wednesday will be fairly quiet but severe storm development is possible across wrn Nebraska Thursday. Thunderstorm chances continue Friday through Sunday. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 641 PM CDT Sun Jul 2 2023 Near term guidance has been trending more favorable for thunderstorms that impact the KLBF terminal anytime through 06z this evening. If so, wind gusts to 35kts and visibility reduction to MVFR or lower would expected. Coverage still does not warrant a categorical mention, but will continue VCTS and update once confidence increases. Otherwise, western and north central Nebraska terminals will remain VFR through the TAF cycle, though winds spees pick up late in the forecast period at KVTN. Overall confidence is high, though low in convective development. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CDC SHORT TERM...CDC LONG TERM...CDC AVIATION...Jacobs
Area Forecast Discussion
National Weather Service Marquette MI
743 PM EDT Sun Jul 2 2023 .SHORT TERM...(Through Tonight) Issued at 301 PM EDT SUN JUL 2 2023 Water vapor imagery and RAP analysis show shortwave ridging extending from western WI across western Lake Superior to Hudson Bay with pronounced mid-level dry air noted over Upper MI. Thus, it`s been a dry day across the fcst area. Fog/stratus over eastern Upper MI early today burned off late morning, and now a considerable cu/stratocu field is noted inland from the stabilizing influence off of Lake Superior. Out on Lake Superior, fog and areas of dense fog persist, moving around with the changing near sfc winds. At 18z, temps across the fcst area are in the 70s F, but range down to the 50s/60s near Lake Superior. Once again, Copper Harbor is the cool spot at 52F. Out on the breakwater at Grand Marais, it`s 49F. A quiet night is expected tonight under sfc high pres ridging. With loss of daytime heating, the cu/stratocu will dissipate fairly quickly this evening, leaving behind a clear night. With the setup fairly similar to last night, expect fog development to be more widespread across the eastern fcst area overnight. Patchy, shallow fog will be possible elsewhere. Temps will fall back into the upper 40s to mid 50s F. Some of the traditional interior cold spots will slip into the mid 40s F. .LONG TERM...(Monday night through Sunday) Issued at 327 PM EDT SUN JUL 2 2023 By Monday morning, high pressure over Lake Superior weakens further with surface low pressures being centered over the Lower Great Lakes and Manitoba. Winds are still expected to be low enough that most hi-res guidance shows lake breezes off of the Great Lakes forming in the afternoon. There is some uncertainty in PM precipitation for the far west associated with an approaching dying boundary. Virtually all of the WRF models within the 12Z HREF show convection reaching Ironwood by 00Z Tuesday, but the HRRR, RAP, and last 2 NAM Nest runs show convection remaining further west entirely beyond the MI/WI state line. Ultimately, it seems like whatever convection does fire on the MI side of the line will be fairly short lived as the convection moves into an increasingly stable environment post-00Z. With the deterministic GFS showing 500mb ridging over the western UP at Tues 00Z, elected to go with only slight chances for precip Monday night in this forecast package, but it is a boom-or-bust forecast. The weakening high pressure means plenty of surface heating, so if storms do fire up or a remnant MCS reaches the UP, there is some potential for lightning, heavy downpours, and maybe some strong winds/light hail. Unsettled weather arrives early Independence Day as a trough (-12 dam anomaly per 12Z GEFS) advances through Manitoba and a shortwave on it`s southern periphery advances through MN. The Euro ensemble has trended upwards in precip totals to match the GEFS from yesterday. Rain is still expected to be higher over the west, with the 25th to 75th percentile range for QPF being a quarter to nearly a full inch of rain while the central UP ranges from a few hundredths to a quarter inch, and the eastern UP missing out nearly entirely. Chances of the showers (especially in the afternoon) becoming thunderstorms has increased with GEFS mean SBCAPE values up to 1200+ J/kg of CAPE and a few ensemble members much higher across the west half of the UP. With wind profiles veering and giving curved hodographs and plenty of instability, some storms may be strong to severe. Make sure your 4th of July plans include being weather-aware and continue to monitor the forecast as details are continuing to be refined. Additionally, it would be advisable to dress lightly as warm southwesterly flow aloft will help temperatures to climb to near 90 in the interior. The bulk of precipitation is expected to fall Wednesday as the cold front is draped south from the parent low lifting into the Hudson Bay. Deterministic and ensemble mean now show about an inch of QPF across the UP by Thursday morning, though some outlier solutions do show the potential for some areas to get nearly double of that amount. This should be a day-long light rain so flash flooding should not be a huge threat especially given the recent stretches of dry weather leading to more dry soils, but model trends may need to be monitored for the potential for some spots to get high rain rates. The vast majority of the rain will have vacated the UP vicinity early Thursday, and following the cold fropa, temperatures will be below normal. The end of the week looks to dry out as a surface high of around 1018mb per ensemble means advances over the Upper Great Lakes. Beyond the end of the work week, ensemble spread increases greatly, but mean 500mb height anomaly in the ensembles show a persistence of northwesterly to zonal flow with a fairly deep trough being over the Great Lakes by early next week. This hints at a continued active pattern of precipitation and slightly cooler temperatures than average. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 742 PM EDT SUN JUL 2 2023 VFR conditions will continue through the evening hours. The potential for fog development at all three TAF sites is the main challenge this forecast package. There is disagreement between several of the short range models on fog development overnight, with a few suggesting no fog, while others indicating fog development similar to what was experienced this morning. Key differences for tonight are that we are starting with slightly lower dewpoints this evening than yesterday, and the fog is not quite as expensive over Lake Superior. Add in that the area will see some high cloudiness moving in from the convection out west, and this may be enough to limit the impacts of the fog that does develop. It may be possible for some IFR visibilities overnight, but have only introduced MVFR visibilities at this time. Any fog that does develop will quickly burn off shortly after sunrise, and VFR conditions will prevail through the remainder of the forecast. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 327 PM EDT SUN JUL 2 2023 With weak pressure gradients for much of the CONUS and Canada east of the Rockies, winds will remain below 20 knots for the entire forecast period. The highest winds will be following a cold front on Wednesday into Thursday, where wind gusts may briefly exceed 20 knots in some areas of Lake Superior, especially on elevated platforms. With the lack of winds, the areas of dense fog over Lake Superior will persist through at least Monday morning. Some thunderstorms are possible over western Lake Superior Monday afternoon and over the entire lake Tuesday afternoon through late Wednesday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Dense Fog Advisory until 11 AM EDT /10 AM CDT/ Monday for LSZ162- 243-244-248>251-263>267. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...GS AVIATION...RJT MARINE...GS
Area Forecast Discussion
National Weather Service Morristown TN
920 PM EDT Sun Jul 2 2023 ...New SHORT TERM... .SHORT TERM... (Tonight through Monday) Issued at 907 PM EDT Sun Jul 2 2023 Radar is quiet across the area for now. Therefore, canceled the SVR watch that was set to expire at 9 PM EDT. Pockets of moderate instability remain across the area but lapse rates are poor, which doesn`t support strong updraft development. Stronger forcing exists to our west ahead of a cold front, where showers and storms are ongoing across west TN and up through central and eastern KY. We will be monitoring a line of showers and storms as they move through middle TN and approach our area over the next several hours. However, recent runs of the HRRR show this line weakening and falling apart as it enters our area. So overall, the severe threat the rest of the evening is very low but an isolated strong to severe storm can`t be ruled out as this line approaches the Cumberland Plateau. && .LONG TERM... (Monday night through next Sunday) Issued at 308 PM EDT Sun Jul 2 2023 Key Messages: 1. Showers and thunderstorms will be concentrated in the southern areas and eastern mountains Tuesday and Wednesday. This is near the weak frontal boundary that becomes stationary near the southern TN border Monday night. Overall should be less coverage than today. 2. Beginning Thursday the earlier front will have dissipated but a new weak front will move into the lower Ohio and lower Tennessee Valleys. More scattered showers and thunderstorms are expected to develop ahead of it late in the day Thursday. Storms should become most numerous late Friday and Friday night. 3. Behind front Saturday and Sunday more uncertainty with convection due to possible convection moving in from north or northwest with upper level disturbances. 4. Temperatures will generally be near seasonal normals for the period Tuesday through Friday. Slightly cooler Saturday and Sunday. Discussion: Next upper trough settles over the Great Lakes and Ohio Valley with a frontal boundary sagging over the southern Tennessee Valley Monday evening, somewhere near the border of TN and AL/GA with convection most likely ongoing at least for a few hours after 00Z on the 4th. A west to east flow will be seen Monday night through about Wednesday. Highest rain chances will be along the southern border and higher elevations both Tuesday and Wednesday. ECMWF shows the most convection with GFS and NAM model showing less activity those days. After the front dissipates there may be a brief break in convection Wednesday night into Thursday but a new frontal system approaching from the west will increase moisture and instability late Thursday through Friday night. Behind the next front Saturday and Sunday impulses in the upper flow will move south or southeast with more good chances for showers and thunderstorms. The Canadian, GFS and the ECMWF models all show MCS activity will be possible across the forecast area with strong to severe thunderstorms moving through Saturday night or Sunday, but it is too far in the extended to know for sure. Will have chance pops both days and likely in the higher eastern mountains. && .AVIATION... (00Z TAFS) Issued at 727 PM EDT Sun Jul 2 2023 Low confidence in the TAF forecast over the next several hours. A line of showers and storms is to our west, now moving into Middle TN. Models show this line weakening as it moves closer to our area. Therefore, no mention of VCTS or TSRA at any TAF sites. Will amend if the line holds together as it approaches. Otherwise, mostly VFR through the period except for some MVFR fog at TRI later tonight. More showers and storms possible tomorrow morning and early afternoon. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 72 90 72 90 / 50 60 40 60 Knoxville McGhee Tyson Airport, TN 71 88 71 88 / 70 40 20 40 Oak Ridge, TN 69 87 69 87 / 60 40 20 40 Tri Cities Airport, TN 68 86 68 85 / 60 40 20 30 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM... LONG TERM....TD AVIATION...
Area Forecast Discussion
National Weather Service Norman OK
1016 PM CDT Sun Jul 2 2023 ...New AVIATION... .UPDATE... Issued at 839 PM CDT Sun Jul 2 2023 Convection over the Texas panhandle is persisting more than the models would have led us to believe, therefore will be increasing POPs in the west. Think there will still be an eastern limit of how far these will go as stability decreases once we get too far east of the 100th meridian. But the RAP suggests a moist layer at about 750/800 mb in northwest Oklahoma where a lifted parcel would have little negative area to overcome, and thus these storms have some potential to persist into at least northwestern Oklahoma and perhaps farther south as well. Will continue to watch trends in the convection as it approaches. && .SHORT TERM... (This evening through Monday) Issued at 332 PM CDT Sun Jul 2 2023 The positively tilted trough, currently centered near northwest Nebraska, tracks southeastward and reaches north/central KS by tomorrow morning. The line of thunderstorms developing over eastern New Mexico and southeastern Colorado could eventually form an MCS over the panhandles this evening and into tonight. There is a chance that remnants of this activity could enter western Oklahoma late tonight but we will most likely see outflow move into western Oklahoma resulting in a wind shift. A weak quasi-stationary frontal boundary, currently draped across far southwest Oklahoma (near the Red River) towards southeastern Oklahoma is expected to remain in our area through the short term period. In fact, this boundary is forecast to gradually lift as a warm front through tomorrow night. Moderate instability, weak shear, and little to no CIN should provide an environment for scattered strong to marginally severe thunderstorms tomorrow afternoon from north-central to southeastern Oklahoma. Lightning, gusty winds, and small hail are possible with these storms. Higher- end PWAT values, with modeled values residing within the climatological 75th-90th percentiles, suggest efficient rain producing cells. Therefore, locally heavy rainfall is also possible. Thompson && .LONG TERM... (Monday night through next Saturday) Issued at 332 PM CDT Sun Jul 2 2023 Tuesday should be mostly dry and seasonably hot with highs in the mid/upper 90s. Temperatures are expected to rise to near the century mark over a part of northern OK and southwest OK and western north TX. There are a few models suggesting isolated storm activity over S/SE Oklahoma on Tuesday afternoon, but POPs remain mentionable for now. Guidance still points to a cold front moving into northern Oklahoma mid-week with POPs increasing late Wednesday and possibly into Thursday morning. WPC has issued a marginal risk of excessive rainfall for this activity, mainly for areas north of I-40. NBM has backed off a bit on cooler temperatures for Thursday and Friday due to the slower speed of the front with the older ECMWF model, though this may be short-lived. The 12Z ECMWF and GFS seem to be in somewhat better alignment with the front arriving late Wednesday and both deterministic models show moderate to heavy rainfall possible on Wednesday night. Shortwaves translating within the northern periphery of the ridge may lead to nocturnal MCS`s over the high plains Thursday and Friday nights, and therefore, chances increase across the northern half of Oklahoma for these periods. Excessive heat may be in issue next weekend with heat index values near or above 105 degrees. Thompson && .AVIATION... (06Z TAFS) Issued at 1016 PM CDT Sun Jul 2 2023 The convection is waning in the Texas panhandle except for some new storms kicked off by the outflow boundary. But those storms are already getting undercut. May still see some showers and storms in western Oklahoma, but the chances look too low to mention at KWWR, KCSM and KLAW. There will likely be some scattered showers and storms develop on Monday afternoon with the highest chances in central and north central Oklahoma. Except for the showers and storms, VFR conditions are expected. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 71 92 72 95 / 10 30 10 10 Hobart OK 70 94 71 97 / 20 20 10 0 Wichita Falls TX 72 99 73 100 / 10 10 10 0 Gage OK 66 93 68 98 / 40 20 10 0 Ponca City OK 68 92 68 96 / 10 30 30 10 Durant OK 73 96 73 95 / 20 20 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...01 LONG TERM....01 AVIATION...26
...Update to aviation forecast discussion...

.DISCUSSION... Issued at 233 PM CDT Sun Jul 2 2023 Key Points: -Slight rain chances tomorrow and Tuesday -Best shot of storms on Wednesday -Much cooler end of week Discussion: Clear skies and warm weather has dominated today, as our trough begins to pull away. Subsidence is noticeable on RAP analysis soundings, and the cumulus developing will remain fair weather. Clouds will increase tonight as our next system approaches from the west. Model consistency has not been good on this system, as it`s a fairly weak disturbance. The trend has been to move the 500 mb vort max to the North, so the chances of precipitation will be slightly higher, mainly across southwestern portions of the area. The 12Z HREF shows that there is some CAM support for thunderstorms, and the coverage for our area has increased since the 00Z run last night. The southwestern portion of the area has better upper level forcing, and looks like it will also have lower LCLs, making initiation more likely further South. These storms should continue to the east through the night on Monday into Tuesday morning, completely exiting by the morning. For Tuesday, the 4th, a trough with a strong jet streak aloft will move into the Northern Plains. As a cold front dives South through the Northern Rockies, the 250 mb jet should position itself so that the thermal gradient is underneath divergence aloft, which should help to spin up a low pressure. This will increase thermal advection, and cause our chances of precipitation to increase during the evening Tuesday. It seems that an MCS is probably going to form along the cold front in Nebraska, and move to the southeast towards northern Kansas. The most concerning scenario for outdoor events would be if thunderstorms form with the strong moisture advection taking place across central KS. We have not introduced mention of showers and storms Tuesday afternoon, but it is something we`re monitoring. The high resolution NAM has a moisture gradient that runs north-south through the middle of the CWA, which could trigger isolated storms. The main MCS could propagate through our area later on in the nighttime, though timing is uncertain. There is a Day 3 Slight Risk for areas generally N of I-70, with the main hazards being large hail and damaging winds, with large instability values but not-so-strong shear. Also worth noting is the heat for the afternoon on Tuesday - It looks like the heat indices area wide will approach or exceed 100 degrees, so people running outdoor events or celebrating the holiday need to be extra aware of that, especially from 2-8 PM. On Wednesday, the cold front will make more progress through the area, and widespread rain and thunderstorms are likely. There is a Day 4 Slight Risk for severe weather, but the details for that far out are not clear yet. Still, some thunderstorms could be strong. As mentioned in previous discussions, the summertime NW flow regime looks likely to set up through the end of the week into the weekend. Predictability is low with these setups, but frequent thunderstorm complexes could form on the lee side of the Rocky Mountains, and propagate along the `ring of fire` around the ridge. None of the days should be a washout, but scattered storms look likely for the long range forecast at this point in time. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 618 PM CDT Sun Jul 2 2023 Expect VFR conditions over the next 24 hours. light to calm winds through Monday morning will become southeasterly Monday afternoon and may increase to 5 to 10 KTS. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Teefey/Montgomery AVIATION...Gargan