Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/13/18

Area Forecast Discussion
National Weather Service Boston/Norton MA
1104 PM EDT Fri Oct 12 2018 .SYNOPSIS... Dry cool conditions will push across the region overnight as the remnants of once Hurricane Michael tracks toward Newfoundland. A low pressure trough pushing quickly east will result in a period of chilly showers Saturday morning, with a drying trend to follow in the afternoon. Dry pleasant weather returns Sunday. A cold front will bring mild temperatures Monday along with numerous showers late Monday into Monday night, possibly lingering into early Tuesday morning. Behind the front, a drying trend along with seasonably cool weather later Tue into Wed. A brief trend toward noticeably cooler conditions is on track for Wed night into Thursday. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... 1020 PM Update... More high clouds stream quickly E across the region as seen on the latest GOES-East Air Mass RGB satellite composite. Even with the high thin clouds, temps have been slowly but steadily falling over the last few hours, with some readings down to the lower-mid 40s at some of the normally cooler locations at 02Z. Some lower clouds have worked into N central/NW Mass. With the open, fast flow aloft, will see more clouds push across the region as another quick moving H5 short wave shifts eastward out of the Ohio Valley and Great Lakes. Previous forecast pretty much on track, so only updated near term to bring conditions current. Previous Discussion... Dry cool air continues to pour into the region via NW flow aloft. SPC meso analysis already has the 0C isotherm at 850 mb entering western MA. This will set the stage for a round of chilly showers tomorrow morning. Progressive pattern already bringing showers into the OH valley this evening. Latest Hi Res guidance including the HRRR have these showers entering western MA/CT 5 am to 6 am and then overspreading RI and eastern MA by 8 am to 9 am. Again with cold air aloft advecting across the area tonight will result in chilly showers tomorrow morning. The good news is this system will remain progressive so a drying trend develops during the afternoon along with some breaks of sunshine. Previous forecast captures these details so no major changes with this update. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/... A period of instability showers is expected to continue through the morning across much of southern New England, than diminishing from W to E during the late morning into the afternoon. Not expecting a washout. Compared the the rain portions of our region saw earlier today, this rainfall will be a comparative drop in the bucket, generally amounting to less than one quarter inch, where it rains at all. Drier and even colder weather arrives Saturday night. Temperatures will be well below normal Saturday, with most locations stuck in the 50s, with some 40s across the higher terrain. Clearer skies with light winds Saturday night will set the stage for potential frost. Frost Advisory headlines may be needed for a portion of southern New England Saturday night, mainly across the higher terrain of northern MA. && .LONG TERM /SUNDAY THROUGH FRIDAY/... 345 PM update... .Highlights... * Sunday pick of the weekend * Showers likely late Mon/Mon night * Then coolest air of the season mid to late next week Synoptic Overview & Model Preferences... Ensembles and deterministic guidance in good agreement this period with two distinct large scale features of interest. First is the reemergence of the subtropical ridge over the southeast states early next week. This initially tempers northern stream intrusions of cooler air into southern New England with post frontal airmass only yielding seasonable temps. Second feature of interest is building eastern Pacific/western Canada ridge which eventually delivers an unseasonably cool airmass into New England in the Wed/Thu time frame. Given model spread is small will follow a model blend this period but incorporate some of the warmer EC mos guidance for the prefrontal airmass Monday where EC mos tends to verify better. Also for radiational cooling conditions Sunday night and possibly again Tue night will blend in the cooler MOS guidance. Sunday... Looks to be the pick of the weekend as short wave ridging advects across the area. 1024 mb high moving across the region provides a light westerly flow. Thus sunshine and light winds will result in very pleasant conditions. 925 mb temps about +6C. Model soundings suggest mixing to about 875 mb. This combined with westerly flow in the blyr should support highs 55-60. Then cool Sunday night as high pres crest over the region. As mentioned above will side closer to the cooler MOS guidance for lows Sunday night. Monday... The day probably begins dry but increasing clouds given WAA ahead of next trough and attending cold front. Showers likely during the afternoon and/or evening. Typical timing difference at this time range with GFS/GEFS faster than the EC/ECENS. Strong low level WAA with NAM/GFS/EC pushing 925 mb temps to +14C late Monday here. However clouds and showers will temper highs in the 60s. Tuesday... Post frontal airmass should overspread the region, so other than a low risk for showers early across southeast MA from departing cold front, trending the forecast dry and seasonable. Could turn out to be a fairly nice afternoon by mid Oct standards. Wednesday/Thursday... Potent northern stream short wave approaches the region mid week. At this time range it appears to be a mainly dry frontal passage but given the amplitude of the trough a fairly robust surge of CAA with both ECENS and GEFS ensembles offering -6C 850 temps Thu. Deterministic 12Z GFS and EC as you would expect are a bit colder at -8C at 850 mb 12z Thu. Thus coolest air of the season most likely with temperatures running about 10 degs cooler than normal Thu. Depending on the exact timing of the FROPA, Wed could turn out to be a dry seasonable day. && .AVIATION /03Z SATURDAY THROUGH WEDNESDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 0245Z update... Short Term /through Saturday Night/...High confidence in trends. Moderate confidence in timing. Overnight...High confidence. VFR conditions continue through around 04Z or so. Will see areas of MVFR-IFR CIGS/VSBYS move in from W-E through the early morning hours. A weak trough will bring scattered showers and patchy fog. Saturday...VFR. Brief MVFR cigs/vsbys possible, mainly inland in scattered SHRA. Saturday Night...VFR. KBOS Terminal...HIgh confidence in TAF. KBDL Terminal...High confidence in TAF. Outlook /Sunday through Wednesday/...High Confidence over the Sunday through Sunday Night: VFR. Monday: Mainly MVFR, with areas VFR possible. Windy with gusts to 35 kt. Chance SHRA. Monday Night: Mainly VFR, with areas MVFR possible. Windy with gusts to 35 kt. Chance SHRA. Tuesday through Tuesday Night: VFR. Breezy. Wednesday: VFR. Windy with gusts to 30 kt. && .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. 03Z Update... NW winds will continue to diminish across the coastal waters overnight. Small Craft Advisories will continue through the night across the open waters as well as RI/BI Sounds, mainly for rough seas. Good visibility expected through midnight or so. Showers will approach the waters toward daybreak Saturday, continuing through midday then will push offshore. May see locally reduced visibility to about 3 NM for a brief time in some heavier showers and patchy fog. W-NW winds 10-15 kt with gusts up to 20 kt into Saturday afternoon. W-NW wind gusts increase to around 25 kt again Saturday night. Good visibility. Outlook /Sunday through Wednesday/...High Confidence. Sunday through Sunday Night: Winds less than 25 kt. Monday: Low risk for gale force winds with gusts up to 35 kt. Areas of seas approaching 5 ft. Chance of rain showers. Monday Night: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Seas up to 5 ft. Chance of rain showers. Tuesday: Low risk for Small Craft Advisory winds with gusts up to 30 kt. Areas of seas approaching 5 ft. Tuesday Night: Winds less than 25 kt. Wednesday: Low risk for gale force winds with gusts up to 35 kt. Local rough seas. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 7 AM EDT Saturday for ANZ235-237. Small Craft Advisory until 11 AM EDT Saturday for ANZ250-254. Small Craft Advisory until 1 PM EDT Saturday for ANZ255. Small Craft Advisory until 9 AM EDT Saturday for ANZ256. && $$ SYNOPSIS...Belk/Nocera NEAR TERM...Nocera/EVT SHORT TERM...Belk LONG TERM...Nocera AVIATION...Belk/Nocera/EVT MARINE...Belk/Nocera/EVT
Area Forecast Discussion
National Weather Service Grand Rapids MI
934 PM EDT Fri Oct 12 2018 LATEST UPDATE... Update .SYNOPSIS... Issued at 330 PM EDT Fri Oct 12 2018 Below normal temperatures will stick around through at least the middle part of next week, with several chances for frost or freezing temperatures at night. Widespread cold rain will impact southern Lower Michigan this evening, and another rain event will impact the entire area on Sunday night. && .UPDATE... Issued at 934 PM EDT Fri Oct 12 2018 My current plan is not to change our frost/freeze headlines and allow this to play out tonight. As for the showers, the lake enhanced shower event continues to occur thanks to 850 temps ranging from -6c near Ludington to -3c by South Haven. The coldest pocket of low level temperatures is currently crossing Lake Michigan. Until the axis of cold advection comes through (before midnight) the showers will continue. After that passes inland the showers will diminish and end (likely in the midnight to 3 am time frame). Getting back to the frost/freeze headlines, once the axis of cold advection is through the clouds should start breaking up. This idea continues to be supported by the HRRR, RAP and NBM. I do admit it seems the clearing will be in the 3 am to 5 am time frame. Still, it is possible given how cold it is now with the clouds and rain showers, we could yet see lows below freezing in our northern counties. It would seem the area west of US-131 and south of Grand Rapids will have clouds the longest and that will be the least likely area to see a frost. Still, it seems better to give the forecast a chance to work so I will not change our headlines. && .DISCUSSION...(This evening through next Friday) Issued at 330 PM EDT Fri Oct 12 2018 Will issue a Frost Advisory for the entire area tonight, although a Freeze Warning will be posted for the area from roughly Fremont to Mt Pleasant northward. We have a shortwave passing through this evening that brings clouds and rain (best pops south of I-96), but that moves out quickly later this evening. Subsidence behind the shortwave will clear the skies quickly overnight and winds will subside with the arrival of the sfc ridge, creating an ideal setup for frost and freezing temperatures. Some uncertainty still exists on timing/extent of clearing tonight, especially near Lake Michigan where lake clouds may linger all night. Debated leaving out the southwest corner, but inland portions of those coastal counties still have a decent frost risk so decided it was best to include everyone. While mostly sunny skies are expected on Saturday, the winds will be increasing out of southwest as the sfc high center passes by to our south. This will lead to brisk conditions developing by afternoon with wind gusts to 25 mph. Guidance is in good agreement on another widespread rain on Sunday night ahead of next upr trough dropping in from the northwest. If the clouds do not thicken up until later in the day and the rain holds off until nighttime, we could potentially have highs Sunday near 60. Considerable lake effect clouds and showers will follow on Monday with highs only in the 40s behind that system with the next push of cold advection. Yet another trough drops in from the northwest on Tuesday, which ushers in another reinforcing shot of cold air for mid week. Models have been suggesting a brief mild spell moving in for the end of next week with highs back up near 60 or above as upper troughing temporarily lifts out, but confidence low at this time. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 750 PM EDT Fri Oct 12 2018 As another pocket of cold air moves in behind this latest system some lake enhanced showers have developed. There is an area of MVFR/IFR cigs along the I-94 TAF sites, were there was several hour of light rain this afternoon. However, there is a push of dry air over WI heading this way. We are still thinking skies will clear between 06z and 09z, and once skies do clear they should stay that way till tomorrow night when more clouds move in. I will admit I am not 100 percent on the sky actually clearing overnight, if nothing else ceilings should become VFR at all sites by 09z or so. It should be noted there has been some mixed icing reported in the clouds during the past hour. The freezing level is near 2500 ft agl so if you are in the clouds likely you will have some icing this evening. && .MARINE... Issued at 330 PM EDT Fri Oct 12 2018 Although winds and waves will briefly subside late tonight early Saturday with the arrival of surface riding, they quickly crank up again out of southwest. We have therefore extended the small craft Advisory through Sunday afternoon. && .HYDROLOGY... Issued at 153 PM EDT Fri Oct 12 2018 Rivers have begun to stabilize and gradually fall after steady rain on Wednesday led to rising water levels near or over bankfull for some rivers. Weak showers may return to southern Michigan this afternoon and again on Sunday, but no significant rainfall is expected for the area. Rainfall amounts in the next week are expected to remain limited, therefore continued falling water levels into the start of next week is expected. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Frost Advisory from 2 AM to 9 AM EDT Saturday for MIZ037-043- 050>052-056>059-064>067-071>074. Freeze Warning from 2 AM to 9 AM EDT Saturday for MIZ038>040- 044>046. LM...Small Craft Advisory until 4 PM EDT Sunday for LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...Meade DISCUSSION...Meade AVIATION...WDM HYDROLOGY...ANH MARINE...Meade
Area Forecast Discussion
National Weather Service Lincoln IL
912 PM CDT Fri Oct 12 2018 .UPDATE... Issued at 912 PM CDT Fri Oct 12 2018 Light rain still occurring in some areas of the CWA this evening and based on radar, appears this will continue in the east this evening little longer. So update to the forecast will be forthcoming to better reflect current trends of precip in CWA. Will have to make some adjustments to the cloud cover as well given current satellite trends. && .SHORT TERM...(This evening through Saturday) ISSUED AT 256 PM CDT Fri Oct 12 2018 Short-wave trough evident on 19z/2pm water vapor imagery over western Iowa continues to provide the necessary synoptic lift for widespread cloud cover and light precipitation across central Illinois this afternoon. Where precipitation has occurred, ample evaporational cooling of the previously dry boundary layer has dropped temperatures into the middle to upper 30s. As a result, have observed snow or a rain/snow mix at times along and north of a Rushville to Lincoln line. The precipitation area will continue working its way eastward across the area and is expected to end from northwest to southeast early this evening as the short-wave passes overhead. Big question for later tonight will be whether or not skies clear in the wake of this feature. Model solutions vary greatly, with some CAMs suggesting clearing skies overnight and others keeping conditions mostly cloudy. Upstream satellite imagery shows plenty of clouds across Iowa into eastern Nebraska. In addition, with high pressure sliding overhead and very little wind tonight...would tend to think low-level moisture will essentially become trapped. NAM forecast soundings support this as they show a persistent pinch of moisture at around 925mb through Saturday morning. HRRR ceiling forecast hints that clouds will gradually scatter this evening, then low clouds and/or fog will re-develop overnight. Have therefore gone with a more pessimistic forecast of partly to mostly cloudy skies tonight. Low temperatures will drop into the middle 30s, but with cloud cover likely hanging around, have opted not to issue a Frost Advisory. Cloud cover will dissipate by midday Saturday, followed by a mostly sunny afternoon with highs reaching the lower to middle 50s. .LONG TERM...(Saturday night through Friday) ISSUED AT 256 PM CDT Fri Oct 12 2018 Moisture from former Pacific Hurricane Sergio will stream across the Ozarks into the Ohio River Valley Saturday night, but will remain south of the KILX CWA through Sunday morning. Meanwhile, a strong northern-stream wave will begin diving southeastward out of Canada. This particular wave will help draw the Sergio moisture northward by Sunday afternoon/night, during which time likely PoPs for rain will be warranted across the board. As the northern stream wave digs into the Great Lakes, it will push a cold front through central Illinois late Sunday night into Monday morning. Light rain will linger ahead of the front across the E/SE CWA into Monday morning before exiting into the Ohio River Valley by afternoon. High pressure building into the Midwest behind the front will bring the coldest weather of the fall season thus far, with lows Monday night dipping into the upper 20s and lower 30s. Frost/Freeze headlines will likely be needed at that time. After that, a cool/dry pattern will be in place across the region through the end of the week. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 639 PM CDT Fri Oct 12 2018 IFR/LIFR conditions should prevail at sites tonight and probably overnight as low level RH and resulting cloud cover gets trapped under an advancing high pressure sfc ridge. Some models show clouds dissipating overnight and toward morning hours, while Bufkit data shows cloud cover continuing through late morning. Will lean toward the pessimistic side and keep IFR clouds at all TAF sites overnight with conditions improving to MVFR tomorrow morning and then continuing into the afternoon. Winds will be light and variable through the night and then become southerly tomorrow morning through afternoon. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Auten SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Auten
Area Forecast Discussion
National Weather Service Omaha/Valley NE
621 PM CDT Fri Oct 12 2018 .SHORT TERM...(Tonight through Monday) Issued at 150 PM CDT Fri Oct 12 2018 Very changeable weather through the weekend, which will include warming temperatures Saturday ahead of a cold front, some rain mixed with snow Saturday night into Sunday, and then a hard, killing freeze Monday morning. Area of rain moving through the area is winding down this afternoon, and should be over by early evening. The HRRR models suggest that a few lingering sprinkles could be occurring in east central NE and northwest IA early this evening, but they are perhaps a couple of hours behind based on recent radar imagery. Thus any outdoor games tonight should be dry, and cold. Overnight lows tonight in the upper 30s to around 40. On Saturday, we do get a brief warmup with southerly flow ahead of a cold front, which arrives during the afternoon. Models are in good consensus in developing scattered showers along the front which continue through the night. Colder air moving in behind the front could allow precip to mix with or change to snow in northeast NE after midnight. Temperatures will continue to fall Sunday morning, with a rain/snow mix spreading southward through the forecast area. Temperatures fall far enough that it may become all snow south of I80 by late morning and during the afternoon, with temperatures in the lower 30s. Along and north of I80, where moisture isn`t as deep, we may see some slight recovery of temps in the afternoon into the upper 30s, which would also help to melt any snow that fell during the morning, and keep any lingering precip a rain/snow mix. Along/north of I80, we have less than 1/2" possible Saturday night into Sunday, but we do have 1-2" possible in southeast NE and extreme southwest IA where temps don`t have a chance to recover, and precipitation would be heavier and snowfall for a much longer periods. Rain/snow mix lingers south of I80 Sunday evening, then ends. Then, the coldest air of the season spreads over the area Sunday night. Temps drop into the mid to upper 20s by daybreak Monday, resulting in a hard, killing freeze for the entire area. We will likely issue a freeze watch for this within the next day, and this would also end the growing season for the local area. Highs Monday still pretty chilly in the lower 40s with dry conditions. .LONG TERM...(Monday night through Friday) Issued at 150 PM CDT Fri Oct 12 2018 The extended forecast will be characterized by dry weather and gradual warming temperatures. Highs Tuesday in the lower 50s, but eventually reaching the lower 60s by Friday. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 610 PM CDT Fri Oct 12 2018 VFR conditions will prevail thru the fcst pd. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ SHORT TERM...DeWald LONG TERM...DeWald AVIATION...DEE
Area Forecast Discussion...UPDATED
National Weather Service San Angelo TX
948 PM CDT Fri Oct 12 2018 .UPDATE... Indications this evening from the HRRR and RAP short-range models, and now the 00Z NAM, are for the remnants of former tropical system Sergio to have a track farther south across our northern and central counties. The east-west surface boundary continues to sag south and should stall somewhere across the central part of our area. With these indications and the associated threat for heavy and possibly excessive rainfall, we have extended the Flash Flood Watch farther south to include the Concho Valley and Heartland areas. This includes the cities of San Angelo, Brownwood and Brady. The Flash Flood Watch now begins at 11 PM tonight and continues through 1 PM on Saturday. Rain chances have been increased across the Flash Flood Watch area, and the updated forecast products have been sent. && .PREV DISCUSSION... /issued 701 PM CDT Fri Oct 12 2018/ AVIATION... /00Z TAFS/ Initially this evening, scattered showers and a few thunderstorms are occurring south of I-20 and north of a line from Mertzon to San Angelo to Brownwood. A weak cold front, with a roughly east- west orientation, is just south of I-20 and drifting south. This front should stall just north of San Angelo tonight. Winds will be south to southeast tonight at all of our TAF sites except KABI, where winds will be from the northeast or east-northeast. Scattered showers and a few thunderstorms are expected until late tonight, when the remnants of former tropical system Sergio arrive from the west. Widespread coverage of showers and a few thunderstorms is expected across the northern third to half of our area late tonight and Saturday morning. The coverage of showers and storms will be considerably lower farther south. Prior to the arrival of this convection, ceilings should drop into the MVFR range early tonight. Ceilings late tonight through much of Saturday morning are expected to be 800-1500 ft. Visibility reductions are expected in heavier rain with the showers and thunderstorms. Overall conditions will improve from west to east on Saturday afternoon, as most of the showers and thunderstorms move out of our area. Some isolated to scattered redevelopment of showers and thunderstorms will be possible, mainly across the eastern Big Country and south to Brady and Richland Springs. Winds at KABI will become south-southwest by early Saturday afternoon, and then shift to northwest. For our other TAF sites, increased and gusty south to southwest winds are expected on Saturday afternoon. 19 PREV DISCUSSION... /issued 257 PM CDT Fri Oct 12 2018/ SHORT TERM... (Tonight and Saturday) .Flash flood watch for the Big Country late tonight through early afternoon.... Remnants of Sergio are expected to move quickly northeast across West and north Texas late tonight and Saturday. The best potential for heavy rainfall will be north of a surface low as it moves northeast...along and north of I-20 in the Big Country. While the main threat from the storms will be heavy rainfall, there is a slight to marginal risk for severe storms, including the potential for an isolated tornado. The system will be quick moving, with the surface low moving northeast of the region Saturday afternoon, along with decreasing rain chances. Gusty southwest to west winds are expected late morning into the afternoon as the surface low moves northeast. Highs in the upper 70s to lower 80s are expected south of I-20 Saturday with clearing skies and and downslope westerly winds. 04 LONG TERM... (Saturday Night through Friday) Still looking like a lull in the rainfall Saturday Night into Sunday morning with Sergio racing away from the area. Next round of showers and thunderstorms will develop for Sunday and Monday as the strongest cold front so far this season arriving across West Central Texas. As usual, the NAM is much faster than the GFS and with these type of air masses, the faster frontal progress is usually a better solution. As the front moves into the area, showers and storms will become widespread once again for Sunday afternoon into Sunday Night and Monday Morning. Another 1-3 inches of rain expected Sunday into Monday, and Flash Flood Watches may well be needed for much of West Central Texas once again. Front pushes well south by Sunday Night, with an upper level low closing off across the Southwest US for early next week. This produces an overrunning situation north of the front, so expect a moderate to occasionally heavy rain at times to develop across the area at time through at least mid week. Temperatures will be unusually cold Sunday Night and Monday behind the front. Temperature records are likely to fall at both Abilene and San Angelo, both for record lows as well as coldest high temperatures. Some moderation in temperatures begins on Tuesday but will stay below normal levels. 07 && .PRELIMINARY POINT TEMPS/POPS... Abilene 64 75 59 71 / 90 90 20 70 San Angelo 66 83 62 75 / 90 90 20 60 Junction 70 84 67 78 / 50 60 20 50 Brownwood 66 79 63 78 / 80 90 20 70 Sweetwater 62 70 58 69 / 90 90 20 60 Ozona 68 82 64 78 / 60 60 20 50 && .SJT WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through Saturday afternoon for Brown-Callahan- Coke-Coleman-Concho-Fisher-Haskell-Irion-Jones-McCulloch-Nolan- Runnels-San Saba-Shackelford-Sterling-Taylor-Throckmorton-Tom Green. && $$