Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/04/19

National Weather Service Albany NY
1014 PM EDT Fri May 3 2019 .SYNOPSIS... A low pressure system and weak cold front will move across the region tonight with another round of showers and some isolated thunderstorms. The cold front will be south of the region tomorrow with some clouds and a few showers south and east of the Capital Region. A low pressure system moving across the Mid Atlantic States along the front Saturday night into Sunday may bring some rainfall back into the region especially south of the Interstate 90 corridor. A brief period of mainly dry weather is expected late Sunday into Monday with weak high pressure building in. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... As of 1014 PM EDT...Scattered to numerous showers continue to move across the region late this evening. While the main surface boundary and weak area of low pressure remain to our west, E-SE flow has resulted in marine influenced air mass to squelch any instability. Thunderstorms have been prevalent across central/northern PA this evening, but lightning has diminished into southern NY. This activity should weaken as it moves across our area during the overnight hours. 00Z KALY sounding showed very little elevated instability, so will remove mention of isolated thunder. Widespread showers will move back in associated with the activity in PA, but will decrease in intensity with only light/moderate rainfall rates around 0.1 to 0.25 inches per hour. Latest few hour runs of the HRRR indicating slower ending to the showers overnight into early Saturday morning, so pops were raised during this time. The occluded front and weak surface low will gradually move through. Patchy fog may form with the showers in the moist marine air mass. Low temps will be in the mid and upper 40s north and west of the Capital District and upper 40s to lower 50s from Albany south and east. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/... Tomorrow...The front settles south of the region near the PA-MD border and south of Long Island. Weak high pressure will be ridging in from the Great Lakes Region and southeast Canada. Some isolated to scattered showers may linger in the morning south of I-90 close to the I-84 corridor across NW CT, the mid Hudson Valley and southeast Catskills. The mid and upper level flow will continue to be zonal across the region. Cloudy or mostly cloudy conditions will continue through the morning into the early afternoon. The best chance of some sun mixing with clouds based on the deterministic guidance and Ensembles will be across the Upper Hudson River Valley and the southern Adirondacks, and possibly briefly into the Capital Region. Clouds will begin to thicken and lower late in the day especially across the southern zones with the a wave forming along the cold front over the OH Valley and Mid Atlantic States. We blended the latest MAV/MET/ECM guidance for max temps as the latest MAV guidance seemed too warm, especially if the clouds hold on with highs in the mid 50s to lower 60s over the higher terrain and mainly mid and upper 60s in the valleys with a few 70F readings in the mid Hudson Valley. Saturday night into Sunday...The 12Z GFS/NAM/ECMWF and several Ensemble members have trended south with the low pressure system and over running rainfall Saturday night into Sunday. The sfc low passes over the Chesapeake Bay region staying well south of Long Island. There is still some uncertainty with the zonal flow aloft, but we kept a slight to low chance of showers from the Capital Region/I-90 corridor south, except for portions of the Mid Hudson Valley/southeast Catskills, and NW CT where we went with likely/low categorical PoPs especially between 06Z- 12Z SUN...and continuing into the late morning/early pm with a quarter to half inch of rain. The threat for some light rain continue during the day Sunday further north, but based on the latest trends locations from Albany north and west may stay mainly dry with some clouds lingering north of the wave. A few showers may linger south and east of the Capital Region in the afternoon with the mid and upper deformation zone. If the trend southward continues, then we may lower PoPs further north. Low temps will be in the 40s to lower 50s with a few upper 30s in the Adirondack Park. Max temps on Sunday will depend on the degree of cloudiness and rainfall extent. We leaned closer to the cooler MET guidance and went with warmer max temps over the northern zones where some sunshine max mix with clouds. Highs north of the Capital Region in the Upper Hudson River Valley may be in the upper 60s with mid 50s to lower/mid 60s expected across the rest of the region with some locations in the mid Hudson Valley/NW CT stuck in the upper 50s. Sunday night into Monday...A drying trend is expected with weak ridging building in from the OH Valley, and the lower Great Lakes Region. Some partly cloudy/mostly clear skies are expected Sunday night with low temps falling into the 40s with light to calm winds. A prefrontal sfc trough may cause some clouds to increase Monday well in advance of a cold front. A few sprinkles or isolated showers may pop-up over the higher terrain especially north and west of the Tri-Cities though the synoptic forcing looks weak and our forecast leans closer to the NAM/ECMWF at this point. Max temps trend closer to normal for early May with 60s to lower 70s across the forecast area. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... Another wet and cool week looks to be in store for eastern NY and western New England in the long term forecast. We will be closely monitoring a stalled stationary boundary and waves of low pressure riding along it Wednesday through Friday which look to bring us multiple chances for showers and even periods of rain. Read on for details. We start the period Monday night with high pressure in place off the mid-Atlantic coast as an ana front gradually sinks southward through Ontario, Canada. We should enjoy mild and dry weather ahead of the approaching front Monday night into the first half of Tuesday with southerly flow leading to high temperatures in the upper 60s to even low-mid-70s for the mid-Hudson Valley and Litchfield County, CT. However, our approaching ana front will be sliding through our region Tuesday, especially during the afternoon, from the Adirondacks through the Capital Region and eventually the mid-Hudson Valley with surface winds shifting north or northwest on the leading edge of the showers. This is a classic signature of an ana front and most areas should experience a noticeable temperature drop as the showers arrive as a chilly Canadian air mass noses southeast into the Northeast in its wake. Temperatures Tuesday night should fall into the 40s to near 50. Mildest Just how far south and east the ana front penetrates is still uncertain as the ECMWF shows the front reaching well into the mid- Atlantic by 12z Wednesday while the GFS and CMC-NH shows it stalling in southern New England/near NYC. For now, sided closer to the GFS/CMC-NH but still thinking the cool Canadian high air mass overspreads most of our region, leaving us with with another stretch of below normal temperatures Wednesday through Friday. Temperatures likely do not have much a diurnal change with highs remain in the 50s to near 60 and lows in the upper 40s/low 50s due to persistent easterly/southeasterly flow maintaining a cool, marine influenced air mass over eastern NY and western New England. While there remains uncertainty with the exact placement of our stalled boundary, the general consensus within the global guidance supports fast zonal flow persisting for the second half of the week with embedded weak vort maxes passing within it that should lead to multiple chances for showers. Thus, we have placed widespread chance POPs for each period Wednesday to Friday to account for this pattern. Should the ECMWF be correct with its placement of our stalled boundary much further south in the mid-Atlantic, Wednesday may end up being a dry yet cool day. A stronger low pressure system looks to develop in the Midwest and push eastward during the Thursday/Friday timeframe which could lead to more widespread and steadier areas of rainfall. We placed likely POPs in this window to account for this system. Should any elevated instability be associated with this low, any areas of convection could lead to enhanced rainfall amounts. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... Widespread showers moving across the KALB/KGFL/KPSF corridor early this evening, while most of the shower activity remains just north of KPOU. Conditions generally MVFR, although persistent IFR cigs remain at KPSF. This first batch of showers should move through by mid evening, although cigs will continue to gradually lower with the approach of the occluded boundary. Also, patch fog is expected to develop in the most marine air mass. Conditions are expected to become widespread IFR by late this evening into the overnight hours. Another batch of showers will move across much of the region overnight as the occluded boundary passes through. A few rumbles of thunder will be possible but will be too isolated to mention in TAFs. Conditions should remain IFR through the overnight hours into early Saturday morning. Showers will end by Saturday morning, with conditions gradually improving to MVFR. Skies should remain BKN-OVC Saturday afternoon, but cigs are expected to improve to VFR levels by around early afternoon. Winds will be light and variable tonight, becoming north- northwest around 5 kt on Saturday. Outlook... Saturday Night: Low Operational Impact. Slight Chance of SHRA. Sunday: Low Operational Impact. Slight Chance of RA. Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: Moderate Operational Impact. Chance of SHRA. Tuesday Night: Moderate Operational Impact. Chance of SHRA. Wednesday: Moderate Operational Impact. Chance of SHRA. && .FIRE WEATHER... A weak cold front will move across the region tonight with another round of showers and some isolated thunderstorms. The cold front will be south of the region tomorrow with some clouds and a few showers south and east of the Capital Region. A low pressure system moving across the Mid Atlantic States along the front Saturday night into Sunday may bring some rainfall back into the region especially south of the Interstate 90 corridor. RH values will increase close to 100 percent tonight in the rain, and drop to 50 to 65 percent tomorrow afternoon. The RH values will increase once again to 85 to 100 percent Sunday morning. The winds will be light and variable at less than 10 mph tonight and become north to northeast 5 to 15 mph on Saturday before becoming light and variable at less than 10 mph on Saturday night. && .HYDROLOGY... Showers and isolated thunderstorms will affect our region late this afternoon into tonight with a weak cold frontal passage. Rainfall amounts should range between two tenths and and three quarters of an inch. There could be locally heavier amounts in any isolated thunderstorms. This rain is not expected to cause river flooding at this time, but flows will remain high. Some ponding of water on roadways and poor drainage flooding of low-lying areas is possible. Generally dry conditions are expected Saturday except south of the Capital Region where some very light rain amounts are possible. Low pressure tracking south of Long Island Saturday night through Sunday will bring another chance of rain to our area especially south of the Interstate 90 corridor in the mid Hudson Valley, southeast Catskills, and NW CT where a quarter to half an inch is possible. Within bank rises are possible, but no flooding is expected. A brief spell of mainly dry weather is expected Sunday night into early next week, before wet and unsettled weather returns late Tuesday through the mid week. Flows will remain high for early May. Please visit our Advanced Hydrologic Prediction Service /AHPS/ web page for specific area rivers and lakes observations and forecasts. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Wasula NEAR TERM...JPV/Wasula SHORT TERM...Wasula LONG TERM...Speciale AVIATION...JPV FIRE WEATHER...NAS/Wasula HYDROLOGY...NAS/Wasula
Area Forecast Discussion
National Weather Service Boston/Norton MA
1006 PM EDT Fri May 3 2019 .SYNOPSIS... A wave of low pressure will bring another period of rain later tonight and Saturday morning, with some improvement Saturday afternoon. Another low pressure tracking south of New Eng may result in some showers Sunday but it is likely the steadiest rain will remain to the south. High pressure brings dry, seasonal conditions Monday and Tuesday. Another frontal system may bring more showers at mid week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Main change to the forecast this evening was to increase rainfall chances overnight. Last few runs of the HRRR and time- lagged ensemble HRRR seemed to have a decent handle on timing and location of showers this evening. Relied upon them heavily to update timing of rainfall. Only real threat of thunderstorms overnight remained towards the south coast of RI and MA, where a lone thunderstorm was already marching east. Not expecting severe weather from this thunderstorm, as there is simply not enough energy to work with. This storm was barely capable of producing lightning. Once the showers presently in our region move off to the east, watching another batch of widespread showers towards southeast PA which should arrive in our region late tonight into Saturday morning. Still thinking the stronger convection will not be as prevalent in southern New England, but cannot completely dismiss the idea of an isolated thunderstorm or two. Minor tweaks to temperatures overnight. Previous Discussion... Next mid level shortwave approaches from the Great Lakes late tonight and the guidance is showing a frontal wave developing along the mid Atlc late tonight. Deepening moisture and modest forcing for ascent will result in a renewed area of showers developing and moving into SNE late tonight and Sat morning. The showers should be focused more along and south of the Pike and isold t-storms are possible near the south coast where 200-400 J/kg of MUCAPE indicated. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/... Saturday... While it will be drying from the north Sat, a wet morning is likely near the south coast into RI and SE MA with improvement in the afternoon as some breaks of sunshine should develop with modest mid level drying. Exception will be near the south coast and especially Cape/Islands where clouds and patchy fog may persist. While it should be mainly dry into the afternoon, there is a low risk for a brief shower developing away from the coast as models generate weak instability. Light easterly flow will hold temps in the 50s along the E coast of MA, but temps should recover into the 60s away from the coast and possibly near 70 in the CT valley. Saturday night... Yet another shortwave will be approaching with the frontal wave tracking off the mid Atlc coast. Low amplitude shortwave with flat flow and guidance has trended southward with deeper moisture. There is uncertainty with how far north showers and steadier rainfall gets but it is looking more likely that the steadier and heavier rainfall will remain to the south. Still, some showers are expected overnight as moisture deepens across the region. Areas of fog expected again near the south coast. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Highlights... * Best chance of showers further south on Sunday * Dry and seasonable conditions Monday into Tuesday * Cold front brings showers through late Tuesday/Wed * Another wet system arrives Thursday or Friday Sunday... So one of the biggest adjustments to the forecast is in rainfall potential during the day on Sunday. While rain is still expected, trends over the past 24 hours have been toward high pressure to our north keeping the best forcing and moisture suppressed further south, and thus the heaviest precip offshore. Guidance still favors showers, especially south of the MA Pike and best chances during the morning hours. The second half of the weekend overall looking like less of a washout, even potential for some sun; better chance of breaks in the clouds as we go through the day. Onshore winds continue out of the northeast as we remain on the north side of the low. Breezy winds expected along the south coast in closer proximity to the tightest surface pressure gradient. Given less rain/cloud potential, high temps have been raised a bit into the upper 50s along the coast, 60s inland. Monday and Tuesday... A drier and seasonable few days on tap to start the week. Early Monday the low exits to the east, replaced by surface/mid level ridging. A drier column and subsidence under the high brings a mix of clouds and sun Monday with light winds and highs in the 60s, warmer in the CT valley. Looks like a perfect day to come check out the Hurricane Awareness Tour being held by our office at Quonset State Airport from 2-5 PM! 12Z guidance has come into better agreement on the timing of a trailing cold front which moves through Tuesday/Tuesday evening. Remnants of a low over Hudson Bay, it will bring some showers along and ahead of the front which then hangs up near southern New England as it becomes parallel to zonal steering flow. Southerly surface winds bring warmer temps during the day Tuesday, into the 70s for many in the interior. Wednesday through Friday... Models haven`t been handling this progressive spring pattern very well in the extended, and that becomes more evident as uncertainty increases by Wednesday. Some question as to how long the overnight precip lingers into Wednesday as flow remains zonal. With no substantial shortwaves to get things moving, the front may linger in the neighborhood keeping rain chances into late Wednesday. For now have trended drier through the day to reflect a drier ensemble mean guidance. Tuesday looks like the warmest day of the week. Friday and beyond we return to a fairly cool patter in the 50s and 60s. Next wet weather system comes sometime late week. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Saturday Night/...Moderate confidence. Tonight... Widespread IFR/MVFR cigs with areas of LIFR stratus and fog along the south coast. Another round of showers will mainly move across northern MA late this evening. Still expecting a round of showers to move across the region after midnight and be focused mostly along and south of the Mass Pike with some scattered showers possible over northern MA. An isolated thunderstorm or two remains possible along the S coast. Saturday... MVFR/IFR in the morning with showers focused near the south coast, then improving to VFR in the afternoon. A few afternoon showers may develop in the interior. Areas of stratus and patchy fog may persist through the day across the Islands and possibly Cape Cod as well. Saturday night... VFR/MVFR cigs trending toward IFR/MVFR with areas of fog along the south coast. More showers may develop late Sat night, mainly south of the Pike. KBOS Terminal...Moderate confidence in TAF, mainly due to timing of showers. KBDL Terminal...Moderate confidence in TAF, mainly due to timing of showers. Outlook /Sunday through Wednesday/... Sunday: Mainly VFR, with local IFR possible. Breezy. Chance RA. Sunday Night through Monday Night: VFR. Tuesday: VFR. Slight chance SHRA. Tuesday Night: VFR. Chance SHRA. Wednesday: Mainly VFR, with local MVFR possible. Slight chance SHRA. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Saturday Night/...High confidence. Relatively light winds and seas through Saturday night with easterly flow. The main impact for mariners will be poor vsbys at times in areas of fog, especially for south coastal waters. In addition, showers are likely especially late tonight into Sat morning and can`t rule out an isolated thunderstorm or two. More showers are possible Sat night. Outlook /Sunday through Wednesday/... Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain. Sunday Night through Monday Night: Winds less than 25 kt. Seas up to 5 ft. Tuesday: Winds less than 25 kt. Seas up to 5 ft. Slight chance of rain showers. Tuesday Night through Wednesday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...None. && $$ SYNOPSIS...KJC/BW NEAR TERM...Belk/KJC/BW SHORT TERM...KJC LONG TERM...BW AVIATION...Belk/KJC/BW MARINE...KJC/BW
Area Forecast Discussion
National Weather Service Charleston SC
1015 PM EDT Fri May 3 2019 .SYNOPSIS... A weak area of low pressure will move northeast of the area tonight and dissipate through Saturday morning. A cold front will then push through the region by Sunday night, followed by drier high pressure into the middle of next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... The wave of low pressure is no longer easily identified, although with the best moisture transport now well offshore and nocturnal influences in place over land, the risk of any additional convection is long over with. Instead the main concern for the rest of the night will be the continued formation of fog, and also the development and build down of stratus. The overall potential for fog looks high, but where the best coverage will be is still somewhat uncertain, as there remains no consensus between the models. We did start the development of fog a few hours earlier than previous forecasts, and based on the RAP and HRRR condensation pressure deficits, we have included mention of dense fog and a possible Dense Fog Advisory in the Hazardous Weather Outlook. It`ll certainly be a warm and humid night, with temps holding above 70F for most places through 1 or 2 AM, while actual lows will barely reach 65-70F. Previous discussion... The wave of low pressure is seen in surface observations across southern Georgia, and this feature will continue progress slowly northeast and will be near or just northeast of the Santee River by daybreak. Lingering boundaries still have decent thermodynamics and moisture to work with the maintain isolated to scattered showers and a few t-storms through mid evening. Fog potential still looks good, with RAP and HRRR condensation pressure deficits favorable for at least patchy dense fog late tonight. Given the wet grounds, this seems highly plausible and we certainly could need a Dense Fog Advisory or at least a Special Weather Statement closer to daybreak, pending the amount of dense fog that occurs. Discussion from 409 PM... This Evening and Tonight: A warm and moist airmass will linger across the region early, helping produce a few showers and thunderstorms well inland where previous activity has not worked over the environment. Convection will remain sub- severe, but PWATS around 1.75 inches along with the slow movement of activity could produce brief moderate/heavy downpours for the next hour or two across inland areas. A weak wave/low will continue to drift across the area tonight. Despite some convergence associated with this feature, showers and/or thunderstorms are expected to rapidly decrease in coverage late evening into early tonight mainly due to diurnal heat loss. Once activity diminishes, cloud cover should decrease through midnight, potentially setting up an environment favorable for fog late. The combination of limited cloud cover, light winds, wet grounds from previous rains and sfc dewpts in the upper 60s to around 70 should favor at least patchy fog across all areas late tonight. The greatest chance of fog appears to be across inland areas of Southeast South Carolina where temps become cooler late. In general, lows should range in the mid/upper 60s away from the coast. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/... Saturday and Saturday night: The forecast area will be positioned within the southwesterly flow aloft ahead of a southern stream shortwave moving along the Gulf Coast. At the surface, the weak wave of low pressure will move to the northeast and dissipate, leaving behind a very summerlike environment for the afternoon. Temperatures should rise into the upper 80s away from the immediate coast, with dewpoint values in the upper 60s to low 70s. Models are in pretty good agreement regarding coverage of showers and thunderstorms, with the main focus being across our inland zones closer to the Midlands. This area should see the most instability and best low level convergence. Soundings show around 25 knots of flow in the lowest 5 or 6 km of the atmosphere, so there could be enough shear to produce some interesting multi-cell clusters. The location of the strongest storms will likely be determined by boundary interactions through the afternoon. We can`t totally rule out one or two strong to marginally severe storms, but it still looks like the best environment will be present on Sunday. Rain chances are highest inland, in the 50-60 percent range and taper into the 20-30 percent range at the coast. Convection will move further inland and dissipate through the evening. Then late Saturday night showers and thunderstorms could approach from the west as along and ahead of a cold front. Expect a mild night with lows likely not falling below 70 along the coast. Sunday and Sunday night: The trough axis will pass through and help push a weak cold front through the forecast area during the day. Thunderstorm coverage should increase from the west in the morning and peak in the afternoon. Model agreement is good, so rain chances have been increased into the 60 percent range. The dynamics are much improved on Sunday, as model soundings show the mid-level flow increasing into the 50 knot range. This should yield deep layer shear values on the order of 35-40 knots. Instability is more of a question mark. The GFS shows CAPE in the 1000-1500 J/kg while the NAM is a bit higher. This combination of shear and instability make the Sunday severe threat a bit more interesting. As such, we remain in a Marginal Risk area from SPC in the day 3 severe weather outlook. Highs should top out in the mid 80s, but it wouldn`t take much sun to rise into the upper 80s. Overnight the front will move to the coast. Could still see some isolated showers or thunderstorms, but rain chances are much lower and the severe threat diminished. Monday: The front will move offshore, and zonal flow will prevail through the day. The day will be very summerlike with highs in the mid to upper 80s in a very weakly forced environment. Diurnal heating should be enough to kick off at least isolated convection. Added a 20 percent chance of thunderstorms to the forecast. The larger scale flow will be northerly, and the development of the afternoon sea breeze should provide enough convergence to initiate convection. There is a bit more mid/upper level dry air so DCAPE values are higher than previous days. Could see one or two strong to marginally severe thunderstorms. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... Moderate to high confidence this period. Mainly dry high pressure should prevail into mid week before rain chances likely increase ahead of another cold front. The main question at this point is how quickly this occurs, possibly as early as Wednesday. Either way it looks unsettled through the rest of the period with the front likely still west of the area. Temperatures will cool a bit mid week before increasing again, but likely staying above normal through the period. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... While there could be a few brief episodes of MVFR weather early tonight, the better chance for flight restrictions will occur after 07-08Z. This will be as a result of low stratus and fog developing due to light winds, wet grounds and near 100% relative humidity. We anticipate at least low-end MVFR, if not IFR/LIFR, before VFR returns by about 1330Z and continues into the early afternoon, before scattered showers/t-storms develop across the area. Until trends are better defined we won`t show anything more than VCTS after 18-19Z, but periodic flight restrictions are possible in any convection moves over the terminals. Extended Aviation Outlook: Fog and/or low clouds could impact both CHS and SAV each morning through the weekend. However, greater chances of flight restrictions are possible with showers and/or thunderstorms Saturday and especially Sunday as a cold front nears the area. VFR conditions should prevail at both terminals by Monday. && .MARINE... Overnight: The center of weak low pressure will track across the coastal waters with little to no convective activity as it shifts off the northeast. Other than a wind shift from east- southeast to southwest after midnight, conditions will remain fairly quiet over all coastal waters. In general, wind speeds will remain at or below 10-15 kt while seas range between 2-4 ft. We did add mention of patchy fog in Charleston Harbor after 4 or 5 am, with some of the fog to slide into the nearby Atlantic waters as the late night land breeze develops. There certainly could be a need for a Dense Fog Advisory into Saturday morning. Saturday through Wednesday: The local waters will be situated between high pressure to the east and an inland cold front Saturday, driving south to southwesterly flow. Wind speeds should top out around 15 knots in the afternoon. On Sunday the gradient will be tighter as the front moves closer, and speeds will be a bit higher topping out in the 15-20 knot range. Monday winds look much calmer behind the departing cold front, but then increase modestly Monday night through Wednesday in onshore flow. Seas should generally fall into the 2-4 ft range through the period. Rip Currents: A Moderate Risk of Rip Currents continues through Saturday. && .CLIMATE... Record high min temps for May 4: KCHS: 70/1990 KCXM: 73/last set in 1990 KSAV: 70/last set in 1984 Record high min temps for May 5: KCHS: 70/last set in 1996 KCXM: 73/last set in 2012 KSAV: 70/last set in 2012 && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM... SHORT TERM...RJB LONG TERM...RJB AVIATION... MARINE... CLIMATE...
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
325 PM MDT Fri May 3 2019 .SYNOPSIS... We will be mostly dry over the next seven days, with just a slight chance for thunderstorms in the Sacramento Mountains this weekend. Temperatures this weekend will run a couple of degrees warmer than Friday`s high temperatures. For the start of next week we will see breezy to windy conditions in the afternoons and then we will be a little cooler for the middle of next week. && .DISCUSSION... We continue to be in a generally quiet weather pattern, today through the weekend. Some deeper moisture continues to lurk just to the east of the area and this moisture may bring a slight chance for thunderstorms to the Sacramento Mountains and eastern Hudspeth County on Saturday and again on Sunday. But more likely some moisture from the east will leak into the eastern part of the area, but things will dry back out before convection can get going by late afternoon. The only thing we will need to keep an eye on is the fact that sometimes a line of thunderstorms well to our east will push a long lived moist outflow boundary back to the west. This could allow moisture to move further west and give a better chance of thunderstorms to the area. Earlier runs of the HRRR model kind of hinted at this, for later tonight, but the later runs have been weakening this west push, so for now I`ll keep just a slight chance of thunderstorms in the forecast for the Sacramento Mountains on Saturday and both the Sacs and eastern Hudspeth County on Sunday. The rest of us will stay dry and warm as westerly winds push our high temperatures around 5 degrees above average, which would allow most lowland locations to flirt with the 90 degree mark on both Saturday and Sunday. For Monday our attention will turn out west as the next upper level storm system begins to move toward the region. On Monday, the upper level low will still be well to our west, but the southwest flow out ahead of it will allow some moderately stronger winds aloft to move across the region, so we will be breezy to windy on Monday afternoon. Then on Tuesday as the upper level trough opens up, it will help give us another windy day. We may approach wind advisory level in western New Mexico. The upper level trough will pass across the Four Corners region, which should keep it far enough north to keep the associated rain out of the area. As the trough swings by it will help usher in some cooler weather, so our highs for Tuesday through the end of the week will run a few degrees below average. The rest of next week looks quiet, as a second, weaker trough passes to our north with little impact on our weather. Just beyond this forecast period, both the extended GFS and ECMWF bring rain chances into the region, but for different reasons. The GFS brings a strong push of moisture in from the east to fuel some thunderstorms, while the ECMWF doesn`t have as strong an east push, it does sweep an upper level trough across New Mexico to generate some thunderstorms. We`ll have to wait and see which solution is correct or perhaps a drier solution will win out between the two. && .AVIATION...Valid 04/00Z-05/00Z... P6SM SKC-SCT250 through period. Winds generally SW to NW AOB 12KTS but will shift around to the E to SE over eastern zones during the overnight hours before turning back to the SW after 15Z. && .FIRE WEATHER... The weekend will feature warm temperatures with mainly single digit RH`s all areas except some parts of far eastern zones. A dryline will move west overnight and push back east during the daytime hours through Sunday with the westward push up to near the Rio Grande. Isolated showers and thunderstorms are possible wherever this dryline is located by early to mid afternoon which should be east of a line from Alamogordo to Sierra Blanca. Winds through the weekend will mainly be under 15 mph. For early next week, an upper low will be moving out of southern California and into the Four Corners region. This system will bring increasing winds and possible critical conditions with best chance coming on Tuesday with near critical Monday. As this system lifts out, temperatures will cool down to near normal for the remainder of the week with slightly higher relative humidities, but still likely remaining in the lower to mid teens for the lowlands. && .PRELIMINARY POINT TEMPS/POPS... El Paso 59 89 62 91 / 0 0 0 0 Sierra Blanca 53 83 58 86 / 0 0 0 10 Las Cruces 52 87 55 87 / 0 0 0 0 Alamogordo 53 85 57 89 / 0 0 0 0 Cloudcroft 38 64 42 66 / 0 20 0 20 Truth or Consequences 54 87 56 87 / 0 0 0 0 Silver City 49 77 52 79 / 0 0 0 0 Deming 49 87 52 87 / 0 0 0 0 Lordsburg 49 86 52 86 / 0 0 0 0 West El Paso Metro 58 87 62 90 / 0 0 0 0 Dell City 52 84 56 92 / 0 0 0 20 Fort Hancock 56 90 62 94 / 0 0 0 10 Loma Linda 55 83 59 85 / 0 0 0 0 Fabens 57 90 62 92 / 0 0 0 0 Santa Teresa 53 87 57 89 / 0 0 0 0 White Sands HQ 59 86 62 89 / 0 0 0 0 Jornada Range 50 87 54 87 / 0 0 0 0 Hatch 50 87 52 89 / 0 0 0 0 Columbus 54 88 57 89 / 0 0 0 0 Orogrande 53 85 57 89 / 0 0 0 0 Mayhill 43 72 46 76 / 0 20 0 20 Mescalero 42 72 46 76 / 0 20 0 20 Timberon 40 69 44 74 / 0 20 0 20 Winston 40 80 41 81 / 0 0 0 0 Hillsboro 49 85 51 86 / 0 0 0 0 Spaceport 48 86 51 87 / 0 0 0 0 Lake Roberts 39 79 41 80 / 0 0 0 0 Hurley 46 81 49 82 / 0 0 0 0 Cliff 40 85 43 86 / 0 0 0 0 Mule Creek 46 80 49 81 / 0 0 0 0 Faywood 49 81 52 82 / 0 0 0 0 Animas 48 88 52 87 / 0 0 0 0 Hachita 47 87 50 87 / 0 0 0 0 Antelope Wells 49 87 53 87 / 0 0 0 0 Cloverdale 50 82 53 81 / 0 0 0 0 && .EPZ WATCHES/WARNINGS/ADVISORIES... NM...None. TX...None. && $$ Brice/Grzywacz
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
852 PM CDT Fri May 3 2019 .UPDATE... Quick Update. The main concern continues to be the line of thunderstorms from El Indio to Hondo to San Antonio to New Braunfels, Bastrop, and Giddings. Behind the line light rain continues. There continues to be many threats with this line mainly strong gusty winds and heavy rainfall leading to flash flooding. We have seen numerous reports from Dripping Springs and Austin of evacuations, water rescues, and low water crossings closed. We continue to urge people to not travel tonight if they don`t have too. We have also seen little spin up circulations on the northern end of the line in Bastrop County headed into Lee County and also in Guadalupe county. The good news is that the this line will continue to move off to the east and southeast and should clear our area by about 3 am. Dry weather is in the forecast for tomorrow and Sunday before more rain next week! Other than dropping counties from the Severe Thunderstorm Watch that are now behind the line PoPs have been adjusted to fit radar trends and hourly grids were also trended. && .PREV DISCUSSION... /ISSUED 646 PM CDT Fri May 3 2019/ AVIATION... Thunderstorm complex near AUS is expected to begin propagating towards SAT/SSF by 02Z with heavy rainfall associated with this complex producing IFR/MVFR visibilities and ceilings through 08Z before it clears Interstate 35. Stronger cells may be able to produce wind gusts near 40 knots. Stray TSRA may skirt DRT but will handle impacts with amendments as confidence was not high enough to maintain a TEMPO based on latest radar presentation. Once the line exits to the east with the passage of an associated mid-level trough axis now over West Central Texas, have trended ceilings close to HRRR output with VFR ceilings prevailing through the end of the period. May see a few MVFR ceilings attempt to develop at all of the terminals closer to sunrise as southerly low level winds persist behind this system, but veering winds should clear out any ceilings that develop mid to late morning Saturday. Otherwise, light and variable winds will become northeasterly 5-10 knots during the day Saturday for AUS/SAT/SSF and southeast around 10 knots for DRT. PREV DISCUSSION... /ISSUED 440 PM CDT Fri May 3 2019/ UPDATE... Quick update for Severe Thunderstorm Watch 127 that has been issued for the entire South Central Texas area. Strong to Severe thunderstorms are already ongoing across the Edwards Plateau in Northern Val Verde County and across Northern Kendall/SE Gillespie Counties. This activity will gradually move east and southeast through the evening and into the overnight hours. PREV DISCUSSION... /ISSUED 246 PM CDT Fri May 3 2019/ SHORT TERM (Tonight through Saturday Night)... We`ll take "All Scales of Motion" for $500 today across South Central Texas. Fortunately, the variety of forcings from local and low (boundaries) to region-wide and high (shortwave trough and jet streak exit region) have dissipated into the background regime or are consistent enough to settle into a climatologically-favorable morphology for this afternoon through tomorrow morning. The 12Z NAM/GFS/ECMWF and more recent TTech WRF/HRRR/HREF runs are in general agreement with that evolution, from isolated to scattered storms moving from West Texas and Mexico into the Rio Grande Plains this afternoon, to an eventual merging of cold pools and an MCS rolling though the southeastern 1/2 of the area. Some supercells are possible through early evening before the cold pools merge. The greatest severe threat will be damaging wind, with lesser threat of large hail and a very small chance for a tornado or two. The prime severe threat area will be near supercells along the Rio Grande through about 7-8 pm, then transitioning to along and east of I-35 by 10-11 pm. Of special concern area is along and south of U.S. 90 from Uvalde to San Antonio to Gonzales, where the models indicate the highest damaging wind threat. Rainfall amounts will be spotty in the west, from 1/10 inch up to one inch. Locations in the middle should see 1/4 to one inch, and locations along and east of I-35 1 to 2 inches. A few spots east of I-35 may see up to 4 inches. Some minor flash flooding is possible due to the rain/runoff from storms earlier today, in addition to the storms expected tonight. The good news is the shortwave trough will move east and a rapid clearing/drying trend from west to east will occur on Saturday. Rain should be over by midday except for all but the far eastern coastal plains, and rain should end there by mid-afternoon. Some fog is likely late Saturday night along and east of I-35, but that will be addressed by later forecasts when the clearing trend and near-ground wetness after the rain are more evident. LONG TERM (Sunday through Friday)... Sunday is the day for outdoor activity for the next week, with low- amplitude ridging is over the area. Temperatures will be seasonal and relative humidity fairly low after daytime heating dissipates morning fog. The longwave pattern will become increasingly favorable for severe storms and heavy rain as next week progresses, with a large and digging western U.S. trough, and a strengthening Jet Stream across northern Mexico and into Texas. Shortwave troughs will eject out of the longwave trough every 24-36 hours to provide the primary lift. At this time, Monday, Wednesday, and Friday appear to be the days with the best chances for rain. The chances for severe storms will increase for Wednesday and Friday as the shortwave troughs are deeper and the boundary layer has more time to moisten and increase instability. Friday is of the highest concern, as a cold front appears to stall from west to east across our area. Diffluent 1000-500 mb thickness over our area points to slow-moving, stalling, or possibly even back-building convection. Combined with echo training along the front, that is a recipe for very heavy rain and significant flash and river flooding. While at this forecast range details are variable and fuzzy, pay attention to the how the forecast evolves through the week. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 80 64 80 62 83 / 50 70 20 0 0 Austin Bergstrom Intl Airport 81 62 80 61 83 / 50 70 20 0 0 New Braunfels Muni Airport 81 64 80 61 83 / 40 70 20 0 0 Burnet Muni Airport 77 61 78 60 81 / 60 60 10 0 0 Del Rio Intl Airport 76 64 85 65 85 / 70 40 10 0 - Georgetown Muni Airport 77 63 79 60 83 / 60 70 20 0 0 Hondo Muni Airport 81 64 83 62 85 / 40 60 10 0 0 San Marcos Muni Airport 82 64 80 61 83 / 50 70 20 0 0 La Grange - Fayette Regional 80 66 82 63 85 / 60 80 30 0 0 San Antonio Intl Airport 79 64 81 63 84 / 40 70 10 0 0 Stinson Muni Airport 82 66 81 63 84 / 40 80 10 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Aviation...Huffman Short-Term/Long-Term...Treadway Public Service/Data Collection...33
Area Forecast Discussion
National Weather Service Grand Forks ND
952 PM CDT Fri May 3 2019 .UPDATE... Issued at 952 PM CDT Fri May 3 2019 Additional adjustments made to sky grids in the near term to reflect clearing and dissipation of showers/thunderstorms in our east. Showers over north central ND still expected to move eastward generally along International Border with very light amounts. Very sharp cutoff in surface/BL Tds behind frontal passage this evening, with fog developing over parts of west central MN in warm/moist sector but clearing and Tds in the teens in ND. This deep dry air will limit potential for measurable precip further south tonight. Better forcing eventually arrives Saturday as a second stronger cold front pushes through our CWA. A period of isolated to scattered light showers is advertised by consensus of higher resolution guidance (though this could be oversold in coverage of measurable). Depending on mixing behind this front we could see a period of gusty winds as well, but mixing heights at time of post frontal LLJ are still not lining up enough to increase winds too much. UPDATE Issued at 701 PM CDT Fri May 3 2019 Isolated thunderstorms redeveloped/intensified along prefrontal surface trough in far northwest MN. RAP analysis indicated MU CAPE (dominated by surface parcels) in the 500 J/KG range. Freezing heights in the 5000 FT AGL range (-20C heights in the 14KFT range) have supported better hail potential despite limited updraft heights. With loss of daytime heating, weaken of updrafts has been observed. In the meantime strong low level vorticity in proximity to pre-frontal trough/wind shift line, combined with steep low level lapse rates has supported funnel cloud development with updrafts that develop. Impacts from these are limited, but will remain possible through sunset when loss of daytime heating/favorable low level lapse rates will end the threat. Adjustments made to account for lingering thunderstorm/shower activity early this evening and associated sky cover. Also added patchy fog to our southeast counties based on consensus of latest short range guidance. && .SHORT TERM...(This evening through Saturday night) Issued at 307 PM CDT Fri May 3 2019 Challenge for the short term period is convective activity this evening which includes thunder potential and end timing. There is a narrow ribbon of instability with up to 500J/kg of CAPE that has developed within the WAA band of precip and SFC front with westerly wind push. Will see the activity continue to push to the east late this afternoon into the early evening. Precipitation is expected to be east of the area by 7 to 8 pm. Overnight tonight cold front is expected to drift south and bring some slight shower chances to the northern half of the FA. Then tomorrow the slight shower chances slide into the central and southern portions of the area. Temps remain on the cool side of normal with highs in the 50s. .LONG TERM...(Sunday through Friday) Issued at 307 PM CDT Fri May 3 2019 NW flow aloft gradually becomes more zonal as an upper low moves from wrn Ontario into Hudson bay. The zonal pattern persists through Mon night, when a short wave moves across the area. The wave could bring thunder to the far south with a rain-snow mix or snow late Mon evening. The upper level then transitions to a split- flow pattern with the northern stream over the northern tier keeping rather cool air in place, with daytime highs generally in the mid to upper 50s for the next work week. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 701 PM CDT Fri May 3 2019 Isolated showers/thunderstorms in northwest MN should move east and eventually dissipate after sunset this evening. Additional showers may move into the region from northcentral ND, but coverage is still a question (better chances near the International Border). VFR should prevail, unless a terminal is impacted by shower/thunderstorm. There is potential for fog to develop in west central MN late tonight, but confidence was too low to introduce to KBJI at this time. && .HYDROLOGY... Issued at 306 PM CDT Fri May 3 2019 Moderate flooding continues along the mainstem of the Red River from Oslo to the Canadian border. The Red River at Fargo/Moorhead and Grand Forks/East Grand Forks remains in minor flooding. Lastly, the Red River at Wahpeton/Breckenridge has fallen below flood stage and the warning has been cancelled. Although there will be a few showers and storms this afternoon, there will be little if any impact on the river system. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. River point flood warnings continue across portions of the region. Refer to the latest flood warnings and statements for detailed information on specific locations. && $$ UPDATE...DJR SHORT TERM...JK LONG TERM...Speicher AVIATION...DJR HYDROLOGY...Speicher
Area Forecast Discussion
National Weather Service Hastings NE
628 PM CDT Fri May 3 2019 .SHORT TERM...(This evening through Saturday night) Issued at 447 PM CDT Fri May 3 2019 Focusing on only the first 36 hours (three forecast periods) in this section, the main issues include: 1) Potential for a few marginally-strong storms through this evening with small hail/gusty wind potential (mainly in the northwest half of our coverage area/CWA)...2) Could some fog develop into mainly our southeast zones late tonight/Sat AM?...3) A somewhat better chance for a few strong to severe thunderstorms Saturday afternoon- evening as instability levels continue to creep upward (most of our CWA is now in a Marginal Risk from SPC on the Day 2 outlook). Otherwise, Saturday still looks to be our first day with widespread highs into the 70s in over a week. Taking a look at the current/recent weather scene as of 4 PM: Again, no big surprises today at all. Following a round of overnight rain across mainly our southern half (that dropped several tenths of an inch in some spots), a varied mix of clouds/sun and mainly dry conditions have prevailed through most of the day. However, as expected, a narrow/broken line of showers and fairly weak thunderstorms has in fact developed with the heating of the afternoon and along a low-level convergence zone along a surface trough in our far west-northwest CWA. Mesoscale analysis suggests up to around 500 J/kg of surface-based CAPE in the presence of at least 30-35KT of deep-layer shear, so this could be just enough to spark some small hail/gusty winds as these storms progress east-southeast late this afternoon into this evening, but severe storms appear rather unlikely. In other departments, fairly light southerly breezes prevail across most of the CWA ahead of the aforementioned surface trough axis. Temperatures are on track to top out in the 65-68 range most areas (roughly 3-4 degrees warmer than yesterday). In the big picture of the mid-upper levels, water vapor satellite and short-term model data continue to show a broad/large-scale trough extended over much of the CONUS, with various/mainly weak embedded disturbances within it (including some weak ripples aiding our ongoing convection). Now looking ahead forecast-wise through these next 3 night/day periods... This evening/tonight: See preceding paragraph on reasoning behind why a few marginally- strong storms cannot be ruled out, mainly northwest of a Fullerton-Kearney-Phillipsburg line. Based on the HRRR (which has performed very well so far with the ongoing activity), convection should gradually decrease in coverage/organization/intensity as it enters the southeast half of our CWA and diurnal heating starts to fade. That being said, have at least a slight/20 percent chance of showers/isolated storms extended into all but our far southeast zones this evening. While a few showers could linger until roughly midnight (especially in our northeast), the vast majority of the CWA should see a dry overnight period, marked by mostly clear to partly cloudy skies, and rather light breezes (largely around 5 MPH or less). That being said, there are subtle hints in a few models (especially GFS) that the very late night hours could feature a few developing sprinkles/light showers mainly in our southwest, so have added this small chance to the forecast. Otherwise, while not expecting widespread fog issues, have also added a generic "patchy fog" mention to some of our southeast counties, as both the HRRR/RAP visibility progs suggest this area would be most favored for possible fog development. Low temps tonight were actually nudged up 2-3 degrees, with most of the CWA expected to hold up well into the mid-40s (except near-40 far north around Ord area). Saturday daytime: Confidence has decreased a bit versus 24 hours ago regarding "exactly" how the precipitation/thunderstorm potential will play out. While most of the CWA should be dry most of the day, there are now at least small chances for spotty rain showers during the morning hours especially in our western half, along with suggestions from several models that especially the northwest half of the CWA could see at least isolated (perhaps scattered?) thunderstorm development during the mid-late afternoon. As a result, afternoon rain chances (PoPs) have been increased/expanded in area a bit versus previous forecasts, but again, most areas will probably get through the late afternoon hours dry. If any storms do pop with the heating of the afternoon and with the aid of a weak passing upper wave, agree with the SPC Day 2 that a Marginal Risk of severe is justified, as mixed-layer CAPE around 1000 J/kg is likely (roughly double of today), along with modest deep-layer shear around 30KT. Certainly a few marginally-severe storms appear possible in this environment. Otherwise, assuming that possible early-day showers don`t disrupt the low-level wind fields appreciably, it looks to be a touch breezy from the south much of the day, sustained 10-15 MPH/gusts to around 20 MPH. Temperature-wise, made very little change to high temps, aiming most areas into the 72-75 range, but if rain holds off well into the afternoon and skies remain mostly sunny, could easily see things climbing a bit warmer than advertised. Saturday evening-night: Don`t have a great feel for the details of storm coverage, but anything that develops late afternoon will easily continue into the evening, and in addition, the presence of a low level jet overnight could result in new/additional thunderstorm development even late into the night, at least on an isolated/random basis. Not expecting much of a severe weather risk after midnight, however. Again, not expected widespread coverage of storms/heavy rain, and thus why Pops are mainly just around 30 percent through the night. with continued southerly breezes, our trend of increasingly-warmer nights should continue, and have most of the CWA dropping no lower than upper 40s-low 50s. .LONG TERM...(Sunday daytime through Friday) Issued at 447 PM CDT Fri May 3 2019 General overview of this 6-day period: Just not enough time today to go into much detail, but here are the main takeaway points: 1) A very active weather pattern with SEVERAL chances for rain continues through Wednesday night, with the overall-best chances for more widespread rains focused during the Mon night-Wed night time frame as a larger-scale shortwave trough gradually approaches and passes through the Central Plains from the southwest. Very generally speaking, most of the CWA is expected to average 1.50-2.50" of total rainfall through the next week (per latest WPC 7-day QPF). Of course, with thunderstorms involved, some areas will surely see localized higher amounts. So whether you want it or not, plan on receiving a decent amount of rain at some point through the early-middle part of next week. 2) Severe thunderstorm potential: Along with Saturday (as described above), both Sunday and Monday carry potential for at least limited severe thunderstorm development, as they will be the overall-warmest and most unstable days of the next week. Although too soon to talk details, both the GFS/ECMWF suggest that CAPE of 1000-2000J/kg are likely in parts of the CWA on both of these day, and thus a severe risk could develop, especially during the favored late afternoon-evening hours. One limiting factor to a more widespread threat will be dewpoints probably "only" in the 50s, thus keeping "extreme instability" at bay, along with the fact that upper forcing appears fairly weak/disorganized, although a decent cold front could provide plenty of low-level forcing for Monday. Overall, agree with the current Day 3 Marginal Risk from SPC for Sunday, and fully expect the new Day 3 that comes out tonight to reintroduce at least a Marginal Risk to Monday (somewhat oddly to this forecaster, severe probabilities were not maintained for Monday on last night`s Day 4 outlook). 3) Temperature-wise, no major changes versus previous forecast, although especially Monday continues trending a bit cooler (4-7 degrees cooler than previous forecast), due largely to a bit faster invasion of the aforementioned cold front. Thus, it now appears that especially for Nebraska zones, Sunday is probably the overall-warmest day (mid 70s), with Monday then featuring a bit more of a gradient from only mid 60s far north to around 80 far south. For sure, Tues-Wed will be noticeably cooler with highs mainly in the 50s to low 60s, due in part to more widespread clouds and rain (and thus less potential for severe storms. Thursday also looks rather cool (highs in the 50s to near 60) before Friday nudged back up into the 60s. For those looking for truly dry days, very early indications suggest that Thursday should be mostly dry (despite some "iffy" rain chances in parts of the CWA in the latest forecast), with Friday looking like a better bet for dry weather. However, with this being a full week out, confidence is not overly-high. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Saturday) Issued at 616 PM CDT Fri May 3 2019 -SHRA should end shortly at GRI. VFR is forecast with a little bit of BR in the morning for GRI. The winds will be light overnight and with this evenings rain, figure GRI could see a little patchy light fog tomorrow at sunrise. Winds will be variable overnight and will become southerly as the weak high pressure over the region shifts east. Near the end of the TAFs denoted some VCTS as daytime heating along with a mid-level trough will move through the area tomorrow afternoon which may fire a few thunderstorms near the TAF sites. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ SHORT TERM...Pfannkuch LONG TERM...Pfannkuch AVIATION...Beda
Area Forecast Discussion
National Weather Service Houston/Galveston TX
804 PM CDT Fri May 3 2019 .UPDATE... Our brief respite between convective systems is about to end as large MCS/MCC is evolving over central TX early this evening. Storms are beginning to get more organized into a linear structure with pronounced sely motion getting established. Expect this MCS to track quickly southeast through the rest of the night, with ewd development into sern TX as main line surges towards the coast. Have cleaned up forecast in wake of earlier storms, and tried to time arrival of next round of tstms starting far nw counties 8-9pm and perhaps moving across Houston metro around 12a-3a window when it will also be reaching the middle TX coast. Intense rainfall rates can be expected with these storms, likely causing flash flooding especially over areas already drenched over the past couple of days. Will keep Flash Flood Watch in place to cover those locations, mostly along and north of I-10. However, these storms will be capable of localized flooding even outside the watch. Fortunately the complex/line will be moving quickly and should not linger over any one location. Although, this will increase the potential for strong to damaging winds as the line blows through. Large hail and an isolated tornado or two are also in play through the night with the stronger cores. In wake of this impluse, could still see lingering tstms through the morning, but then generally expect most of the rain/tstms to pull away as mid/upper level impulse continues moving ewd tomorrow. Evans && .DISCUSSION... && .PREV DISCUSSION... /ISSUED 645 PM CDT Fri May 3 2019/ AVIATION... VFR conditions this evening will deteriorate once again overnight. Per hires guidance, ongoing shra tstms in the Hill Country should evolve into a se/ese moving squall line across the region overnight. There are various timing differences and details between models so, in general, went with a compromise between the HRRR and Texas Tech WRF in regards to timing advertised in the 00Z set of TAFS. Expect amendments thru the night as trends are established. Most of the activity should be well east of the terminals before sunrise followed by a break in the action. Will probably need to throw mention of precip back into the TAFs at some point during the day Sat as the atmos recovers and daytime heating performs its magic. 47 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 66 82 63 85 65 / 90 50 0 0 0 Houston (IAH) 69 83 66 86 67 / 90 70 0 0 0 Galveston (GLS) 72 79 72 81 73 / 90 80 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Flash Flood Watch through Saturday afternoon for the following zones: Austin...Brazos...Burleson...Coastal Harris... Colorado...Grimes...Houston...Inland Harris...Madison... Montgomery...Northern Liberty...Polk...San Jacinto... Southern Liberty...Trinity...Walker...Waller...Washington. GM...NONE. && $$
Area Forecast Discussion
National Weather Service Jacksonville FL
921 PM EDT Fri May 3 2019 .UPDATE...Isolated showers and storms continue across Ne Fl due to a trough of low pressure interacting with a moist and unstable airmass over the area (SB Cape on 00z Jax sounding 3661J). This activity will gradually wane next several hours due to loss of daytime heating and trough begins to lift out. As the trough lifts out overnite deep layer ridging and dry air aloft will begin to move in and coupled with adequate low level moisture could lead to areas of low clouds and fog. High-res HRRR continues to show mainly low clouds (with patches of fog) developing near I-75 corridor and moving into much of the area early Sat am. Any patchy fog and low clouds should lift by mid morning. && .AVIATION...Isolated storms will continue to wane the next few hours but have VCTS at GNV and VQQ til around 03Z. High-res HRRR continues to indicate low clouds forming towards the gulf coast and spreading east. Have carried previous fcst of IFR at GNV aft 08Z and MVFR at JAX... VQQ...and CRG aft 09Z-10Z. Conditions improve to VFR by 14Z-15Z Sat. && .MARINE...Weak low pressure will move north of the waters tonight. A few isolated storms possible tonight. Rip Currents: Moderate risk. && .PRELIMINARY POINT TEMPS/POPS... AMG 67 88 68 83 / 0 0 30 60 SSI 70 85 70 83 / 0 0 10 50 JAX 68 90 69 87 / 20 0 10 50 SGJ 67 87 69 85 / 20 0 0 50 GNV 66 88 68 86 / 20 0 10 50 OCF 66 89 68 88 / 20 0 10 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. && $$ PP/KB
Area Forecast Discussion
National Weather Service North Platte NE
727 PM CDT Fri May 3 2019 .SHORT TERM...(This evening through Saturday night) Issued at 317 PM CDT Fri May 3 2019 Modest severe weather conditions are beginning to take shape across wrn and ncntl Nebraska Saturday with winds aloft increasing to around 35 Kts and MLCAPE around 2000 J/KG. This places the Bulk Richardson number between 25 and 50. The uncertainty in the forecast lies in how far west the return moisture can progress in the wake of the cold front moving through today. The forecast follows the short range blend which suggests isolated to scattered thunderstorm chances across swrn and ncntl Nebraska Saturday. For late this afternoon and tonight, just ordinary thunderstorms are expected given the weak winds aloft and lack of instability. The HRRR shows this activity developing from around Stockville north through Broken Bow and O`Neill. The situation Saturday looks toward the Cheyenne divide, ncntl Nebraska and southwest Nebraska for storm development along a weak frontal boundary. .LONG TERM...(Sunday through Friday) Issued at 317 PM CDT Fri May 3 2019 Thunderstorms may develop off the Black Hills Sunday with northwest flow aloft. If the storms develop diurnally across the Black Hills, around 18z-21z, then they would reach ncntl Nebraska early evening. These storms will be developing in a post-frontal environment with strong shear but limited instability. Thus, ordinary storm development would appear to be the operative mode. The forecast Monday is more uncertain. The NAM and GFS, place wrn and ncntl Nebraska in cool stable air; a post frontal environment. This will have a large impact on temperatures from the previous forecast which was advertising Monday as the warmest of the 7 day forecast. Cool air will remain locked into wrn and ncntl Nebraska Tuesday through Friday. This is the result of a blocking ridge in the north Pacific and downstream, a long wave trof across the Rockies. The forecast is fairly consistent predicting below normal temperatures for a few days. The long wave trof will be a source of upper level support for rain chances and even snow with the cold model, the ECM, suggesting snow at times Wednesday through Friday. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 723 PM CDT Fri May 3 2019 Skies will be mostly clear tonight behind a departing weak cold front. VFR conditions will prevail tonight through Saturday. Isolated to scattered thunderstorms could develop later Saturday afternoon into Saturday evening. Coverage will be limited and will not introduce into area TAFs at this time. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...CDC LONG TERM...CDC AVIATION...Taylor
Area Forecast Discussion
National Weather Service Memphis TN
744 PM CDT Fri May 3 2019 .UPDATE... Radar indicates a few showers and thunderstorms west of the region this hour. The latest high res guidance continues to indicate much of this weakening before it reaches the area, with the greatest chance for showers and storms areawide being after midnight. Current forecast is on track. Sending new zones only to update timing wording. ZDM && .PREV DISCUSSION... /issued 253 PM CDT Fri May 3 2019/ Short term...area of light showers has been able to maintain itself this afternoon. Not sure if they are linked to any embedded shortwave trough or just the overall continued southwest upper flow. Temperatures though have been cool enough...mainly in the low and mid 70s so the instability is struggling to reach a 1000j/kg CAPE. From this thunder and lightning should remain isolated at best through this evening. Tonight and tomorrow...main trough axis across New Mexico will swing through the Ozarks and Midsouth over the next 30 hours. Models remain in good agreement that thunderstorm coverage should ramp up quickly after midnight...and last through early afternoon Saturday...with brief periods of heavier rainfall and a low end threat for a strong or severe storm. Best threat for isolated severe storm will be south of I-40 where shear will be stronger. Then during the mid to late afternoon hours coverage should start to ramp down from west to east as an associated weak cold front slips through the region. By sunset only a few stray showers on the front may still be occurring in the east. Additional rainfall amounts will range from three-quarters to an inch and a half. Clouds and precipitation will keep tomorrow`s highs below normal. One would expect some clearing tomorrow night behind the front...but it appears the weak boundary layer flow may quickly allow for stratus...fog and even some patchy drizzle to form. Lows will fall into the mid 50s to low 60s. Sunday and Monday...surface high pressure will slowly slide from the Ohio River Valley to the Tennessee River Valley this period. Clouds should slowly erode Sunday morning with a light north breeze keeping highs in the 70s. Warmer temperatures are anticipated Monday as winds turn back from the south. High level clouds will skirt across the northern counties Monday night as convection fires on a warm front in the Lower Missouri Valley. Tuesday through Friday...long term solutions showing another repeating wet pattern setting up across the Southern Plains and Midsouth. Don`t feel each day will be a complete washout as the GFS is indicating...but overall rainfall amounts of 2-3 inches are likely this period. Severe weather could also be a factor like it was this past week...but pinpointing which day is questionable as upstream MCS activity in the ARKLATEX will have mesoscale affects on our area. Temperatures will start off above normal Tuesday...but lower to seasonal averages by Friday. JAB && .AVIATION... 00Z TAF cycle Variable conditions are expected over the upcoming TAF cycle featuring periods of showers and thunderstorms. Made an attempt at timing the initial round of storms based mainly on HRRR guidance, but also extrapolation from the development near and west of Little Rock. Amendments will likely be necessary, especially if additional storms develop ahead of stuff moving across central Arkansas. Winds will be light and variable overnight with mainly MVFR cigs as precipitation begins. Precipitation will linger across much of the the region tomorrow, but should not be continuous. Will maintain VCSH at MEM, MKL and TUP through the with precip ending at JBR after 19z. Winds will shift Northwest tomorrow, but remain fairly light. 30 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$
Area Forecast Discussion
National Weather Service Paducah KY
855 PM CDT Fri May 3 2019 .UPDATE... Issued at 855 PM CDT Fri May 3 2019 Updated the forecast to speed up the arrival of and eastward progression of showers and a few thunderstorms across the region tonight. A fairly solid line of convection will reach Carter and Ripley counties by 10 PM, and HRRR data pushes it eastward even to the Evansville Tri State by morning. Thunder will be most likely as the line arrives, and should become more sparse as it pushes east of the Mississippi. UPDATE Issued at 638 PM CDT Fri May 3 2019 The AVIATION section has been updated for the 00Z TAF issuance. && .SHORT TERM...(Tonight through Saturday night) Issued at 250 PM CDT Fri May 3 2019 Next upper level system headed our way will bring the region more rain and possibly a few thunderstorms tonight, especially later in the night, through Saturday. A surface boundary and weak wave along it will remain to our south. Once the system passes to our east, rain chances will end from west to east Saturday afternoon and evening. Used cooler raw model output temperatures as a guide Saturday given the clouds and rain. Overall QPF from anywhere from 1/3-3/4", higher amounts south. Considerable clouds through Saturday, decreasing Saturday night. .LONG TERM...(Sunday through Friday) Issued at 250 PM CDT Fri May 3 2019 Average confidence in the extended with synoptic scenarios. There continues to be timing issues with the start and end of precipitation next week. Will likely have to go with a blend solutions with a little better agreement that previous runs. The GFS is probably the fastest or most aggressive at bringing precip into parts of the area earlier next week with ECMWF a little slower and the Canadian yet the slowest. They all agree on high pressure dominating the weather pattern Sunday with dry conditions and the start of a warming trend. The high will slowly drift toward the east coast early in the week. As it does the flow at the surface will become more southerly. This will not only help start a warming trend but it opens up the gulf and dew point rise. In the upper levels a spoke of energy is ejected out the main trough over the southwest...which has a closed low which is slow to move due to that fact. This will be the first of several spokes of energy to eject from southwest upper low from mid to late week. There will also be slow moving cold front That will move into the area late Wednesday and slowly move through Thursday as well. This front looks as if it may stall just south of the area by Friday. It should however scour out the moisture and bring temperatures back to near normal. We will have to monitor this closely since it will be in close proximity to the area. We may be fortunate enough to have a dry weekend but its too far out for any degree of certainty at this early date. && .AVIATION... Issued at 638 PM CDT Fri May 3 2019 MVFR ceilings over much of the region may erode a bit from the southeast this evening, before returning later tonight as another round of showers overspreads the area. As the showers set in, IFR or lower ceilings are expected with MFR to occasional IFR visibilities. Conditions should improve from west to east in the afternoon, as the showers come to an end. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ UPDATE...DRS AVIATION...DRS