Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/17/19


AREA FORECAST DISCUSSION
National Weather Service Albany NY
1009 PM EDT Sat Mar 16 2019 .SYNOPSIS... Breezy conditions with cooler temperatures under mostly cloudy skies along with a passing rain or snow shower. Conditions will slowly improve through the remainder of the weekend as seasonably cool weather will persist into early next week as an upper trough controls the weather. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... As of 1010 PM EDT, only minor changes made to the hourly pops and temps to reflect recent obs. Further details regarding the near term forecast follow... As of 730 PM EDT, with loss of daytime heating/mixing, cloud cover is decreasing with the exception of downwind locations from the lakes. Snow shower activity has also decreased but will remain possible across portions of the western Dacks and Mohawk Valley through this evening. Based on current trends, have adjusted hourly sky cover, pops and temps. The remainder of the forecast remains on track. Prev Disc... As of 400 PM EDT...Brisk conditions remain under ample stratus across the region as we increased cloud coverage with this update across most of the region. Temperatures have likely achieved their maximum potential with perhaps another degree or two as cold advection continues across the region. Some lake effect rain and snow showers will remain as regional radar and trends continue to favor the higher terrain and portions of the western Mohawk Valley. More of the same tonight, although the pressure gradient relaxes somewhat, allowing for winds to diminish (but still stay elevated). Lowering inversion heights should allow lake effect snow to decrease in coverage. Hires NAM and HRRR suggest a couple bands of snow will impact portions of the Dacks, Schoharie Valley and eastern Catskills overnight as another mid-level front moves in from the north and lake effect downwind of Lake Ontario persists with backing winds. Lows in the teens and 20s will be near normal, but wind chills will be in the single digits and teens. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... Pre the previous AFD, a broad longwave trough continues to dominate the weather through the short term. H850 temps averaging 1 to 2 standard deviations below normal per the GEFS. The pressure gradient continues to relax, so while there will still be an elevated westerly breeze, it will be considerably weaker through the short term period. Any lingering lake effect activity should diminish early Sunday as inversion heights get squashed, and a mix of sun and clouds is expected (most of the cloud coverage across the higher terrain). Still cool for this time of the year with mainly 30s and 20s across the higher terrain. Sunday night into early Monday, a shortwave trough will pivot into the region that originates from north-central Canada and northern Mississippi River Valley. Best moisture profiles remain disjointed as downstream mid level flow remains confluent so a weakening trend should commence. Regardless, NCEP model suite supports a compact surface wave to develop well to our south with its precip shield also remaining to our south. A few flurries or light snow remains an outside chance as we will continue with the slight chance PoPs to the areas well west and south of Albany. Seasonably cold Sunday night with lows mainly in the teens to mid-20s. Monday may be a couple degrees warmer than Sunday, but still around 5F below normal. High pressure begins to expand into the region Monday and Monday night with improving sky conditions with light winds yet still cool temperatures for the mid-March period. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Temperatures for the upcoming long term period will be cool at the start, ranging 5-10 degrees below normal, before we moderate back towards normal by mid-week but look to cool down again heading into the weekend. We enter into a split flow pattern by the middle of next week with active northern stream and southern stream shortwaves to monitor. While there are still some discrepancies among the latest global guidance, the track and intensity of each shortwave is starting to come into better alignment than previous runs. Thus, we continue the mention of rain and snow showers for the Wed - Thurs time period. Read on for details. We start the long term period on Tuesday with a trough moving through the Northeast and a strengthening surface high pressure from the Ohio Valley pushing eastward. Since the trough axis does not exit eastern NY and western New England until closer to 18z Tuesday, we lingered cloud coverage through the morning hours. With northwest flow ushering in 850mb isotherms near -12C to -14C plus delayed sunshine, Tuesday should be the coolest day of the week. We adjusted temperatures downward with highs only reaching into the 30s for most areas which is 5-10 degrees below normal. Subsidence in the wake of the trough axis combined with the building surface high pressure should lead to increasing sunshine during the afternoon hours with mostly clear skies and calm winds overnight. This should lead to radiational cooling and another chilly night with lows falling into the teens (single digits Adirondacks/Greens) by early Wednesday morning. Our 1030-1035hPa high should be in control of the Northeast for Wednesday giving us mostly sunny skies with seasonable temperatures in the mid - upper 40s. Clouds look to gradually increase late in the day ahead of a northern stream shortwave swinging into the Great Lakes. As our surface high shifts eastward Wednesday night, we should see a return southwesterly flow ensue which should keep temperatures steady overnight in the mid 20s to low 30s. At this point in the forecast period, we will be closely monitoring the aforementioned northern stream shortwave in addition to a southern stream wave in the Mississippi Valley. While the GFS in previous run showed a more robust northern shortwave leading to a clipper tracking through the Northeast, it has trended a bit weaker in the latest run but still suggests an organized area of rain/snow showers moving through the area Thursday into Friday. The ECMWF has trended closer to this solution with its QPF field resembling that of the GFS. The CMC-NH remains the driest solution which is likely due to it intensifying the southern stream shortwave much more than than the ECMWF and GFS which leads to downstream subsidence over eastern NY/western New England. For now, we continued to mention chance POPs for areas north of I-90 and slight chance south of I-90 for this period. Daytime temperatures look mild enough to support rain mixed snow showers in the terrain with all rain in the valley, overnight temperatures could cool enough that mixed showers could become snow, again mainly in the higher terrain. The ECMWF and the CMC-NH show our southern stream shortwave quickly intensifying off the Carolina/mid-Atlantic coast late in the week into a notable coast storm and with our northern stream shortwave diving down into the Northeast, we will have to monitor if any phasing takes place. At this point, the guidance agrees that our southern stream wave outruns the northern stream energy which means any phasing impacts should be limited to eastern New England. Still worth monitoring in future updates. The northern stream shortwave amplifies as it progresses through the Northeast on Friday with a good surge of cold air advection arriving in the wake of the surface cold front and upper level trough axis. This should lead to a quick cool down and breezy conditions Friday afternoon into Friday night. Strong northwest flow will continue to usher in chilly Canadian air heading into Saturday which lead to below normal temperatures for the first half of the weekend. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... Breezy and cold weather will persist through 24 hour TAF period ending 00Z Monday. VFR conditions expected to prevail at the terminals, with perhaps a snow shower at KALB/KPSF for the next hour or two. With a cyclonic northwest flow regime in place through the period, SCT to BKN cigs will generally prevail. However, some downsloping should result in less cloud cover at KPOU especially tonight into Sunday. West-northwest winds around 13-18 kt with gusts of 25-35 kt will persist this evening, then winds speeds decreasing to around 9-13 kt with gusts up to 25 kt tonight. Outlook... Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA. && .FIRE WEATHER... Westerly winds will gust over 25 mph on Sunday... Breezy conditions continue into Sunday with 25-30 mph at times. Temperatures will return to seasonable values with partly cloudy skies for valley areas, and mostly cloudy skies and some light snow showers for the higher terrain mainly west of the Hudson. RH values outside of the higher elevations where there is snowpack will fall to the 30 to 50 percent range Sunday and Monday. && .HYDROLOGY... Mild temperatures yesterday resulted in snowmelt and allowed river levels to rise modestly, although no flooding occurred. Most valley locations have lost the snowpack, but snow depths in excess of a foot are still being observed over the southern Adirondacks and southern Greens. Temperatures will return to near to below normal today into early next week, which should shut off most of the snowmelt. Some slower-responding rivers may continue to rise today before leveling off, while other rivers will begin to fall. Hydrologically significant precipitation is not expected through at least the middle if not the end of the upcoming week. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...BGM NEAR TERM...BGM/JLV SHORT TERM...BGM/Thompson LONG TERM...Speciale AVIATION...JPV/JLV FIRE WEATHER...BGM/Thompson HYDROLOGY...BGM/Thompson
Area Forecast Discussion
National Weather Service La Crosse WI
1000 PM CDT Sat Mar 16 2019 .SHORT TERM...(This evening through Sunday night) Issued at 245 PM CDT Sat Mar 16 2019 Dry northwesterly flow will continue through the rest of the weekend with an established longwave trough centered across the Great Lakes. Water vapor imagery early this afternoon showed a shortwave trough to the west swinging eastward out of the Dakotas with several additional waves upstream set to rotate southeastward through the rest of the weekend. The shortwave to the west will interact with the mid-level baroclinic zone to produce a band of light snow that will mainly impact areas to the south across parts of Iowa and Illinois this afternoon/evening, with little impact to the local area. With light winds overnight, could not rule patchy fog development, although increasing clouds could be a limiting factor for fog. Cyclonic flow aloft along with steep low level lapse rates on Sunday will result in a cloudier day with a few flurries/sprinkles possible. Fairly neutral temperature advection is expected through the weekend so highs on Sunday once again look to be in the 30s to low 40s. .LONG TERM...(Monday through Saturday) Issued at 245 PM CDT Sat Mar 16 2019 A generally quiet period is expected for much of the coming week. Throughout the course of the work week, an amplified upper level ridge will gradually translate eastward from the western US into the plains by late week. As this occurs, airmass recovery will occur through the week. Temperatures will begin the week below average with highs in the 30s to around 40 on Monday, recovering to the 40s to near 50 by mid-week, and likely well into the 50s for many locales by late in the week. Precipitation chances through the week will be low. An upper trough will drop south from the Canadian prairies on Tuesday with a weak surface cyclone moving from the central plains towards the lower Great Lakes through Wednesday. The 16.12Z ECMWF/GEM remain farther west with the upper trough compared with the GFS. However, either way, model consensus suggests the highest precip chances will be south of the area. Beyond mid-week, broad surface high pressure will keep the area dry late this week into the start of the coming weekend. && .AVIATION...(For the 06Z TAFS through 06Z Sunday night) Issued at 1000 PM CDT Sat Mar 16 2019 Cigs/wx/vsby: shortwave trough scoots just south of the TAF sites this evening, keeping cig/pcpn impacts south. Another shortwave moves in overnight, a bit farther north. This looks to bring some mvfr/ifr to KRST, with RAP now suggesting it could encroach upon KLSE toward 18z. Periods of flurries looking likely, but not as confident in -shsn and associated vsby impacts. Will keep any pcpn mention out of forecast for the moment. Wind: generally light (sub 10 kts) and from west to northwest though the period. && .HYDROLOGY... Issued at 245 PM CDT Sat Mar 16 2019 Minor to major flooding continues along area Mississippi River tributaries with record flooding continuing along the Trempealeau River at Dodge. Elevated water levels are expected to continue on the Mississippi River, with potential for minor flooding along a few portions of the Mississippi River into next week. However, water levels will remain below flood stage along much of the Mississippi River through next week. Snowmelt runoff will slow through early week with cooler temps, but warmer temps by late in the week will accelerate the snowmelt likely leading to further flood concerns. Please refer to the latest flood statements for additional details. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...JM LONG TERM...JM AVIATION....Rieck HYDROLOGY...JM
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
727 PM CDT Sat Mar 16 2019 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Coastal trough will continue to drive light to occasionally moderate northerly winds at the RGV aerodromes. Occasional light rain/showers are also expected as upper-level disturbances move by in fast flow aloft, mainly for BRO and HRL. Best chance of this appears to be between 09-15Z. Ceilings at MFE should remain VFR, though may drop to higher-end MVFR at BRO and HRL during times of precip. Can`t rule out a repeat of last night`s band of elevated showers with some embedded thunder moving across the RGV from the west/southwest (as suggested by recent HRRR model runs). However, not seeing any evidence of this over the upstream Mexican plateau at this hour, so will just continue to monitor. && .DISCUSSION...Updated for latest marine discussion below. && .MARINE...Latest report from Buoy 42020 is NNE winds at 16G19KT, with combined seas right around 7 feet. Buoy is also picking up on a longer-period (12-13 sec) swell due to the sustained NE fetch across the northwestern Gulf. Thus, have extended the SCA for the 20-60nm waters until 10 AM Sunday. Model guidance consistent in showing slightly lower wind speeds and wave heights over the nearshore waters, so have allowed the SCA to expire for those areas as of 7 PM. Regarding the coastal hazards, have opted to expire the High Surf Advisory as scheduled, as there is no evidence of wave heights greater than 6 feet in the surf zone, per web cameras on South Padre Island. Have extended the High Rip Current Risk and Coastal Flood Advisory another 24 hours, however. This is due to the aforementioned swell, as well as water levels very similar to where they were yesterday around this time (just touching 1 foot MHHW around high tide), so expecting similar impacts as predicted tides tomorrow very similar to today`s. && .PREV DISCUSSION... /issued 257 PM CDT Sat Mar 16 2019/ SHORT TERM (Tonight through Sunday Night): The H5 blocking feature remains stationary across the southwestern US, diverting the main storm track well into the northern plains, and pushing the southern jet across northern Mexico into south Texas. This keeps our flow from the southwest, with weak impulses sweeping through from time to time. These have increased lift briefly, allowing for more shower activity to form. At the surface, a trough remains offshore today, keeping keeping the area under dense cloud cover. Northerly winds continue to push colder air into the region, keeping temps around 60. Models are picking up on another midlevel wave racing through this evening, with elevated shower activity increasing as it approaches the coastal trough. Rainfall amount will remain light, due to the elevated nature of the showers and the speed they will be passing through. Coastal troughing will continue to produce modest northeasterly winds through the next 36 hours, continuing the coastal flood threat and rip current risk as wave action pushes ashore. High tides are currently mid-afternoon, with low tide occurring overnight. Coastal Flood Advisories and a high rip current threat continues today and tomorrow. LONG TERM (Monday through Saturday): The long term period will begin very similar to much of the short term period. Surface coastal troughing will keep cloudy and showery conditions across the region. At the surface, high pressure will move across the Red River Valley and into the Mid-South region through early next week. This will keep winds relatively light across the land zones. QPF doesn`t look too exciting with generally around a quarter of an inch expected through midweek, especially across the lower to middle valley with the least amounts in the upper Ranchlands. By midweek there will be a subtle pattern change. At the surface, winds will finally veer more east and southeasterly allowing for warmer air to advect into the region. We`ll need to watch for more marine fog as moisture rich and warmer air pushes over 65 degree sea surface temperatures. Aloft, the zonal flow is slightly interrupted by a subtle ridge axis that will intercept a frontal boundary moving southward into northern portions of TX by late Thursday. Eventually, another shortwave will slide east across the high plains by early next weekend helping push a cold front deeper into TX. Ahead of this front, expect showers and thunderstorms to increase. Unfortunately, although a pattern change is apparent, it doesn`t appear to be a drier pattern with QPF signals off and on throughout the long term portion of this package. As stated, at least temperatures will increase back closer to more seasonal averages. MARINE (Tonight through Sunday Night): North winds continue at 15 to 20 knots through the next 36 hours with the coastal trough remaining stationary offshore. Small Craft Advisories remain in effect for the Gulf waters through 7pm tonight. Seas have finally begun to relax some, but remain elevated at 5 to 6 feet. This modest onshore flow will continue through Sunday night, so small craft will likely need to continue to exercise caution through Sunday night. (Monday through Saturday): As moderate to strong northeasterly flow continues with the strong pressure gradient still situated across our marine zones, hazardous boating conditions will continue to start the long term marine period. In addition, showers will also be present. The moderate easterly fetch across the GOMEX will allow easterly swells to continue. Surface winds improve a bit (10 kts instead of 15kt), however, with the increase swells, cautionary wording or low end SCA is expected early next week. As pressure gradient and long easterly swells increase by midweek, hazardous marine conditions will again be likely to finish up the long term marine period. Also, can`t rule out marine fog developing again as surface winds shift to more easterly or southeasterly direction by midweek. Rainfall will be possible throughout the period as well with the possibility of thunder increasing late in the period. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...High Rip Current Risk through Sunday evening for TXZ256-257-351. Coastal Flood Advisory until 7 PM CDT Sunday for TXZ256-257-351. GM...Small Craft Advisory until 10 AM CDT Sunday for GMZ170-175. && $$ This product is also available on the web at: HTTP://WEATHER.GOV/RGV 53-Schroeder/56
Area Forecast Discussion
National Weather Service Lincoln IL
856 PM CDT Sat Mar 16 2019 .UPDATE... Issued at 856 PM CDT Sat Mar 16 2019 The shortwave is tracking into W-NW Illinois this evening, with precipitation rather spotty to this point, based on radar and upstream observations. The latest HRRR is indicated a limited period of snow showers for most of my CWA, and snow accums would likely be much less than the current forecast if that pans out. Will be pulling back a bit on snow amounts to trend in that direction. At this point, an inch in our far northern counties would be on the high side. At the very least, snow accums look less widespread than previous model runs. Temps look relatively mild as well, which works toward lower snow totals due to lower snow ratios. Updates this evening were mainly to PoP, weather, QPF and snow amounts. The remainder of the forecast looks on track. && .SHORT TERM...(This evening through Sunday) ISSUED AT 215 PM CDT Sat Mar 16 2019 Morning model suite has trended a bit north with our incoming disturbance, focusing the heavier snow axis a bit closer to I-80. Still looks close enough that the far northern CWA will see some minor snow accumulations overnight. Have increased PoP`s in that area, but decreased the snow totals except around Marshall and Stark Counties, which may see 1-2 inches. A light dusting may occur as far south as the I-74 corridor. A few flurries may linger into early Sunday from Peoria to Danville, but overall trend will be for dry conditions as the system quickly exits. Temperatures should still reach the mid- upper 40s, so any snow will quickly melt. .LONG TERM...(Sunday night through Saturday) ISSUED AT 215 PM CDT Sat Mar 16 2019 Longer range still looks to be largely quiet, with the only real concern being the system Tuesday night and Wednesday. Models are coming into better agreement with the sharpening wave dropping south out of the Dakotas, though the GFS does not close off a low over Missouri like the international models. Have kept the precipitation as all rain, with lows Tuesday night only in the mid-upper 30s. Heaviest rainfall amounts of around 1/3 inch should be roughly from Bloomington to Quincy, closer to the track of the surface low. The second half of the week continues to feature a nice warming trend, as upper level ridging builds into the central U.S. Expecting mid-upper 50s for Thursday and Friday, with 60 degrees as we start the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 658 PM CDT Sat Mar 16 2019 Satellite and radar images continue to track a fast moving shortwave over Iowa and headed toward the northern TAF sites. While VFR conditions expected to largely prevail through the period, there could be some periods of MVFR clouds and vis between 06z and 10z, if some of the snow showers increase in intensity. Low level thermal profiles point toward some rain at the onset, but a change to snow is being indicated in the soundings of the HRRR, RAP and NAM. PIA and BMI would be the primary recipients of the precip from this system, with CMI mainly in the flurries/sprinkles area. Winds will start out W-NW this evening, then become variable by mid-evening as low pressure passes across central IL. Winds will remain less than 10KT for the most part, as they become NE late tonight, then NW again tomorrow behind the low. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Shimon SHORT TERM...Geelhart LONG TERM...Geelhart AVIATION...Shimon