Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/04/19

Area Forecast Discussion
National Weather Service La Crosse WI
1048 PM CDT Thu Oct 3 2019 .SHORT TERM...(This evening through Friday) Issued at 217 PM CDT Thu Oct 3 2019 At 2 PM, skies were mostly cloudy across the Upper Mississippi River Valley. There were a few scattered showers being detected by surface observations and very light radar returns. Temperatures ranged from the mid-40s to lower 60s. The 03.12z models continue to show that the clouds currently over the region will dissipate late this evening. However, with the models having a bias of clearing out clouds too fast, opted to be much more pessimistic and kept skies mostly cloudy through Friday morning. This is when the ridge axis finally starts to move east of the area. Despite the clouds, low temperatures will become rather chilly (ranging from the mid-30s to lower 40s) on Friday morning. There may be some patchy to areas of frost in central and north central Wisconsin. Thought about a Frost Advisory, but with mostly cloudy skies opted not to do one at this time. The low clouds should gradually dissipate during the late morning and early afternoon. However, as this occurs, mid and high clouds will move into the area ahead of the next system. High temperatures on Friday will be mainly in the 50s. .LONG TERM...(Friday night through Thursday) Issued at 217 PM CDT Thu Oct 3 2019 The surface high and upper ridge axis will drift east of the area heading into Friday night. Meanwhile a negatively tilted surface low/upper trough will make their way into the Northern Plains. Our area will remain between these two systems Friday night, with developing return flow pulling a substantial amount of Gulf moisture northward into the Upper Mississippi Valley again. Moisture transport will increase locally late Friday night on the nose of a low level jet, nudging PWATs back into 1 to 1.4" territory across the forecast area for Saturday. As the intensifying surface low lifts into northern Minnesota, it will drag a trailing cold front through the forecast area Saturday afternoon-evening. The result will be another round of substantial widespread rainfall for the area. Rain is expected to arrive across southeast MN and northeast IA by late Friday evening, spreading into Wisconsin overnight. Bulk of the rain will progressively taper off from west to east through the day on Saturday, largely ending by Saturday evening. Still looking like very limited elevated instability, but wouldn`t rule out an embedded storm or two. Still consistent model signals pointing to the likelihood of rainfall around an inch or so across much of the forecast area, likely heaviest along and north of I-90. Looks like less rainfall down towards Grant County, which is good news given recent flooding issues there. Regardless, will need to keep an eye on this system as the area recovers from recent heavy rainfall. Deep cyclonic flow will then linger through Monday as a longwave trough drops through the eastern CONUS. This may result in spotty light showers or sprinkles at times across Taylor/Clark counties on Sunday and Monday, but ridging aloft and at the surface will quickly build into the region by Monday night into Tuesday. An expansive surface high will quickly grow to dominate most of the eastern CONUS by midweek, but its influence here will be declining as its center shifts to over the Northeast. Will have to watch for isolated light shower potential by Wednesday as weak shortwave energy arrives with an increasingly moist airmass. Models are coming into agreement with another system dragging a cold front through the region next Thursday with more widespread rain. Temperatures will remain fairly seasonable through the period with highs generally in the 50s/60s and lows in the upper 30s to 40s. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1048 PM CDT Thu Oct 3 2019 For the most part, the low clouds have remained over the region this evening. The exception is over eastern Wisconsin where a rather large hole in the clouds has developed. Satellite imagery indicates this is moving to the south for the most part but there is some slow westward expansion of the clearing. The 04.02Z RAP does show reduction in the 925mb moisture over the eastern part of the state but does not bring is west over either airport. Plan to keep both sites in the clouds until Friday morning with MVFR ceilings. The clouds should then break up once the low level ridge axis moves over the area allowing VFR conditions for much of the day. The next system will quickly advance toward the area Friday evening and spread a mid-level VFR ceiling back over both airports. Rain from this system, along with more MVFR conditions, looks to hold off until after 05.06Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...Boyne LONG TERM...Kurz AVIATION...04
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
848 PM CDT Thu Oct 3 2019 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...The 500 mb inverted trough that brought the afternoon conv to the RGV this evening will continue drifting steadily westward tonight into Fri. The afternoon and early evening conv has died down with the loss of the afternoon heating. However, the 00Z BRO sounding shows a pretty unstable and tropical airmass in place over the region with a PWAT of 2.11 inches and an MUCAPE of 3795 J/KG. The RGV airports will likely remain free of the conv over the next few hours. However, expect the conv to refire later tonight into early Friday morning as per the latest HRRR conv guidance which appears to have initialized pretty well on the recent conv. Will go with general VFR conditions over the upcoming 24 hours with some periodic reductions to MVFR conditions due to the sct passing conv. && .PREV DISCUSSION... /issued 341 PM CDT Thu Oct 3 2019/ SHORT TERM (Tonight through Friday Night): Upper low currently centered southeast of the CWA will continue to moves slowly northward tonight and Friday. This feature will contribute to the overall unsettled synoptic pattern which has persisted all week across Deep South TX and the Rio Grande Valley. An uncapped very moist airmass will once again contribute to scattered to even numerous showers and thunderstorms through Friday. Higher POPs will be indicated further east closer to the upper low, higher moisture, and better boundary layer forcing. As the upper low begins to get sheared apart on Friday night, the convective activity is expected to become less widespread. As a result, will drop off rain chances significantly, especially west of I-69C, for Friday night. Despite the increased rain chances and higher cloud cover, temps will still be overall slightly above normal. Long period 3-4 ft swells along with high astronomical October tides will produce minor coastal flooding again tonight. This will coincide several hours before and after high tide which is just after 04Z Friday. As a result, issued a coastal flood statement for the entire lower TX coast. LONG TERM (Saturday through Thursday): Once again today...the difficulty of the long term forecast lies in how models are handling the wind shift/front early next week. The ECMWF remains more bullish on the push of cooler air which leads to a stronger surface ridge punching down across the eastern Rockies into the Texas Panhandle by early 1030 mb...while the GFS is both weaker (1025 mb) and more east-west in its orientation...which allows it to quickly scoot east with more of a bridging effect for the impacts to be less of a true "front" and more of a slight reduction in heat back to or a hair above normal. Interestingly...the drier ECMWF pushes both lower dewpoints and higher daytime temperatures (given dry to super-adiabatic mixing) while the GFS has a bit more moisture as well as rain chances which keeps temperatures near average (upper 80s by day, upper 60s by morning or most). Until the situation clears up...have continued to blend forecast data but the lean here is toward the GFS simply because the upper level and strength of the surface high/source region is not sufficiently strong enough for a full-on sweeping front next week. For the sensible weather, then...the developing of flat 500 mb ridge to our west and northerly flow between it and the weakness nosing into the southwest Gulf will both shove deeper moisture into northeast Mexico and keep the surface low pinned in the Bay of Campeche. This will maintain a weak extension of the surface high from the U.S. east coast through east and southeast Texas, with light east/east northeast flow across the region under a mix of sun and clouds. Low to silent rain chances (20 to 10 percent) is the best bet...though could see a little action near South Padre early Saturday before lower coverage arrives by afternon. Temperatures will be able to recover back to the low to mid 90s in most areas with the increased sunshine/minimal coverage of showers each day. By Monday...the bridging ridge will move across the southern Plains with ridge axis extending through the Valley...and with the blended solution this picks up northeast to north winds to the breezy side near the coast but only a fresh breeze farther inland. Some deeper moisture associated with shear axis combined with enhanced low level moisture from strengthening northeast flow off the still very warm Gulf, have maintained the 30-50 percent chances coastal/Gulf but trimmed back to slight chances farther west. For Tuesday through Thursday...maintained the blended forecast which sees winds slowly veer from northeast to east/southeast and enough dry air filter in to lower dewpoints a shade, especially along and west of I-69C, and split the difference on afternoon highs which will still be 2 to 3 degrees above average for the dates (October 8-10). Morning lows will finally drop...but may remain above 70 along/east of US 77/IH 69E and could struggle below that even in rural areas of the Valley and King Ranch. Hopefully...we`ll have a better consensus on how this will play out this time Friday. Two key hazard to continue to monitor is for beachgoers. Swell period has picked up to 8 seconds today and expect this to continue through the weekend, per gradient from weakening east coast ridge and the broad low pressure from the Bay of Campeche to the northwest Caribbean. Rip currents will range from moderate to high intensity, focused at Isla Blanca park, while waves themselves will remain inviting as heights hold in the 2 to 4 foot range overall. Tidal "run up" will continue as well, and may encroach the dunes at overnight high tides after midnight Saturday and Sunday night. The good news? Tidal ranges are among the highest we see, and by midday are expected to be near the zero line above mean higher high water, which is generally the point at which foam reaches one`s toes. That said, enhanced wave `set up` with the persistent swell period should allow a bit more water than usual to run up during low tide, so all beaches will still narrow a bit even by day...but not enough to force people to set up equipment behind the dunes when the beaches are crowded. Bottom line? Expect rip current statements at some point through the weekend, with coastal flood statements and perhaps an advisory to cover the high tide rises overnight. Beyond the weekend, additional run-up is likely as the gradient and fetch pick up further, with the potential for 9-10 second swell periods and high waves offshore running onto the beach. Advisories and continued high danger rips may be common Monday through Wednesday. MARINE: Tonight through Friday night...Incoming swells due to a long fetch of moderate east- northeast flow will keep seas generally in the 4 foot range through Friday. Gradient flow will keep conditions below caution or advisory levels. Rain chances will be the highest over the waters given the uncapped and higher moisture atmospheric profile. Saturday through Tuesday Night...The big story is the wind shift/potential front and strength of the high pressure behind it. That comes Monday and continues into Tuesday. For the weekend, light winds and moderate seas (courtesy of the swell) will dominate, and rain coverage should be lower than in recent days so overall not a bad time for boating/fishing since swell will be more dominant than wind waves and seas should be 3 to 4 feet overall. By Monday, that changes, with northeast winds approaching small craft advisory conditions and seas likely responding to a combination of wind and east/northeast fetch with the tighter gradient. WaveWatch4 does not handle this situation as well, so blended with TAFB and have seas up to 6 feet in the offshore waters and 5 feet elsewhere for Monday through Tuesday morning before slowly subsiding later Tuesday into Tuesday night. Small craft exercise caution may be required for this period (Monday- Tuesday night) due to seas alone. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ This product is also available on the web at: HTTP://WEATHER.GOV/RGV Short Term/Aviation...60 Long Term/Upper Air/Graphicast...67
Area Forecast Discussion
National Weather Service State College PA
1117 PM EDT Thu Oct 3 2019 .SYNOPSIS... A frontal system will will pass through the region tonight. After a cooler day tomorrow, many areas will see their first frost on Saturday morning. After that look for a dry weekend with moderating temperatures. Wet weather will return early next week as a new frontal system moves our way. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Meso anal shows a very complex frontal system moving across the area. As of 10PM the front is just west of Wellsboro down to just about overhead State College into VA/ND east of Bedford. Radar shows just a couple of very light leftover showers over my SERN zones and given upstream trends, I generally sliced a bunch off the overnight post frontal POPs. The latest RAP and HRRR suggest this complex front will continue east this evening, clearing my SERN zones around or shortly after midnight. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/... Post frontal weather tomorrow with cooler and drier air. Any clouds will dissipate through the day, leaving most places clear by sunset. Maxes only in the u40s over the hilltops of the north, but in the m60s in the south...about 5 to 10 degrees below normals. && .LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/... The medium to long range period will be highlighted by a fairly progressive northern stream flow across the northern U.S. and a trend toward more normal to slightly below normal 500 mb heights and 850 mb temps. Leading off the period, the first significant Frost/Potential Freeze will occur across the Northern mtns of PA late Friday night through sunrise Saturday as a 1032 mb sfc high slides by just to our north. A Freeze Watch was recently posted for 3 of our northern tier counties from 06Z-13Z Sat, with min temps expected to average 32-34F, though some of the typically colder, high mountain valleys could see mins of 29-30F. As the high slides off the New England Coast Saturday afternoon and night, a rather strong llvl p-gradient will develop across the CWA with a gusty south to SE flow developing. Abundant sunshine will try to balance out the chilly temps Saturday. Mid/high level clouds will be increasing from the west pretty quickly Saturday night, within an area of increasing WAA and at the leading edge of an area of approx plus 2 sigma PWAT air ahead of a potent upper trough. Conditions will likely stay dry across most or all of the western zones through daybreak Sunday, before numerous showers spread across the NW half of PA during the day. Showers will be more scattered and favor the afternoon and nighttime hours Sunday across the Lower Susq Valley. Most model guidance indicates a backing upper flow with the region becoming located beneath a pronounced Jet Entrance Region Sunday night through Monday. This will likely greatly slow the CFROPA or temporarily stall out the boundary across PA with a moisture laden, albeit weak wave of low pressure lifting NE from the Ohio River Valley through PA. This will bring a widespread, soaking stratiform rain to start the week with GEFS 24-hour QPF expected to average between 0.50-1.00 inch. However, low GEFS probs of 2+ inches/36 hr and EC storm total QPF in the 1.5-2 inch range across the northern mtns suggests that some minor ponding/sharp rises on small streams could become a notable impact by Monday. The Tues-Thu period of next week contains a fairly high confidence for dry weather with mostly sunny days with slightly below normal temps in the 50s/60s, and fair, chilly nights in the 30s/40s. The next chc of showers will arrive sometime Friday based on a blend of the EC/GEFS and NBM. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Large area of IFR and MVFR conditions associated with low cigs and even some lower vsby across a good portion of the area. Frontal system will push through the area later tonight with improving conditions. Mainly VFR tomorrow with much better weather. .Outlook... Fri...Gusty NW winds. AM low cigs possible NW Mtns/Laurels. Sat...Patchy AM fog possible. Sun...Rain/low cigs possible, mainly N Mtns. Mon...Rain/low cigs possible, mainly W Mtns. Tue...Improving conds esp during daylight hours. && .CTP WATCHES/WARNINGS/ADVISORIES... Freeze Watch from late Friday night through Saturday morning for PAZ005-006-037. && $$ SYNOPSIS...La Corte NEAR TERM...La Corte SHORT TERM...Ross LONG TERM...Dangelo/Lambert/Evanego AVIATION...Ross/Gartner
Area Forecast Discussion
National Weather Service Goodland KS
830 PM MDT Thu Oct 3 2019 .UPDATE... Issued at 825 PM MDT Thu Oct 3 2019 GFSLamp, Rap13, HRRR model runs are in excellent agreement producing visibility reductions in fog starting around 10z and lasting through 15z or 16z for locations north of a warm front...Wray to Colby and Gove southward. Have updated the forecast to introduce areas of fog and HWO to mention threat of dense fog. With the increase in cloud cover and dewpoints from increasing southerly winds I`m a bit concerned the overnight low temperature forecast may be too cool. Will evaluate latest model data but have trended min temps up just a bit from previous forecast. Strong south winds are expected Friday with gusts to 45 mph along and west of the CO/KS border. Dust dispersion models do not show any signs of a blowing dust threat. This may be partially due to the relatively high surface relative humidity and fairly low (stable) 0-2km lapse rates. && .SHORT TERM...(This evening through Friday) Issued at 200 PM MDT Thu Oct 3 2019 Old front has stalled against the Front Range, but will gradually return eastward as a warm front tonight and Friday as a large upper trough moves across the northern Rockies. Clouds will gradually increase from the south tonight, as do surface winds, which will keep low temperature in the middle 40s. Precipitation chances will begin to creep back into the far southeastern counties overnight. Precipitation will be very light, but there is some low MUCAPE forecast so decided to add a mention of thunder. Friday will start out mostly cloudy over the entire area, then some partial clearing in western areas on the warm side of the front. Eastern areas will be cloudy all day and cooler. So, there will be a rather large east to west temperature gradient, with highs ranging from the upper 50s east to upper 70s west. Precipitation chances will continue, mainly in the east in the morning, then another batch of showers/thunderstorms in the afternoon as the main upper trough ejects into the central and northern High Plains. Best forcing will remain north, so expecting only scattered coverage. Weak instability is forecast in the afternoon in northeast Colorado and along the Kansas border area by the more aggressive CAMs (1000-1500 j/kg), and fairly decent deep layer shear of around 40 kts, so cannot totally rule out an isolated severe threat for marginally severe hail/wind, but with the combination of weak instability/weak forcing the probability is rather low. It will be windy, with south winds 20-30 kts and higher gusts by the afternoon. Precipitation chances will move out to the east through Friday night with gradual clearing. Low temperatures will be in the 40s and 50s. .LONG TERM...(Friday night through Thursday) Issued at 228 PM MDT Thu Oct 3 2019 Forecast concerns will be colder low temperatures into Monday morning, and winds/fire weather on Saturday. Satellite showing an amplified but still progressive flow from the Pacific into eastern North America. Upper trough over the western portion of the country with ridging over the east. Saturday/Saturday night...Dry conditions expected. Strong upper jet moves across the area in the morning into early afternoon. The day will begin with a strong cold front just having just cleared the area. Pressure gradient and 3 hour pressure rises would indicate windy conditions. There looks to be some decent downward motion in the afternoon. The Gfs is mixing down stronger winds, and get close to warning criteria. However most of output fits with the previous forecast of near 45 mph gusts. This and collaboration with neighbors led to using Consmos for winds. It looks like the winds start decreasing early in the afternoon as the surface ridge starts moving into the region. Forecast blend maxes look reasonable. For the affects of this on Fire Weather, refer to that section below. The winds become light during the night, especially in the eastern portion of the area. Right rear quadrant of the upper jet moves across during the night. Models are indicating some mid to high level cloud cover which could slow the cooling. Mos output/some consensus output support going lower than the forecast blend. Model certainty output led me to lower the blend a few degrees but potential there for more cooling. At the very least some frost is expected. Sunday/Sunday night...Dry conditions expected. Right rear quadrant of the jet moves across during the morning. At the beginning of the day it looks like a reinforcing shot of cold air arrives which causes breezy to windy conditions. Again forecast blend maxes look reasonable. Winds drop off again during the night. However they do not look as light as models shift the winds around faster. After looking at model certainty output, I lowered the lows again more frost occurring. Monday through Thursday...Deterministic output starts out in good agreement and then become increasingly different by the end of the period. This primarily has to do with how the models handle the northern system in both speed and amplitude. Fast west to northwesterly flow aloft and dry conditions looks to be prevail into Wednesday. Then in some form or other the above mentioned trough move across. General consensus is the bulk of the lift and chance of precipitation look to be to the north of the area. So the slight chance pops the forecast blend gives me looks reasonable. Also precipitation looks to be ongoing when temperatures get cold enough for some light snow in northern Yuma County Wednesday night. Little if any accumulation expected. Due increasing model disagreement, am leaving temperatures alone. If current forecast blend is close, widespread temperatures in the 30s look to occur Wednesday and Thursday nights. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 450 PM MDT Thu Oct 3 2019 Sub vfr cigs move north reaching KGLD around 06z and KMCK near 12z with winds from the southeast at 7 to 15kts (highest at KGLD). Could see some mist as well at KGLD toward 12z. Cigs improve to vfr at KGLD around 20z or so while remaining sub vfr at KMCK as the axis of low level moisture lifts northeast. South winds increase at KGLD with gusts over 35kts expected. At KMCK southeast winds gusting over 30kts expected during the afternoon hours. && .FIRE WEATHER... Issued at 228 PM MDT Thu Oct 3 2019 Dewpoints look to remain low into the afternoon. However the winds look to be lower in the afternoon than in the morning. Relative humidities are 15 to 20 percent in eastern Colorado. However that is when the winds are the lightest there. So it appears that conditions will not be near critical. If the timing of the front would slow down then there would be a better combination of stronger winds and low relative humidities. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...99 SHORT TERM...024 LONG TERM...BULLER AVIATION...99 FIRE WEATHER...BULLER
Area Forecast Discussion
National Weather Service Marquette MI
750 PM EDT Thu Oct 3 2019 .SHORT TERM...(This evening through Friday) Issued at 317 PM EDT THU OCT 3 2019 Mid-upper level trough axis over the Upper Great Lakes as noted on water vapor imagery and RAP analysis will shift east later this evening. Forcing associated with the trough should also shift east by this evening as any remaining rain showers will likely be attributed to pure lake effect convection as temps at top of 4-5 kft convective layer will be -3 to -4c resulting in a lake delta-t of around 17C. Convergent low-level northerly flow will help focus lake effect rain bands into the higher terrain of west and north central Upper Mi this evening. Late tonight into Friday, increased ridging and associated lowering of the subsidence inversion to 2-3 kft from the west overnight into Friday should help bring to an end to isolated lake effect rain showers over the western higher terrain late tonight and over the north central higher terrain by early Friday. Otherwise, mid level and sfc ridging building into the area should bring partial clearing and slightly warmer conditions to the area. Diurnal cu could still linger, especially over the higher terrain of north central Upper Mi favored by upslope ne flow, as 850 mb temps fcst to be 2-3C. Look for min temps tonight ranging from the mid 30s interior west to the lower 40s near the Great Lakes. Expect highs Friday generally in the lower to mid 50s. .LONG TERM...(Friday night through Thursday) Issued at 448 PM EDT THU OCT 3 2019 Over the next 7 to 10 days, a typical progressive fall pattern will prevail, featuring two trofs that will swing across the northern CONUS. The first will reach the western Great Lakes late this weekend and the second Thu/Fri next week. As would be expected under a progressive regime, temps will fluctuate btwn above and blo normal. Right now, it does not appear that daily temp departures from normal will be significant. As for pcpn, the first trof will feature a vigorous shortwave lifting across the northern Great Lakes Sat night, likely providing a period of shra Sat/Sat evening. This wave will also be a wind maker, gales for Lake Superior and likely wind advy for the Keweenaw. Trailing shortwave moving thru the trof will keep sct shra around into Mon. Dry weather should then prevail Tue/Wed. Next approaching trof will bring shra back into the fcst for Thu/Fri. Beginning Fri night, with mid-level ridge over the Upper Great Lakes and associated sfc high pres over eastern Lake Superior early, the evening will start quiet. In advance of the shortwave trof approaching the western Plains, developing waa/isentropic ascent across the northern Plains will lead to high clouds spreading downstream and across the fcst area during the night. However, it looks like the increase in high clouds will be slow enough to allow for a potential widespread frost across the interior central and east. That said, there is one complication, and that would be the possibility of lake clouds developing/spreading off Lake MI under developing light se winds. Late in the night, leading edge of 850- 700mb moisture transport and isentropic ascent may reach the far w toward 12z. So, -shra may arrive there near sunrise. As upstream shortwave moves to the Upper Mississippi Valley by Sat evening, 45-50kt low-level jet translates to the Upper Lakes along with a good push of 850-700mb moisture transport and deep layer forcing per q-vectors. Thus, expect shra to spread across the fcst area from w to e during the day on Sat. Not out of the question that there could be a rumble or two of thunder, but instability is really lacking for tsra. Shra will end Sat evening as cold front passes and mid-level dry slot arrives. With cyclonic flow and the edge of deeper moisture brushing the nw fcst area, there could be a few -shra thru the night across nw Upper MI. Otherwise, main concern will shift to wind for Lake Superior and the Keweenaw. Favorable aspects for stronger winds are shortwave briefly taking on a negative tilt as it swings across the area, favorable isallobaric wind component (though pres rise/fall couplet is not especially notable at roughly +4 and -5mb/3hr), and upwards of 45kt in the mixed layer. Negatives are lack of strong caa as 850mb temps only fall around 4C, and for the Keweenaw, low-level winds are more of a wsw direction rather than the more favorable wnw direction. At least for now, looks like a set up for a wind advy (sustained winds of 30mph or more and/or frequent gusts 45mph or greater) for the Keweenaw Peninsula overnight Sat night thru at least Sun morning. It is noted that the last couple of GFS runs have showed 4-5hrs with potential to mix to 55kt winds over the Keweenaw. Will be something to monitor for a potentially higher impact wind event. With gales on Lake Superior, large waves may lead to some lakeshore flooding/erosion issues around the w side of the Keweenaw on Sun. Elsewhere across the fcst area, expect breezy conditions on Sun with gusts to 30-35mph or so. Cyclonic flow/cold air aloft may support isold -shra on Sun. Trailing shortwave passing late Sun night/Mon morning will then maintain isold/sct -shra thru Sun night into mainly Mon morning. Dry weather will follow Tue/Wed as mid-level ridging passes. Expect warming as well as sw low-level flow takes hold. Wed should be the warmest day of this fcst period with high temps potentially well into the 60s. Next trof will shift across the western Great Lakes late Thu/Fri, bringing a period of shra. && .AVIATION...(For the 00Z TAFS through 24Z Friday afternoon) Issued at 750 PM EDT THU OCT 3 2019 Northernly flow from Lake Superior will persit through the evening, bringing IFR conditions to all sites. KIWD and KSAW will occasionally see LIFR conditions before the cloud base lifts. By mid morning, all sites should be MVFR with continued lifting after that thanks to an incoming ridge. Northern flow will also bring scattered lake effect rain showers to all sites as well. As the ridge settles in, expect winds to be light to VRB at all sites. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 317 PM EDT THU OCT 3 2019 Northerly winds of 15 to 25 knots this evening will relax blo 20 knots late tonight into Friday. Light and variable winds are still expected by Friday afternoon as fairly strong high pressure moves overhead. Southerly winds increase ahead of the next low pressure system, with a good bet for southerly gales to 35 knots over the east half of the lake ahead of the system late Saturday with widepread sw-w gales to 40 knots behind the system for late Sat night into Sunday. West winds diminish blo gales Sun night and by sunrise Monday should diminish to 20 knots or less and remain that way into Tue. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...Voss LONG TERM...Rolfson AVIATION...JP MARINE...Voss
Area Forecast Discussion
National Weather Service Shreveport LA
811 PM CDT Thu Oct 3 2019 .UPDATE... True cold front late this evening was located across S OK into N AR but a prefrontal trough has made good progress into our region and this combined with ample lift from an upper level disturbance across SE TX and abundant instability from daytime heating resulted in scattered to numerous thunderstorms earlier today and we are still dealing with the aftermath this convection at this late hour. A large outflow boundary exists from SW AR into NE TX with convection continuing to develop/propagate to the west and northwest in its wake. Coverage is significant enough such that will increase pops for the remainder of the evening hours across portions of NE TX/SW AR and NW LA. Latest HRRR has come in suggesting that we may not see more than isolated coverage at best late tonight through the predawn hours on Friday so lowered pops to slight chance variety after midnight. Overnight low temperatures are in good shape with upper 60s to lower 70s areawide as the true cold front to our north should slowly backdoor itself to near the I-20 corridor of NE LA by 12z Fri. Update out shortly...13. && .PREV DISCUSSION... /issued 537 PM CDT Thu Oct 3 2019/ AVIATION... Scattered to numerous showers and thunderstorms continue near or in the vicinity of most of our terminal locations late this afternoon. Will therefore prevail VCTS at all terminals through much of the evening. E TX terminals will prevail VCTS through 04z as latest HRRR shows convection through the remainder of the night remaining mostly east of our NE TX terminal locations. Therefore for the TXK/ELD/SHV and MLU terminals, these high res solutions suggest that convective coverage is significant enough to keep VCTS going through much of the night. At these terminal locations, mentioned VCTS through 04/08z with coverage likely beginning to diminish after that hour. 13 && .PRELIMINARY POINT TEMPS/POPS... SHV 72 90 68 91 / 60 30 0 0 MLU 72 90 67 93 / 30 20 10 0 DEQ 69 83 63 88 / 30 20 0 0 TXK 70 85 63 89 / 50 20 0 0 ELD 68 85 63 91 / 60 20 0 0 TYR 72 89 68 91 / 60 30 10 0 GGG 71 89 67 89 / 60 30 0 0 LFK 71 91 69 89 / 30 20 20 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 13/13
Area Forecast Discussion
National Weather Service Tulsa OK
948 PM CDT Thu Oct 3 2019 .DISCUSSION... Cold front has cleared the forecast area this evening, and will remove the evening pops in southeast Oklahoma and west central Arkansas. Cloudiness across the far northwest part of the forecast area is likely to expand some to the southeast overnight, and the latest HRRR does show a few showers developing prior to sunrise. Thus will leave the low pops as is for late tonight in parts of northeast Oklahoma. Have also made just a couple minor adjustments to low temperatures tonight. Update on the way. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ SHORT TERM...20 LONG TERM....05 PLATE
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
535 PM MDT Thu Oct 3 2019 .DISCUSSION...(This Evening Through Thursday) Issued at 218 PM MDT Thu Oct 3 2019 Upper-level ridging was over the CWA per water vapor images and the RAP model analysis. Surface high pressure over the eastern Dakotas and a trough over central MT/WY has resulted in a tightening pressure gradient across the CWA, with correspondingly gusty south winds. As an upper-level trough over the West Coast approaches the CWA tonight and Friday, a strong low-level jet stream (up to 50 kt) will develop over the CWA. This will allow for continued gusty south winds over northeastern WY and western SD tonight, and over the SD plains on Friday (where marginal wind advisory conditions may be met). Conditions are not ideal for extreme downslope winds over the northern foothills tonight, but it is something that bears watching. A narrow sliver of MLCAPE from 500-1000 J/kg will develop over northeastern WY Friday afternoon, which when combined with the strong Q-G forcing, a dry boundary layer, and strong deep layer shear, should be conducive to a few high wind-producing thunderstorms. The upper trough will swing through the CWA Friday night, bringing scattered showers and thunderstorms, along with some snow to the Black Hills and northeastern WY (amounts 1 inch or less). Strong northwest winds will develop late Friday night and Saturday behind the cold front as 850-mb winds reach 50 kt along with modest cold advection. Sunday will be less windy but still cool as northwest flow aloft continues. Model ensembles support upper ridging Monday and Tuesday, leading to above-average temperatures and dry weather. The next cold front is slated to move through the CWA Tuesday night, with reasonably good agreement among the ensembles on the timing. && .AVIATION...(For the 00Z TAFS Through 00Z Friday Evening) Issued At 532 PM MDT Thu Oct 3 2019 VFR conditions are expected through Friday afternoon. A developing low level jet will low level wind shear to much of the area tonight. Gusty south winds are expected on Friday. A cold front will move into northeast Wyoming late Friday afternoon with a chance of showers and thunderstorms. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...None. && $$ DISCUSSION...Bunkers AVIATION...7