Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/25/19

temperature are still on track. Remainder of forecast discussion
A surface trough currently over southern Ontario will drop south through the region overnight. Limited moisture and weak lift will result in only isolated snow showers. The only area which may see brief scattered coverage would be northern Oneida county and parts of the Finger Lakes region. Snow accumulations here could result in a dusting. Overnight lows will range in the lower to mid 20s across central New York and upper 20s to mid 30s across northeast Pennsylvania. Monday/Monday night...High pressure will build into the central Great Lakes as a low pressure system passes to our south into the mid Atlantic region. Skies will clear out quickly Monday morning behind the surface trough with clear skies for Monday night. In the far southeast high clouds may persist due to the system in the mid Atlantic region. A fairly cold airmass will be over the area with highs on Monday in the mid/upper 30s in central New York and upper 30s to lower 40s in northeast Pennsylvania. Lows Monday night will range from the teens to lower 20s. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Very quiet weather in the short term with a large area of high pressure at the surface building across the region keeping the area dry with gradually warming temperatures. Upper level cyclonic flow will be replaced by weak ridging aloft Tuesday and Wednesday...and when combined with much drier air and the presence of a strong surface high, the chances for precipitation will remain near zero. The surface high will shift off the New England coast Wednesday night as the next system prepares to move in across the upper Midwest and the Great Lakes. Cloud cover will begin to increase late Wed night, along with an up-tick in sw winds due to a strengthening sfc pressure gradient. Temperatures Tuesday will start off on the cool side...only into the mid and upper 30s during the day...and then drop into the teens and lower 20s under mostly clear skies Tue night. Conditions rebound on Wed into the upper 40s and lower 50s. && .LONG TERM /THURSDAY THROUGH SUNDAY/... A weak front will push in from the west Thursday with a minimal amt of rain expected during the day as the dry air will first need to be overcome. The front will lay out west-east across the region Thur night through Friday with scattered rain showers possible...especially across central NY. Winds will increase on Thursday out of the s/sw with sustained winds around 10 to 15 mph and gusts around 20 mph possible. The next system will move in from the sw...tracking from the Ohio Valley into the Northeast. There is still a good deal of uncertainty with respect to the track of the sfc low...which will be significant in determining precip amts and timing. For now just keep with a chance of rain showers into the weekend. Temperatures Thursday through Saturday will remain on the mild side with afternoon highs in the 50s and lower 60s, and overnight lows in the upper 30s and 40s. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... 730 pm update... Primarily VFR conditions expected for the next 24 hours at most taf sites. A cold front drops south through the region from 05z at SYR/RME to 09z at AVP. With and just behind the front will be enough low level moisture for MVFR clouds at ITH/BGM/ELM for a few hours between 7 and 12z. High confidence ITH/BGM and medium at ELM. ITH/BGM might fall to fuel alternate MVFR. Rapid clearing is expected from north to south from 09z to 15z. Southwest to west winds at 5 knots shifting to the northwest with the front. Monday northwest winds at 8 to 10 knots. Outlook... Monday night through Thursday night...VFR. Friday...Restrictions possible in rain showers. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...RRM NEAR TERM...MWG/RRM SHORT TERM...BJT LONG TERM...BJT AVIATION...TAC
Area Forecast Discussion
National Weather Service State College PA
1150 PM EDT Sun Mar 24 2019 .SYNOPSIS... An upper low over the Miss Valley will weaken as it pushes east and merges with a shortwave diving southeast across Pennsylvania Monday. Canadian high pressure and associated dry air mass will settle south across the area during midweek. A cold front is then likely to push southeast across the region next weekend. && .NEAR TERM /UNTIL 8 AM MONDAY MORNING/... Radar shows some scattered disorganized light echoes, so far no rain reaching the ground all the way back into Central OH. The HRRR keeps the precip disorganized and suggests the best chance for some small measure of rain will be over the SW and along the Mason Dixon line overnight. In general I trimmed back the already low POPs and QPF. && .SHORT TERM /8 AM MONDAY MORNING THROUGH MONDAY NIGHT/... A shortwave over the Midwest will get absorbed into the very fast WNW flow aloft, causing the surface wave to get squeezed mainly south of the forecast area. The HREF shows mainly light rain moving across the southern stripe of counties tomorrow afternoon into the early evening. Surface ridging and much drier air mass over upstate NY will build back in for Monday night. && .LONG TERM /TUESDAY THROUGH SUNDAY/... The axis and SWWD extend of an upper trough over southeastern Canada and deepening cold air will extend across PA Monday night. At the same time, the northern extent of light precip (from a weak sfc low and southern stream trough) will brush our southern zones and will transition into a light rain/snow mix for a short period prior to ending by 04Z Tuesday. No snow accum is expected as sfc temps will be in the mid to upper 30s. NW flow aloft and dry conditions with below normal temps will follow for Tuesday, with strongly anticyclonic flow/subsidence at llvls. The NW flow aloft will abate for midweek as a large area of sfc high pressure builds across the Commonwealth. Mainly clear skies are expected for later Monday night right through Wednesday. A slow-moving frontal boundary, draped to our northwest across the Grt Lks, may sink SE into the region Thu night or Friday before stalling out as a weak northern stream trough slides from the Upr Glakes to the Canadian Maritimes. A deepening upper trough and 1000 mb sfc low over the Central Plains and Mid Miss Valley respectively late Fri Night/Sat will lead to a quickly expanding rain/snow field from the Central Plains to Upper Glakes, with a building ridge along the East Coast keep us very mild and mainly dry under south-southwest flow at the sfc and aloft. Near to slightly above normal temps are forecast for Wed under the central of the high. Afterward, temps will rebound to 7-10F above normal Thursday, and peak at 15-18F above normal Friday and Saturday. Will maintain a chance of showers across northwest Pa late in the week through Saturday to account for model differences with regard to the exact location of the quasi-stationary/warm front that`s expected to stretch from Lake Erie NE across the St. Lawrence Valley. The greatest prob for rain showers comes for later Sat and Saturday night, when east coast ridge breaks down and a cold front pushes across the state. Above normal temperatures should hang on Sat before dropping back to near normal for Sunday with scattered rain/snow showers possible across the Mtns and isolated-sctd rain showers in the Valleys. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... VFR conditions continue to prevail across the region tonight. A cold front over central New York will slip southward through Pennsylvania during the overnight hours. A shift to northerly winds will accompany the frontal passage. While actual precipitation will be spotty overnight, increasing low level moisture and the upslope flow into the mountains will likely generate some MVFR ceilings. On Monday, a weak wave will ride eastward along the front, which should be south of Pennsylvania. Models generate limited moisture with this feature as is is sheared, but threat exists for some light precipitation and ceiling restrictions across the southern tier during the day. High pressure will then prevail through Thursday, with a frontal system approaching for Friday. .Outlook... Mon...AM rain/snow. Restrictions possible, mainly northern and western mountains. Tue-Thu...No sig wx expected. Fri.....VFR, but with some scattered showers possible northwest. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Fitzgerald/La Corte NEAR TERM...La Corte/Ceru SHORT TERM...Fitzgerald/Ceru LONG TERM...Fitzgerald/Lambert AVIATION...Jung
Area Forecast Discussion
National Weather Service Dodge City KS
1030 PM CDT Sun Mar 24 2019 ...UPDATE TO SYNOPSIS... .SYNOPSIS... Issued at 1023 PM CDT Sun Mar 24 2019 WV imagery indicates a zonal flow aloft prevailing across the Western High Plains. Near the surface, broad high pressure extends from the Northern Plains into the Upper Midwest. && .SHORT TERM...(This afternoon through Monday night) Issued at 1130 AM CDT Sun Mar 24 2019 Slow-moving upper low centered in SW IA at midday is still influencing SW KS weather, with stratus and stratocumulus still rotating into the northern zones. Updated sky grids to match this trend, but expecting some improvements this afternoon. Despite last night`s weak cold front and today`s modest northerly flow, temperatures should still manage to reach the lower 60s for many zones this afternoon. Northern zones where stratus is more persistent will remain in the 50s. A weak shortwave approaching in the NW flow aloft is expected to generate scattered high-based/weak convection across the Colorado Rockies and near the Raton Mesa this afternoon. 12z NAM and the latest HRRR iterations continue to show some of this convection reaching the western/SW zones this evening. Increased pop grids to the solid 50% chance category in the Elkhart vicinity, with some showers possibly surviving as far east as Liberal by midnight tonight. Moisture is scarce, as such much of the rainfall will be lost as virga. With dry subcloud layers, some gusty outflow winds may accompany some of this activity. Most of SW KS will remain dry tonight, with increasing mid layer clouds early, followed by increasing stratus through Monday morning. Lows Monday morning will be held above normal by the cloud cover, in the upper 30s and lower 40s. Monday will feature plenty of clouds, especially early, as the weak shortwave shears its way through. High pressure surface ridge over SW KS at sunrise Monday will hold firm much of the day, which will keep winds light NE or light and variable. Conversely, the cloud cover and this lack of mixing, coupled with minor cooling at 850 mb, will hold temperatures back Monday, with many locations holding in the 50s. 12z NAM MOS appears too cold with a high of 50 at Dodge City Monday, but if the expected morning stratus is stubborn, then the going forecast of mid to upper 50s would be several degrees too warm. .LONG TERM...(Tuesday through Sunday) Issued at 230 PM CDT Sun Mar 24 2019 Tuesday...Much windier and much warmer. Broad ridging builds over the plains aloft, with little cloud cover. Strong return flow is expected by afternoon, with strong south winds behind the large eastward retreating surface high. South winds of 20-30 mph will be common, with gusts near 40 mph. Afternoon max temps warm to the lower 60s east, to the lower 70s west. Wednesday...Still windy, and warmer still. Near zonal flow continues on top of broad ridging over the southern plains, for little cloud cover other than passing cirrus. Placed the strongest wind guidance available in the grids, with S/SW winds averaging 25-35 mph, with gusts near 45 mph. Models show a decided downslope component, which will propel temperatures to the mid 70s east, to near 80 west. Thursday...The warmest temperatures from this warming trend are expected across the southern counties. Thursday morning low temperatures will be abnormally warm, in the 50s, with mixing, increasing moisture and the LLJ. 12z MEX/GFS guidance is still quite warm Thursday afternoon, with lower 80s common, although 12z models introduce a weak prefrontal trough/boundary and associated wind shift that may relegate these warmest temperatures to near the Oklahoma border. At any rate, Thursday will be pleasant with well above normal temperatures, and much less wind as low pressure organizes nearby. Continued dry through daylight Thursday. Although models are waffling a bit on timing, a strong cold front will race through SW KS sometime during the Thursday night/Friday time frame. The models are in agreement tracking the synoptic trough far enough north, such as to keep the majority of precipitation north of SW KS during the Friday timeframe. Retained the pops offered by the model blend for Friday for mainly scattered rain showers, out of respect for dynamic lift and frontal convergence. Much colder air will arrive Friday and Saturday, with afternoon temperatures struggling to reach 50, with morning low temperatures Saturday returning to near freezing. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 536 PM CDT Sun Mar 24 2019 Under weak flow in the low levels and under an induced upper level ridge, fair weather cumulus will continue the rest of the evening with scattered to broken clouds around the 3-4kft level. Winds are mostly out of the north 10-12kts under a weak gradient expecting to diminish to light and variable after 09Z through the rest of the period as high pressure is the main influence during this time. With decent enough instability, weak air mass thunderstorms will push out of eastern Colorado this evening but should not make it as far east as GCK and LBL but something to keep an eye on for amendments. Other than that, low level stratus will invade the CWA affecting all sites by 09Z and possible MVFR ceilings after 12Z through mid morning. Stratus will lift and scatter out at this point due to daytime heating and weak mixing of the boundary layer winds to the surface. && .PRELIMINARY POINT TEMPS/POPS... DDC 39 58 38 66 / 10 10 0 0 GCK 37 58 39 67 / 20 20 0 0 EHA 39 61 40 70 / 40 10 0 0 LBL 39 61 40 70 / 20 10 0 0 HYS 39 55 37 65 / 10 10 0 0 P28 41 58 39 64 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JJohnson SHORT TERM...Turner LONG TERM...Turner AVIATION...Lowe
Area Forecast Discussion...UPDATED
National Weather Service Glasgow MT
742 PM MDT Sun Mar 24 2019 .DISCUSSION... Sent an update this evening to fine tune the location and timing of the wintry mix. Expect most of the change over from rain to snow thus far has been west of Highway 24. As the night wears on, will probably see more of a widespread change over to snow, but as it does, the storm system will become more disorganized. Freezing temperatures overnight will likely lead to slippery surfaces from the cold wetting rains from earlier today. Given the lingering threat as these scattered showers moves back eastward overnight, felt it was best to leave the Winter Weather Advisory in place for the combination threat of snow and freezing rain overnight tonight. BMickelson Previous discussion: Forecast challenge this package is on the ongoing precipitation. Tonight/tomorrow... So far today, we`ve had reports of mixed precipitation in Plentywood, and freezing rain in Roosevelt County (a CoCoRaHS report forwarded to us), and in Glasgow, with other areas of rain changing to snow. Decided to keep the winter weather advisory up for a few reasons: 1) precipitation is still ongoing; 2) icing events are a fairly rare event in the CWA, and we`ve already had icing and will continue to get it; 3) the wintry precipitation will stress newborn livestock in the area. So, it boils down to being an impact-based advisory because we are already being impact and will continue to be. All that being said, precipitation type will bounce around tonight across the area. The main area of precipitation shifted westward from before, so increased POPs generally west of Highway 24 and lowered them east of 24. Leaned a little more on the HRRR and RAP with making the adjustments tonight, which were more in line with reality initially, but still further east than the global models. The regional and high resolution models want to end the precip altogether tonight, while the global models keep things going through the night. Fog is also a possibility in the area tonight, and will need to be monitored especially for the southern zones. Precipitation should end from west to east tomorrow, with temperatures warming back up into the 40s. Tomorrow night and beyond... The upper level ridge begins to flatten out a bit Tuesday into Wednesday. Tuesday should be the warmest day of the week ahead, with areas south of the Missouri River easily going into the 60s. The next chance of precipitation begins to move into our southern zones Wednesday night as an upper level trough moves into the Pacific Northwest and the ridge pulls away. Precipitation chances will spread area-wide by Thursday, tapering off Friday. Temperatures fall back off late week as well as a result of the change in pattern. Avery && .AVIATION... FLIGHT CAT: A range of IFR to near LIFR expected tonight, improving to at least MVFR by tomorrow afternoon. DISCUSSION: A wintry mix of precipitation and associated low ceilings and reduced visibilities will affect area terminals across the region tonight through early tomorrow morning. Ceilings may remain low tomorrow afternoon due to the moisture from snowmelt and new precipitation. KGDV and KSDY will need to be monitored for fog potential tonight, and may require TAF amendments. WINDS: East at 10 to 20 kts, diminishing to around 10 kts early Monday morning. Winds shift to the southeast 10 to 15 kts by Monday afternoon. Avery/BMickelson && .HYDROLOGY... Creeks and streams across NE Montana are flowing high, with near bankful to out of bank conditions, adding to larger rivers downstream with levels rising for many locations along the Milk River, Yellowstone River, and the Missouri River East of Fort Peck. Decent snowpack yet remains to melt across Valley, Phillips, Daniels, and western Roosevelt counties. Flooding is already occuring over parts of this area and will continue into next week. Occasional ice jams have been reported along portions of the Milk and Yellowstone Rivers leading to areas of flooding. Sections of ice, both flowing and jamming continue to cause sudden rises and falls for many locations. Updated forecasts for areas near Tampico and Glasgow along the Milk River in Valley County show flood stages reaching and remaining near Major Flood Stage levels throughout this week. Today`s and tonight`s precipitation may briefly add to these rises. The current storm system will dissipate and move east of the region later on Monday. To monitor river stage readings, go to our Advanced Hydrologic Prediction Service (AHPS) page at then click on "Rivers and Lakes" then "River Observations". Data for this page are provided by the USGS. && .GLASGOW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 AM MDT Monday for Central and Southeast Phillips...Central and Southern Valley...Northern Phillips...Northern Valley. Winter Weather Advisory until noon MDT Monday for Daniels... Eastern Roosevelt...Sheridan...Western Roosevelt. && $$
Area Forecast Discussion
National Weather Service San Francisco Bay Area
902 PM PDT Sun Mar 24 2019 .SYNOPSIS...A Pacific storm system will spread moderate rain across the North Bay late tonight and Monday morning, with light rain then expected to develop south across much of the rest of the area on Monday afternoon and evening. Periods of rain are then likely to continue from Monday night through Thursday, with the most widespread rainfall expected late Tuesday night into Wednesday. Dry weather is forecast to return late in the week and into next weekend. && .DISCUSSION...As of 9:00 PM PDT Sunday...Evening IR satellite imagery shows a large upper low centered about 800 miles off the coast of the Pacific Northwest. To the south and east of this low center is the initial frontal boundary that is currently approaching the northern California coast. Models forecast light warm advection rainfall to develop out ahead of the frontal boundary and into the North Bay by around midnight tonight, and the KMUX radar is already showing weak returns near northwest Sonoma County. Latest HRRR and the 00Z NAM indicate that rain rates will increase in the North Bay late tonight as the frontal boundary approaches our coast. Moderate to locally heavy rainfall can be expected in the North Bay from late tonight through the Monday morning commute. The latest HRRR also forecasts moderate rainfall rates developing as far south and east as the San Francisco Peninsula and western Alameda County by midday tomorrow. The frontal boundary is then forecast to weaken significantly as it pushes south into the south Bay and Monterey Bay Area on Monday afternoon and evening. Rainfall totals in the North Bay through Monday evening are forecast to range from 0.5-1.5 inches with as much as 2 inches possible in northwest Sonoma County. Rain totals through late Monday for the remainder of our area are expected to be a quarter inch or less except up to a half inch along the SF Peninsula, and locally in the Santa Cruz Mountains and East Bay Hills. The weakened frontal boundary is forecast to stall along a line from about San Jose to Monterey late Monday night and persist there through Tuesday. During this time frame, scattered showers will be most likely near the stalled frontal boundary, but could occur most anywhere in our area. In any case, rainfall amounts from late Monday night through Tuesday evening are expected to be light. The upper low will finally begin to approach the far northern California coast late Tuesday night. A vigorous shortwave trough rotating around the low is expected to bring another round of widespread rainfall to our area from late Tuesday night through Wednesday morning. Scattered showers will continue into Wednesday afternoon and evening. In addition, the airmass will become increasing unstable late Tuesday night and Wednesday morning as the upper low approaches and we could see isolated thunderstorms on Wednesday. The upper low will be very slow to move to the northeast and out of our area, so scattered showers may continue through Wednesday night and into Thursday, primarily across the northern portion of our area. Additional rainfall from Tuesday through Thursday is forecast to range from 0.50-1.50" in most areas, with as little as 0.25" in our far southern valleys and as much as 2 inches in northwest Sonoma County. Forecast rainfall from late tonight through Thursday will mostly be beneficial, although some minor nuisance flooding is possible in the North Bay, particularly on Monday morning. Gusty winds can be expected at times through midweek. South winds may gust as high as 35 mph along the coast of the SF Bay Area from late tonight through early Monday afternoon. More widespread gusty winds are then likely from late Tuesday through Wednesday when southwest winds may gust up to 40 mph at the coast and in the hills. Southerly flow ahead of this system will result in mild temperatures through early Wednesday, with cooling then expected late Wednesday into Thursday. A forecast update earlier this evening included increasing temperatures, particularly at night, from Monday night through Tuesday night. Longer range models indicate dry conditions will return by Friday and continue into the weekend, although rain may develop in the North Bay by Sunday afternoon. && .AVIATION...As of 5:40 PM PDT Sunday...VFR extending through the evening with southerly wind flow, drying lower levels; the WRF model`s boundary layer and surface humidities initialized well except RHs are over-forecast along the Monterey county coast. High pressure moving to the Central Coast is setting up a SMX-SFO pressure gradient, currently 1.1 mb, and the SFO-ACV gradient is 1.6 mb. An eastern Pacific trough will bring lowering ceilings, mainly to the Bay Area, on Monday. Forecast is MVFR ceilings in light to moderate rain preceding an incoming cold front, post frontal wind shifts over to SW-W direction Monday. IFR ceilings and visibilities in rain over the North Bay mainly Monday morning. Light rain with a slow moving cold front eventually arrives along the north Central Coast Monday evening. Vicinity of KSFO...VFR, wind briefly onshore and mainly light becoming SE early to mid evening. Tempo light rain 11z-15z Monday with gradually lowering ceilings becoming MVFR in light rain by 15z. SE wind Monday shifting to westerly by late afternoon with cold frontal passage, wind gusty to 20-25 knots near late afternoon frontal passage and wind gusts lingering into the early evening. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR, wind onshore until mid evening then becoming E-SE with SE wind increasing in the Salinas Valley Monday morning and afternoon prior to cold frontal passage. Light rain developing 21z-22z and lasting into the evening. && .MARINE...As of 8:44 PM PDT Sunday...Winds southerly and rain developing through Monday morning ahead of approaching low pressure system and cold front. Gusty winds can be expected ahead of the front. Showers linger Monday night and Tuesday. Rain develops again during the mid-week then dry weather returns late week. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tngt...SCA...Pt Reyes to Pigeon Pt 0-10 nm from 3 AM SCA...Pigeon Pt to Pt Pinos 0-10 nm from 3 AM SCA...Pt Arena to Pigeon Pt 10-60 nm SCA...Pt Arena to Pt Reyes 0-10 nm from 9 PM SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm from 9 PM && $$ PUBLIC FORECAST: Dykema AVIATION: Canepa MARINE: Canepa Visit us at Follow us on Facebook, Twitter, and YouTube at:
Area Forecast Discussion
National Weather Service Blacksburg VA
1158 PM EDT Sun Mar 24 2019 .SYNOPSIS... High pressure slides off the North Carolina coast tonight. A front crosses the area Monday. High pressure builds back in for Tuesday and Wednesday. && .NEAR TERM /THROUGH MONDAY/... As of 1155 PM EDT Sunday... Temperatures still running a bit warmer in most areas that originally advertised. Thus, made some minor adjustments to the T and Td readings. No other changes needed at this time. As of 755 PM EDT Sunday... Just some minor changes to update the temperature and dewpoint grids. Temperatures a running a bit warmer than anticipated at this hour and dewpoints are running a bit lower. Warm dry air mass continues into the evening. So, slowed the cooling and moistening a bit based on latest HRRR and GLAMP25. Pops coming in tomorrow morning look good with isolated thunder in the afternoon south and Piedmont. As of 239 PM EDT Sunday... High pressure will slide east tonight and push into the Atlantic ocean. Meanwhile, low pressure in Missouri with a warm front extending east and a cold front trailing south will travel eastward tonight into Monday. For tonight, the warm frontal precipitation will lift north across the Ohio Valley with some spillover of rain showers toward central West Virginia. Clouds will increase tonight as the cold front approaches from the west. Isolated to scattered showers may reach into the western mountains by dawn. Played pops close to NAM for tonight. Low temperatures tonight will be milder with readings from around 40 degrees in the mountains to the upper 40s in the piedmont. A shortwave trough will spread southeastward over the Tennessee Valley toward the Carolinas on Monday. The cold front will move east across our region Monday. Scattered showers and a few thunderstorms will develop ahead and along the frontal boundary. Southwest flow ahead of the front will advect warm moisture air into our region. There is some weak convective instability from 18z-00z across southern portions of our forecast area. The Day Two Convective outlook places southern half of CWA in general thunderstorms. However, there is a chance for some graupel or small hail in stronger cells based on low wet-bulb zero heights. High temperatures Monday will range from around 50 degrees in the northwest mountains in western Greenbrier to around 70 degrees in the piedmont. Forecast confidence is high. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... As of 215 PM EDT Sunday... Surface low along with its associated cold front will shift slowly off to the southeast Monday night bringing the majority of the significant precip to an end. However as the upper trough consolidates over the area and the boundary layer flow turns more northeast, may see low level moisture get trapped beneath the subsidence inversion aloft later Monday night into early Tuesday espcly west. This as strong wedging starts to develop ahead of cold high pressure heading east out of the Great Lakes through midweek. Depth of the moisture and subsequent precip potential remains iffy since the Nam likely overdone and the GFS too dry per the surface high building in faster. Does appear better focus will be across the west/southwest while more north/northeast flow likely to limit to more of a cloud/drizzle/flurry scenario. Thus trimmed back going chance pops to mainly the west Monday night with a faster exodus of moisture Tuesday from north to south. High pressure and better drying to take shape Tuesday afternoon into Wednesday night as the high shifts offshore while still maintaining some wedging. This supports mainly sunny/clear skies for midweek but still cool given the low level wedge and 850 mb cold pool in place under northeast flow. Highs mostly 40s and 50s with lows 20s/30s each night. && .LONG TERM /THURSDAY THROUGH SUNDAY/... As of 130 PM EDT Sunday... Wedge of cool air across the region will gradually break down as the parent surface high slides offshore on Thursday allowing deepening warm advection to take shape ahead of another cold front arriving over the weekend. This in conjunction with sunshine under strong ridging/warming aloft per 850 mb temps climbing to +10 deg/C or higher should bring a quick moderation to above normal temperatures espcly from Friday onward. Timing of arrival of moisture with the weak upstream cold front remains uncertain given the strong ridge aloft over the southeast and best support with the front passing well north. Guidance suggests that pieces of shortwave energy may scoot east ahead of the boundary perhaps resulting in showers mainly mountains Saturday into Saturday night and elsewhere on Sunday. However solutions remain at odds with the GFS hanging the front up to the west through Day7, while the ECMWF/CMC keep things mostly dry with a more pronounced frontal passage Sunday including more showers. Since the GFS appears overdone with added energy off to the west will lean closer to the Euro and subsequent WPC solutions in having a cleaner fropa into Sunday. Highs mostly 50s/low 60s Thursday, warming to 60s and a few 70s east from Friday through Sunday including lows mainly in the 40s. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... As of 755 PM EDT Sunday... VFR conditions expected to continue across the forecast area until Monday afternoon as upper-level disturbance and cold front advance into the region from the west. BKN-OVC ceilings expected overnight, but all high-mid clouds mostly at or above 10kft to 15kft. Ceilings will lower into the MVFR and eventually IFR range late Monday afternoon into the evening as rain showers overspread the region and saturate the lower atmosphere from its very dry current condition. Visibilities will also remain VFR and mostly P6SM until the rain showers arrive mid to late afternoon Monday, then trend toward periods of MVFR in -SHRA BR. Winds will decrease a bit this evening to SW 4-8kts overnight with isolated low end gusts at times. Winds will become more WSW through the day Wednesday at 5-8kts then shift to the WNW and increase to 7-10kts during the late afternoon/evening coincident with the showers/frontal passage. An isolated thunderstorm is possible in the Danville area during the afternoon, so included VCTS there. Otherwise, did not mention TSRA at the TAF sites at this time, with little threat of any thunder west of the Blue Ridge. /Confidence in Forecast Parameters/ Ceilings - Moderate to High, Visibilities - Moderate to High, Winds - Moderate to High, Thunderstorm Threat Monday Afternoon - Low. EXTENDED AVIATION DISCUSSION... Sub-VFR conditions will continue into early Tuesday behind the front, mainly across the western mountains. W-NW winds may be a bit strong and gusty Tuesday, but do not appear to rival recent wind events. Dry weather on tap for Wednesday into Friday. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...KK/WP NEAR TERM...KK/RAB SHORT TERM...JH LONG TERM...JH AVIATION...KK/RAB
Area Forecast Discussion
National Weather Service Springfield MO
607 PM CDT Sun Mar 24 2019 .MESOSCALE DISCUSSION... Issued at 558 PM CDT Sun Mar 24 2019 Strong to severe convection continues ahead of the surface front in south central MO, as of 6 pm from near Shell Knob to Rolla. Areas to the south of the convection still in favorable area for future convection as air mass has not been modified yet. Large hail would be the primary severe weather concern. Convection should start to diminish after sunset with loss of daytime heating and diminishing instability. Hail up to 2 inches in size will be possible with the stronger storms. && .SHORT TERM...(This evening through Monday) Issued at 205 PM CDT Sun Mar 24 2019 Update: 18z KSGF sounding indicated a weak cap, but radar and satellite imagery increasing shows evidence of weakening inhibition with a small uptick in convective towers and isolated radar returns. This is in line with recent HRRR guidance. In general HRRR trends have been indicating a slightly later onset time of more widespread convection versus runs from this morning, however, the eastern cwfa should see scattered convection. Shear/instability profiles (nearly 1000 j/kg mlcape and 50kts 0-6km bulk shear) are supportive of supercells with large hail the main concern. A localized wind risk is also possible. A veered low level wind profile should limit the overall tornado threat The front is expected to shift east of the area this evening, so expecting a a brief window for severe storms in our area. After some brief clearing, low clouds should moves south on the backside of the system with some drizzle expected late tonight and Monday morning, especially in the northeast quarter of the cwfa. Cloud will likely hold on into Monday night as well .LONG TERM...(Tuesday through Sunday) Issued at 205 PM CDT Sun Mar 24 2019 Tuesday: A ridge of high pressure will nose south form the Midwest with finally some clearing expected Tuesday with seasonable temperatures. Wednesday: South winds will become gusty with warm weather as the sfc high moves off and a large upper ridge builds over the central CONUS. Thursday-Friday-Saturday: The upper ridge flattens out and shifts east as the southern branch of an upper level split flow pattern becomes the main player in our weather. Moisture will spread north in the persistent strong south low level flow on Thursday. By late in the weak the surface pattern becomes more active with a wave of low pressure likely to move through supported by a shortwave moving through the central Rockies into the Plains. Decent agreement with ECMWF and GFS in moving a sfc low through eastern KS and MO with a trailing cold front Fri night. Sunday: Guidance differs by this time on how far south the front will get. The GFS is more active with another sfc wave moving through the southern CONUS while the ECMWF is dry. Forecast reflects a blend of guidance. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 558 PM CDT Sun Mar 24 2019 Convection was located southeast of SGF/JLN, but will still be possible at BBG for the first couple/few hours of the 00z TAFS. Clearing should take place behind the convection, but will see stratus deck move in after midnight with MVFR and IFR ceilings possible through much of the remainder of the period. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ MESOSCALE...Lindenberg SHORT TERM...DSA LONG TERM...DSA AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Shreveport LA
1025 PM CDT Sun Mar 24 2019 .SHORT TERM.../Tonight/ The sct convection that did affect portions of McCurtain County OK earlier this evening have diminished/remained just N of this area and the adjacent counties in SW AR, as the convection has outran the greater axis of instability along the cold front, which extends from near FSM, to just S of MLC, AQR, SW to the Nrn and Wrn sections of the DFW Metroplex, to near SEP. However, additional sct convection has recently redeveloped near and just ahead of the front over portions of N TX, in the area of better instability where MLCapes near or slightly better than 1000 J/kg exist ahead of a shortwave trough noted over Srn OK and N TX. The short term progs have done a poor job with the handling of the ongoing convection, with the latest 00Z NAM much drier/less bullish with convection development through the remainder of the evening (especially near and N of DFW), but does suggest convection building ESE into more of E TX/extreme Nrn LA after 06Z. The latest run of the HRRR has initialized too far E with the ongoing convection and also does not take into account the convection N of DFW, but does suggest clusters of convection which should track SE across E TX into N LA overnight. Although some instability will persist overnight with additional low level moistening, the short term progs suggest that overall CAPE will continue to slowly diminish overnight, but with 500-800+ J/kg remaining over portions of E TX before the shortwave shifts E into slightly more stable air farther E into Scntrl AR/Ncntrl LA. Although an isolated severe threat may persist beyond the 05Z SVR Watch #33 expiration, did remove SVR mention after midnight, and did lower pops to likely across much of E TX/SW AR/N LA. But in the meantime, did add Smith and Gregg Counties in E TX to the existing SVR Watch #33 to account for extrapolation of the isolated severe warned supercell now entering Western Wood County. Also made very minor adjustments to the min temp forecast, with this convection diminishing from NW to SE late as H850-700 winds veer more WNW late. Zone update already out...grids will be available shortly. 15 && .PREV DISCUSSION... /issued 750 PM CDT Sun Mar 24 2019/ AVIATION... For the ArkLaTex terminals. No major changes to going TAFs with as KTXK only tempo group this cycle. All other sites will see this line of TS move from N to S from 06-12Z. Large hail and some wind will be wide spread until dawn. Fropa 12-18Z with SKC looming terminals becoming NW 10-20KT all day Monday./24/ PREV DISCUSSION... /issued 536 PM CDT Sun Mar 24 2019/ UPDATE... Zone update just sent for the issuance of SVR Watch #33 until 05Z for much of NE TX/SW AR/SE OK. Already seeing isolated supercell storms developing attm across portions of N TX/Ern OK, along a cold front that continues to slowly progress SE across these areas. SBCapes have risen to 1500-2000 J/KG along a narrow instability axis along/ahead of the front, with MLCapes expected to gradually increase this evening across the expanding warm sector over E TX/N LA/SW AR as a shortwave trough, analyzed over the Lower TX Panhandle and Wrn OK, continues to progress along and N of the Red River Valley through the evening and into Cntrl/Srn AR/N LA overnight. While isolated supercells with large hail are expected initially given the bulk shear of 50kts, some clustering of the convection is expected later this evening which will lead to more of a svr wind/hail threat, as they eventually shift SE into NE TX/SW AR late this evening, to near the I-20 corridor of E TX/N LA between 07-10Z. Did not make any additional adjustments attm to the going forecast. 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 61 77 49 67 / 60 60 0 0 MLU 61 77 49 66 / 60 60 0 0 DEQ 52 68 44 67 / 70 10 0 0 TXK 57 71 46 65 / 60 10 0 0 ELD 58 74 46 66 / 60 30 0 0 TYR 60 74 47 69 / 60 60 0 0 GGG 60 75 48 68 / 60 60 0 0 LFK 64 80 49 71 / 30 40 10 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 15
Area Forecast Discussion
National Weather Service Tulsa OK
735 PM CDT Sun Mar 24 2019 .DISCUSSION... Severe event is ongoing, and has played out much like the HRRR has been suggesting. A pair of supercells developed to the southwest of FSM and are moving east southeast with the Bunkers right moving supercell vector. Have had baseball size hail reported with one of the supercells. With the straight line hodograph wind profile, there have been several left movers, some of which could also extend the severe threat some over far SE OK longer into the evening. Portions of the watch have been cleared behind the convection, and more of it will be cleared in the next hour or so. Current PoPs trends are in great shape, and no changes are planned attm. Lacy && .PREV DISCUSSION... /Issued 410 PM CDT Sun Mar 24 2019/ DISCUSSION... At mid afternoon...the upper low was positioned across Northern Missouri/Southern Iowa with the cold front extending southwestward through Southwest Missouri into Northeast Oklahoma along a line from near Grove to Okemah and finally into South Central Oklahoma and Western Texas. Latest meso analysis indicated the cap continuing to weaken with a surface instability axis centered along and just east of the cold front. In response...radar echoes have begun to develop along the front across East Central Oklahoma...moving eastward toward Northwest Arkansas. Into the evening hours...the cold front is expected to continue to slide east southeast through Southeast Oklahoma and Western Arkansas as the upper low begins to trek more southeast toward the Ohio River Valley. The surface instability axis is forecast to be maximized across Southeast Oklahoma...where surface dewpoints in the low 60s currently resided. the cap continues to erode into the early evening hours...thunderstorms are forecast to continue to develop along the frontal boundary mainly across Southeast Oklahoma into Northwest Arkansas with the potential to become strong to severe. 40-50KT of deep layer shear combined with steep mid level lapse rates will allow for the potential for large hail and also damaging winds to be the main threats with this activity. 0-1km shear values continue to look fairly weak which should limit over all tornado potentials...though the threat is not zero. The greater severe potential looks to be generally along and east of a line from near Antlers to near Fort Smith where the surface instability max was located. Current indications are that by mid evening...03z...the cap should begin strengthening over the region as the cold front is forecast to be nearly exiting the CWA to the south and east. The result is the greater thunderstorm potential should shift south and east of the CWA with any remaining thunderstorms exiting the CWA by 06z. Between the 03-06z range...a decreasing strong/severe potential will remain possible though much more limited than earlier in the evening. Behind the cold front...drier air and northerly winds will spread southward over the region tonight as well as cloud cover associated with the backside of the upper low. These conditions will help to keep temperatures from bottoming out with lows in the 40s forecast for most locations over the CWA. During the day Monday...this cloud cover looks to remain over mainly Northeast Oklahoma and Northwest Arkansas until another quick moving shortwave within upper level northwesterly flow pushes through the region Monday night/Tuesday. Behind this shortwave...a ridge of high pressure is progged to push through the Plains with a return of southerly winds and a warming trend Wednesday and Thursday. Southerly winds increase Wednesday and become gusty Thursday ahead of the next forecast low pressure looking to move into the region. Gusts 25-35 mph and temps back in the upper 60s/lower 70s will help to increase fire weather dangers for the CWA before moisture returns with the approaching low pressure system Friday. Latest extended model solutions differ on the timing of this next system and its associated cold front. Thus...for this forecast...have continued with a blended approach with shower and thunderstorm chances becoming possible Thursday and increasing Friday into Saturday as the system moves through. && .PRELIMINARY POINT TEMPS/POPS... TUL 45 60 40 65 / 0 10 0 0 FSM 48 64 42 65 / 50 10 0 0 MLC 47 65 39 66 / 20 10 0 0 BVO 44 59 36 63 / 0 10 0 0 FYV 44 56 36 59 / 20 10 0 0 BYV 46 55 37 57 / 20 10 0 0 MKO 46 61 40 64 / 10 10 0 0 MIO 45 56 37 60 / 0 10 0 0 F10 46 61 40 65 / 0 10 0 0 HHW 50 68 44 67 / 80 0 0 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ LONG TERM....30