Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/07/19

Area Forecast Discussion
National Weather Service Goodland KS
455 PM MDT Sun Oct 6 2019 .SHORT TERM...(This evening through Monday) Issued at 155 PM MDT Sun Oct 6 2019 RAP 500 mb heights and water vapor show a weak upper disturbance pushing across the region today. As a result, some light rain showers moved through areas along the Nebraska border this morning and early afternoon. Around 2 PM MDT, northerly winds were at 10 to 15 mph, with occasional gusts up to 25 mph. Skies were clearing across the region as showers exited to the east. Temperatures ranged in the upper 50s to low 60s. Skies continue to clear from west to east the remainder of the afternoon. For Sunday night, surface high pressure is anticipated to move over the area, leading to light winds, clear skies and a drier air mass. These conditions will allow for temperatures to fall into the middle 30s across most of the region overnight/early Monday morning, making frost a concern once again. Have expanded the Frost Advisory to include the entire region. A lee side surface trough along the Front Range strengthens on Monday as the high pressure moves out. Winds turn to the south and filter warmer air into the area, with highs mainly in the low 70s under sunny skies. Relative humidities are forecast to fall between 15 and 20 percent for a couple of hours in the afternoon. South winds gusting around 25 mph make this a tough call, but it appears that conditions will fall short of meeting criteria for a highlight at this time. This will need to be monitored, and elevated fire weather conditions are anticipated along and west of the Colorado border Monday afternoon. Winds lighten some Monday night as temperatures fall into the upper 30s to upper 40s. .LONG TERM...(Monday night through Sunday) Issued at 304 PM MDT Sun Oct 6 2019 Synopsis: A busy long term period, with several nights of Frost Advisories expected, potential Freeze Advisory, and our first snow of the season Thursday Night. Tuesday, westerly flow aloft will prevail as the trough aloft exits our area. Warmer and dryer conditions will move in bringing our daily highs to the mid to upper 70s. Wednesday, flow aloft will begin to turn southwest ahead of a strong pacific NW trough located over Washington State. The system will not arrive until Wednesday night, so we will see daily highs once again climb up into the mid to upper 70s. Went with NBM at this time for the timing of the FROPA as guidance is still a little inconsistent with the arrival. At this time, introducing pops at 00Z Thursday. Rain will start off and our NW CWA will see some wintry mix going into the overnight hours. Rain, wintry mix, and snow chances will continue through Thursday and Friday mid-morning. Thursday and Friday we will see a wide varying gradient of daily highs and lows before the front makes it through the area. Both days will have highs from the low 30s to upper 40s, with overnight lows on Thursday night in the lower 30s to upper 40s, followed by Friday night lows in the upper teens to lower 30s. Come Saturday, after the system completely exits our area, ridging will begin to build back in over central Arizona. We will begin to warm back up with highs climbing to the 50s on Saturday and to the 60s on Sunday, with lows in the upper 20s to upper 30s each night. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 455 PM MDT Sun Oct 6 2019 For KGLD and KMCK, vfr conditions through the period. Light winds at taf issuance will continue the night with increasing south to southwest winds during the day Monday. Wind gusts to 25kts or so are expected. Winds subside and lose the gusts around 23z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Frost Advisory from midnight MDT /1 AM CDT/ tonight to 8 AM MDT /9 AM CDT/ Monday for KSZ001>004-013>016-027>029-041-042. CO...Frost Advisory from midnight tonight to 8 AM MDT Monday for COZ090>092. NE...Frost Advisory from midnight MDT /1 AM CDT/ tonight to 8 AM MDT /9 AM CDT/ Monday for NEZ079>081. && $$ SHORT TERM...JBH LONG TERM...EV AVIATION...99
Area Forecast Discussion
National Weather Service Wilmington NC
924 PM EDT Sun Oct 6 2019 .SYNOPSIS... High pressure will slowly shift off the coast this evening and overnight. A cold front will move east across the area early Tuesday, with seasonably cool and dry weather much of this week, accompanied by a slow drying and warming trend into the weekend. Another cold front will cross the coast Sunday. && .UPDATE... No significant edits were made with the evening updates. && .NEAR TERM /THROUGH MONDAY NIGHT/... High pressure ridging in from the NE US will give way during the period as a cold front moves in from the NW. With onshore flow, the approaching front and falling heights aloft as an upper trough moves into the area, rain chances will gradually increase during the period. Isolated showers will become more scattered Monday and Monday night with some potential for thunder. Lows tonight should fall to the low to mid 60s most areas with upper 60s nearer the coast. Highs Monday will reach the lower 80s with mins Monday night in the mid to upper 60s. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Cold front in the area Tue pushes offshore around midday or so with high building in from the north. Mid-level dry air spreads over the region Tue following the front, but low level moisture will linger. Skies will remain cloudy Tue with light rain/sprinkles lingering into the afternoon. Confidence is low as far as measurable rainfall goes, but certainly expect Tue to be damp. Highs Tue are tricky. Forecast soundings suggest wedge setting up with low clouds and drizzle Tue into Tue night and continuing Wed. A wedge would keep skies cloudy, limiting heating. Highs would occur early in the day, likely before noon, with temperatures falling in the afternoon. If clouds were to decrease, even slightly, highs could easily rise into the low 80s. Guidance continues to struggle with the strength of the wedge and will go in the middle of the NAM/GFS/EC solutions, with a slight nod to the cooler solutions. Front pushes farther off the coast Tue night into Wed, but the combination of lingering low level moisture and high wedging down the coast will keep skies cloudy, but rainfall chances will be limited. Highs will be right around climo, unless cloud cover is less than expected. Low temps each night will be near climo, helped by clouds and northeast winds. && .LONG TERM /THURSDAY THROUGH SUNDAY/... Brief mid-level ridging over southeastern Canada and New England mid to late week keeps 5h cutoff low lingering off the East coast through Sat. The resulting pattern aloft will maintain deep northwest flow aloft with low level north to northeast flow. Strength of northerly flow will be determined by strength of surface low under the 5h cutoff and the high building down the coast. Late in the week strong mid-level trough lifts from the west into the Great Lakes region, driving a cold front across the region Sun. Front is far displaced from the parent low and the lack of deep moisture suggests the front will pass dry. -Limited rainfall chances through the period due to lack of a deep moisture. -Temperatures near climo Thu rising above climo Fri and remaining above climo through Sun, warmest on Sat. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... The HRRR has been pretty consistent in bring in nocturnal showers from offshore. Very warm water will support this scenario, with a possible land breeze right at the coast. Expect MVFR conditions in the showers overnight. Monday, more showers are expected with low LFCs along the coast. Extended Outlook...Predominately VFR. Some light showers are possible on Monday and Tuesday, with MVFR ceilings again possible. Fog/stratus possible Wednesday and Thursday mornings. && .MARINE... E winds of 10 to 15 KT will become SE Monday and turn to the NE Monday night. Seas of 4 to 6 FT are expected through the period with the 6 footers expected in the SCA area northern waters. Northeast flow will dominate Tue through Fri with slow moving low pressure looping off the East coast. On Fri confidence in both the location and strength of the low is limited, but expect winds will back to more northerly as inland ridging weakens. Gradient starts to relax late in the week with speeds dropping under 15 kt Fri. Speeds will be 15 to 20 kt Tue through Thu with solid 20 kt possible Tue night through Wed night. Seas in the realm of Small Craft Advisory are possible Tue into Thu followed by a decreasing trend Thu and Fri. Northeast to east wind wave around 5 seconds will be the dominant wave feature with periods gradually increasing late in the week. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...Small Craft Advisory until 7 AM EDT Tuesday for AMZ250-252. && $$ SYNOPSIS...ILM UPDATE...8 NEAR TERM...RAN SHORT TERM...III LONG TERM...III AVIATION...43 MARINE...III/RAN
National Weather Service Wilmington OH
1019 PM EDT Sun Oct 6 2019 .SYNOPSIS... A cold front will slowly move southeast overnight. Precipitation will end from northwest to southeast Monday as the front continues to move away. High pressure will build into the Great Lakes Monday night. The high will then extend across the area into mid week. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... Cold front is located in the southeastern parts of the fa, running from Mason County KY up to Pike County OH. Thunderstorm activity appears to be limited to the vicinity of front. As the front continues to slip southwest overnight, so will the chance of thunder. Behind the front and thunderstorms is an area of showers. The backedge has worked to about the Ohio/Indiana border. Latest runs of the RAP and HRRR redevelop the activity around Louisville and lift it northeast across southeast Indiana later tonight. This will also help keep the PoPs high for locations farther east in the cwa. Still looking at temperatures falling into the lower to mid 50s tonight. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... On Monday, the mid level trough will cross our region. As this occurs, precipitation will gradually shift southeast and should exit our southeast zones during the afternoon. Surface high pressure will begin to build into the region from the west late in the day. Pcpn and lingering clouds will hold highs down in the southeast (upper 50s to around 60) while the northwest zones will being to see some filtered sunshine in the afternoon, which will result in highs in the upper 60s. For Monday night, the center of the surface high will build east into the Great Lakes. Drier air is expected to filter south and east along with clearing skies. Lows will fall into the lower to mid 40s. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Long term period will likely have an increasingly amplified pattern, with temperatures rising through the work week ahead of a deep surface low pressure system likely impacting sensible weather for the weekend. Low impact weather dominates Tuesday through Friday as surface high pressure ridge extends over the CWA from the high`s center to the northeast. As the high exits toward New England, low level flow shifts from the east on Tuesday around to a return southeasterly flow on Wednesday and Thursday. Temperatures will rise through this period from near normal on Tuesday to 6-8 degrees above normal by Thursday. Models continue to disagree somewhat for Friday/Saturday as a "temporary" blocking pattern sets up off the East Coast and an elongated upper level trough closes off over the northern Plains states. The development and position of the upper level low varies widely by deterministic model, and still is varying run- to-run for each model. This leads to differences in position of the associated cold front. On Friday, low level winds veer to the south ahead of tightening gradient, and in full warm air advection mode. The GFS pushes the cold front through the CWA early Saturday morning, providing a post-frontal Saturday with rain and temperatures falling through the 50s, while the Euro is still running a few hours behind. Another interesting note is that through the 06Z run, the deterministic GFS positioned the front well ahead of GEFS members, with most members lagging the thickness falls by 12-24 hours. Based on this, will trend slower with precip and temp falls as well. Models agree wind gusts in the cold air advection will be something to keep an eye on, so will do that. For now, deterministic runs through BUFKIT show 25-35 mph behind the front, but will trim that back a bit based on lower than normal confidence with timing. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... The tafs are now on the northside of the cold front and surface winds are generally from the north northwest. Showers and maybe a thunderstorm will affect the region this evening as upper level support associated with an advancing H5 s/w affects the area. Limited the mention of thunder to the srn tafs through 04Z, when the threat should work east of the tafs. During this time showers will affect all the tafs. As lower levels of the atmosphere reach saturation ceilings are expected to drop down to MVFR later this evening. KDAY is expected to stay VFR as it will be on the northern edge of the better pcpn. Between 09-12Z the deeper moisture will begin to be shunted eastward. This will allow drying to begin from west to east. Precipitation will also see a west to east trend, with the back edge of the precipitation moving through the I-71 corridor around 12-14Z. As all this occurs, ceilings will begin to rise, reaching VFR between 14Z and 18Z. While the low clouds dry out, some cirrus will linger through 18Z, when high pressure building in from the west, will scatter that out too. OUTLOOK...No significant weather expected. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...Hickman NEAR TERM...Sites SHORT TERM...Hickman LONG TERM...Hogue AVIATION...Sites
Area Forecast Discussion
National Weather Service Lincoln IL
651 PM CDT Sun Oct 6 2019 .SYNOPSIS... Issued at 238 PM CDT Sun Oct 6 2019 A cold front near the Ohio Valley, will cause unsettled weather to continue south of the I-70 corridor, into tonight. Farther north dry weather will prevail for central Illinois. The front will push well southeast of the area on Monday, as high pressure moves in. This high will provide dry and mild weather through mid-week. && .UPDATE... Issued at 651 PM CDT Sun Oct 6 2019 A short-wave trough noted on 2330z/630pm water vapor imagery over Nebraska/Kansas is producing a shield of mid-level cloudiness across central Illinois early this evening. Despite a very dry boundary layer, a narrow band of 35-40dBZ radar echoes along/east of the Illinois River has yielded sprinkles at a few ob sites. With HRRR showing this band shifting eastward with time, think a few sprinkles may be observed everywhere east of the Illinois River throughout the evening. Further south, a weak wave of low pressure tracking along a nearly stationary frontal boundary just south of the Ohio River will bring scattered showers to locations along/south of I-70. As the Nebraska/Kansas wave tracks eastward, skies will eventually clear across the Illinois River Valley shortly before midnight...then further east to a Danville to Taylorville line overnight. && .SHORT TERM...(This evening through Monday) ISSUED AT 238 PM CDT Sun Oct 6 2019 Cold front has stalled near the Ohio River this afternoon and will remain nearly stationary tonight as a shortwave lifts northeast into the Ohio Valley. This will cause frontogenesis north of the boundary, which will produce periods of showers south of I-70, into tonight. A few embedded thunderstorms are possible into early evening. After the shortwave lifts out the rain will diminish late tonight. Farther north, satellite imagery reveals a large area of mid to high level clouds, associated with a sheared shortwave and mid level trough axis over the upper Midwest. This area of cloudiness will continue shifting southeast, affecting the area through this evening and diminishing after midnight as the upper level forcing slides east. With clearing late, lows should drop into the lower 40s west of the IL River. With clouds hanging strong in SE IL, lower 50s lows will be common. An excellent stretch of fall weather will begin across the entire area on Monday. High pressure over the central Plains begins to shift east, providing light winds and dry and mild weather. Upper 60s/lower 70s highs expected. .LONG TERM...(Tuesday through Sunday) ISSUED AT 238 PM CDT Sun Oct 6 2019 The upper level pattern through mid-week features a deepening trough over the western U.S. with a closed low forming over the northern Rockies Wednesday. Downstream, upper level ridging amplifies over the Midwest, while a surface ridge axis extends from the Great Lake southwest over the local area. This to produce dry and gradually warming temperatures, reaching a few degrees above normal by Wednesday. The pattern turns more active for Thursday and Friday as the closed low rolls east, inducing lee cyclogenesis. The first classic fall cyclone of the season is forecast to track through the Plains and upper Midwest, putting us on the warm side of the storm. Warm/moist advection will increase showers and isolated storms from the west Thursday/Thursday night, while highest pops and thunder chances accompany the cold frontal passage on Friday. GFS is in better agreement with EC solution of a Friday frontal passage, though timing will be key to another day of much above normal temperatures, and thunderstorm timing. Regardless, after the front sweeps east, blustery westerly winds will advect in the coldest airmass of the season. 850mb temps are progged to dip as low as -2 to -5C Friday night and Saturday. The deep closed low is forecast to spin over the northern Great Lakes through the weekend. This would keep well below normal temperatures in place, with upper 30s lows and 50s highs common. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 635 PM CDT Sun Oct 6 2019 VFR conditions will prevail through the entire 00z TAF period. A short-wave trough evident on latest water vapor imagery over Nebraska/Kansas is creating a shield of mid-level cloudiness across central Illinois early this evening. These clouds are depicted quite well by the NAM 700-500mb layer RH field, so will be following this closely for the cloud forecast. As such, have included OVC120 at all sites initially...with clearing arriving at KPIA by 06z...then further east to KDEC/KCMI by 09z. Skies will then remain clear for the remainder of the period. Winds will be light/variable this evening, then will become NW at 5-10kt at all sites on Monday. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Barnes SYNOPSIS...25 SHORT TERM...25 LONG TERM...25 AVIATION...Barnes
Area Forecast Discussion
National Weather Service Key West FL
1047 PM EDT Sun Oct 6 2019 .DISCUSSION... A turn to wetter weather is expected over the next 24-30 hours. The wind field shown by surface obs depict an inverted trough axis off the Southeast Florida coast this evening. Loops of radar imagery and PW imagery both show a westward-moving spin as well, with an increase in PW values within the trough. Have increased PoPs late tonight over the Upper Keys to account for an increase in showers behind this vort lobe. On Monday, a broad east-west trough currently near the south coast of Cuba will lift northward across the Keys. MIMIC PW imagery currently shows a sharp increase in moisture south of the trough axis, and this air mass will arrive over the Keys as the trough passes. Recent mesoscale models and the 18z NAM spread precip across nearly the entire island chain by mid- day Monday. The 12z ECMWF holds off until Monday evening, and the 18z GFS and experimental 00z Caribbean HRRR splitting the middle with an afternoon arrival anticipated. Have conservatively nudged PoPs on Monday from 20 up to 30 percent, with room for the next shift to adjust the forecast even wetter. && .MARINE... Wind speeds are on a decreasing trend this evening. Have therefore been able to drop the Small Craft Exercise Caution headline for all marine zones except the Straits for the rest of tonight. From synopsis, a weak trough of low pressure stretches from the Bay of Campeche to the Bahamas. The portion of this trough currently over Cuba will lift slowly northward through Monday. By Tuesday, this trough axis will stall to the north of the Florida Keys. High pressure will build southward down the Sunshine State Thursday through Friday. && .AVIATION... VFR conditions will prevail at both terminals through at least Monday morning with continued dry conditions and light east winds less than 10 knots. Sometime late Monday morning, a passing shower cannot be discounted. Also during the morning, BKN clouds near FL200 to FL160 will build into the region. This will both limit sunshine and indicate showers and possible thunderstorms affecting either or both terminals during Monday afternoon. East winds near 10 knots with occasional gusts near 20 knots starting Monday afternoon. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...Haner Aviation/Nowcasts....Chesser Data Collection......DR Visit us on the web at Follow us on Facebook and Twitter at:
Area Forecast Discussion
National Weather Service Memphis TN
940 PM CDT Sun Oct 6 2019 .UPDATE... A cold front that pushed into the Mid-South this afternoon has slowed its progression southeastward and is now nearly stationary along the I-40 corridor. Showers and thunderstorms will continue to stream northeastward along the front during the overnight hours. This may lead to flash flooding in areas that have already seen a lot of rain this evening. An upper trof will swing into the area by Monday morning which will allow the front to start moving again. Cooler temperatures are not that far away as temperatures have dropped into the 50s across Missouri and even the last ob at Corning, Arkansas showed a temperature of 59 degrees. May tweak POPS and temperatures slightly. Otherwise, current forecast looks good. KRM && .DISCUSSION... /issued 250 PM CDT Sun Oct 6 2019/ Surface analysis this afternoon places a cold front from Southern Indiana back through Southeast Missouri, Central Arkansas, and into the Red River Valley of Texas and Oklahoma. KNQA WSR-88D radar trends have shown an increase in scattered showers and thunderstorms across the Mid-South in the past couple of hours. As of 2 PM CDT, mostly cloudy skies prevail across the forecast area with temperatures ranging from the 70s to around 80 degrees north of I-40 and middle 80s to around 90 degrees elsewhere. Short term models including Convective Allowing Model (CAM) solutions indicate the aforementioned cold front will move through the Mid-South tonight with better coverage of showers and thunderstorms mostly behind the front. A few strong thunderstorms to perhaps a severe thunderstorm is possible mainly through early this evening with damaging winds as the primary threat for any thunderstorms that reach severe limits. Much cooler and drier air will filter into the Mid-South on Monday with highs struggling to reach the lower 70s. A shortwave ridge will bring mainly rain free weather and moderating temperatures through mid-week. Long term models continue to indicate southwest flow aloft returning to the Lower Mississippi Valley late this week ahead of a deep upper level trough and cold front that will move into the Middle and Lower Mississippi Valleys late this week into the start of next weekend. Model run to run continuity problems continue to persist for the Thursday night through Saturday time frame resulting in a slightly slower trend than previous forecasts and lower rain chances. These rain chances will likely needed to be raised accordingly once models converge on better timing of the next cold front in subsequent forecasts. CJC && .AVIATION... 00Z TAFs Frontal-forced convective line was lifting through AR at 23Z, an hour or two earlier than the HRRR (the better performing member of the CAMs) depicted. A weak southerly jet above FL020, and the position of an upper jet core over the northern Ohio Valley will help sustain scattered TSRA well to the rear of the advancing surface front through late evening. Deepening frontal inversion and waning elevated instability should limit TS potential at all but TUP after 09Z. Low MVFR ceilings will likely be the main impact toward sunrise, followed by a slow transition to VFR from northwest to southeast on Monday. PWB && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$
Area Forecast Discussion
National Weather Service Marquette MI
745 PM EDT Sun Oct 6 2019 .SHORT TERM...(This evening through Monday) Issued at 409 PM EDT SUN OCT 6 2019 Water vapor and RAP analysis show a mid-level trof extending from northern Ontario to the central Plains. Within the trof, a couple of shortwaves are approaching Upper MI, one in northern MN and the other dropping se thru southern Manitoba. In the wake of the shortwave that passed last night and which is now over southern Hudson Bay, it`s been a breezy day across the fcst area with winds gusting to 25-35mph for the most part, but up to 35-45mph on the Keweenaw. KCMX gusted to 48mph today, and out on Lake Superior, the strongest observed wind gust was 60mph at Stannard Rock. While the morning turned sunny across the fcst area, clouds have rapidly developed this aftn due to combination of daytime heating and approaching shortwave from MN. Didn`t take long for sct shra to develop either. Gusty winds will continue for the next several hrs before subsiding toward sunset. Otherwise, as upstream shortwave over MN moves closer, expect sct shra to continue to develop. Latest SPC mesoanalysis shows SBCAPE up to around 200j/kg. So, not totally out of the question that there could be a rumble of thunder. Second shortwave currently over southern Manitoba will be over Upper MI at 12z Mon. This wave will help to maintain isold/sct -shra thru the night though pcpn should take on more of lake enhanced look with time due to the combination of cyclonic flow, weak synoptic forcing and 850mb temps falling to around 0C over sfc water temps ranging from 9-13C. The lake enhanced shra overnight will affect areas favored by w to wnw low-level winds. Expect low temps in the 40s. On Mon, with departure of shortwave, ongoing lake enhanced shra into the ne fcst area under wnw winds will end by 18z. Daytime heating will likely lead to an expansion of clouds in the morning to mostly cloudy for much of the area before 850mb thermal trof begins to shift e. Clouds will then decrease from w to e in the aftn. High temps will be in the 50s. .LONG TERM...(Monday night through Sunday) Issued at 409 PM EDT SUN OCT 6 2019 Overall, the main forecast highlights moving forward this week are: late-season warm up with temperatures running 5-10 degrees above normal for this time of year, and the arrival of a potent storm system progged to impact the region late in the week/next weekend. This storm system will bring with it the potential for moderate to heavy rain late in the week, windy conditions, and the potential for the seasons first snowflakes out west and plummeting temperatures over the weekend. Monday night return flow becomes established from west to east across the region as surface ridging center over lower Michigan slides eastward over the New England area. Expect this return flow, warm air advection regime to remain in place throughout much of the week as warm air advection increases, building the ridge over eastern Canada and a weak trough becomes further established off the coast of New England, essentially forming a weak rex block over the Northeast. This will keep the Upper Peninsula sandwiched between surface ridging well to our east, and a developing open wave/surface trough well to our west. Therefore, expect breezy southerly winds to accompany the warming trend through much of the week. Afternoon highs are expected to warm into the 60s, could see some downsloping effects further warm temperatures in some locations. Overnight lows will remain fairly mild, especially as better moisture arrives later in the week and given the breezy overnight conditions expected. Given the orientation of the surface pressure fields, magnitude of the pressure gradient and enhanced winds off the surface we will likely see wind gusts in excess of 20 mph throughout the week. Given the warm air advection and reduced insolation this time of year, it may end up being more intermittent gusts then persistent at times. Late Thursday through the weekend still looks to be the time period within the extend to keep a close eye on. While some timing is addressed below, please note that as we get closer the forecast will continue to be refined as confidence grows. A deep, potent trough will dig across the central CONUS, before lifting north across the Upper Great Lakes and eventually transitioning into a cutoff low. As the main trough digs south across the central CONUS, late Thursday we will start to see the return of better, deeper moisture and PWATs approaching the 90th percentile to near-record high for this time of year. Increasing large-scale lift, along with a strong baroclinic zone will allow the potential for moderate to heavy rain with the first wave of precipitation arriving Thursday night through Friday. With the moisture transport aimed north to south during this time period, it is possible that we could see some training precipitation and decent rainfall amounts. Opted to leave thunder out of the forecast. With the pressure gradient increasing further during this time period as well, stronger south to southeast winds will be possible. Late Friday into the weekend, longwave troughing will start to pivot across the Upper Mississippi Valley and lift north eventually becoming cutoff. This will favor cyclogenesis along the northern edge of the open wave/baroclinic zone. As quickly as the low pressure system develops and deepens, it quickly becomes occluded and slowly pivots across the Upper Great Lakes through the weekend. As the colder air wraps around the system, it is possible that we could see some wrap around snow make it into western parts of Upper Michigan. Further to the east, a potent dry slot looks to develop. When the cold air advection arrives, given the occluded nature of the system we will be under a unique southwest flow regime so don`t expect much in the way of a lake-component to the snow potential through Saturday. By Saturday night and Sunday, or rather depending on when the main cutoff low starts to gradually push eastward across Lake Superior, we will start to see more of a west-southwest to west flow regime setting up, which would favor more of a lake-component and additional chance for snow out west. The longer the cold air aloft lingers, it does look to gradually modify, so when timing becomes more clear, will need to see how moisture and thermodynamics are looking for lake-enhanced snow potential towards the latter half of the weekend. On top of the chance for the first snowflakes of the season, temperatures will certainly plummet behind the occluded front with daytime highs over the weekend expected to be 10+ degrees below normal for this time of year and it does still looks to be a fairly windy. Certainly a time period to keep a close eye on as we get closer, especially if you have any outdoor recreational plans this weekend. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Issued at 130 PM EDT SUN OCT 6 2019 VFR conditions should prevail thru this fcst period at KIWD/KCMX/KSAW. However, there is some potential for a period of MVFR cigs at KCMX late tonight and at KSAW Mon morning as an increase in low-level moisture occurs for a time following a passing disturbance. Otherwise, winds will remain gusty at KCMX tonight with gusts between 25-30 kt. An approaching disturbance will generate isold/sct -shra into tonight. Only VCSH was included in the fcst given the uncertainty on whether any of the shra will impact the terminals directly. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 409 PM EDT SUN OCT 6 2019 Ongoing marginal gales (gusts to around 35kt) across portions of western and central Lake Superior should end this evening. Westerly winds won`t diminish much though as gusts to around 30kt will continue across much of Lake Superior thru the night. Winds will diminish more notably on Mon as sfc high pres ridge approaches. With the arrival of the ridge Mon evening, winds will have fallen off to mostly under 15kt. With the departure of the high pres ridge to the e and a low pres trof moving out over the Plains for Tue/Wed, southerly winds on both days will probably gust frequently to 20- 25kt, strongest over the e half of Lake Superior. Winds should begin to increase a little on Thu as the low pres trof moves closer. Low pres will then organize on the trof and lift n as it deepens, passing over or just w of western Lake Superior on Fri. Depending on the strength and track of the low, may be looking at s, sw to w gales on Lake Superior Fri and/or Sat. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Gale Warning until 10 PM EDT this evening for LSZ243-244-263-264- 266. Gale Warning until 9 PM EDT this evening for LSZ242. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...Ritzman AVIATION...Voss MARINE...Rolfson
Area Forecast Discussion
National Weather Service Shreveport LA
1024 PM CDT Sun Oct 6 2019 .SHORT TERM.../Tonight through Monday/ We have updated the forecast with short term progs for sky, winds and dew points. The cold front is just now edging into the cwa in our NW corner with sfc gusts to 34KT at Idabel. The boundary will spread SE across the four state area bringing most of any rainfall during the overnight hours. The HRRR kind of backdoors some activity out of AR in LA with more development along I-30 after midnight. The new 00Z NAM is very similar with much light QPF and pockets of downpours. We will stay pat on our high pops tonight. No changes to pops per say aside from making an overnight grid from 03-12Z to relieve some excess after midnight wording. Get ready here comes fall overnight with 50s areawide first in the morning, while still under clouds with a wind chill. /24/ && .PREV DISCUSSION... /issued 711 PM CDT Sun Oct 6 2019/ AVIATION... For the ArkLaTex terminals, expect shifting and gusty winds overnight with a decent fropa. Shwrs/isold TS 03-06Z along I-30 and shifting down across I-20 by 09Z and KMLU/KLFK shortly after. South winds will shift to N/NW10-20KT along the boundary and then veer to N/NE 5-15KT. We will see MVFR over the cooler surface only slowly improve all morning, but lifting to VFR by Noon or so. Some nice fall weather will ensue with yet another fropa on Friday. /24/ PREV DISCUSSION... /issued 341 PM CDT Sun Oct 6 2019/ SHORT TERM.../Tonight through Monday Night/ Main feature dominating the short term is the cold front progged to move across the region overnight. Front currently located along the Red River from Wichita Falls Texas to Ardmore to Mcalester Oklahoma. Thunderstorms forecast to increase in coverage along the I-30 corridor late this afternoon. Surface heating combined with a positively tilted mid-level trough will support convection along the frontal boundary through the mid to late evening. MLCAPE values of around 2000 J/kg will provide sufficient instability to support strong thundersorms with isolated damaging wind gusts and small hail. Front to move across the region overnight with convection forecast to evolve into widespread rain and embedded thunderstorms areawide. North to northeast winds around 15 mph with higher gusts will usher in much cooler air on Monday with high temperatures forecast to only climb into the mid 70s. Post frontal low clouds to persist through much of the day before gradually clearing from the northwest during the afternoon. Overnight lows on Monday night forecast to fall into the low to mid 50s. /05/ LONG TERM...Tuesday through Sunday/ High pressure will continue to build into the region bringing in much cooler and drier air. Temperatures will struggle to reach the 80 degrees across the region on Tuesday with lows Wednesday morning in the 50s areawide. The High shifts east Wednesday allowing for southerly flow to return. Temperatures will warm into the low to mid 80s Wednesday and into the mid to upper 80s on Thursday ahead of another approaching cold front on Friday. Can`t rule out strong to severe storms with this front but there are some uncertainties with this system at this time. Our region will likely see the coldest air of the season thus far behind this front on Saturday and Sunday with highs in the lower 70s and overnight low temperatures in the mid to upper 40s. /20/ && .PRELIMINARY POINT TEMPS/POPS... SHV 65 75 55 79 / 80 30 0 0 MLU 66 77 56 80 / 70 40 0 0 DEQ 58 75 50 76 / 90 20 0 0 TXK 59 74 52 76 / 90 20 0 0 ELD 59 74 51 79 / 90 30 0 0 TYR 63 75 55 79 / 80 30 0 0 GGG 64 75 54 79 / 80 30 0 0 LFK 69 75 57 80 / 50 30 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 24/05/20