Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/29/19

Area Forecast Discussion
National Weather Service Gaylord MI
1039 PM EST Sat Dec 28 2019 .UPDATE... Issued at 939 PM EST Sat Dec 28 2019 Initial area of warm air advection driven light precipitation rotating slowly north across the Tip of the Mitt and southern eastern upper Michigan this evening. This precipitation is falling as a mixture of light rain/snow. Low level environment is much drier further south, keeping much of the area south of M-68 dry. That will eventually change as we head through later tonight into Sunday morning as corridor of extremely impressive moisture rotates northeast into the region. Low level thermal profiles keep this primarily rain across northern lower, with a freezing rain/snow mixture across eastern upper. Still looking like some light ice accumulation by morning, with heavier ice amounts during the morning hours of Sunday. && .NEAR TERM...(Through Tonight) Issued at 320 PM EST Sat Dec 28 2019 ...Freezing rain potential in Eastern Upper late tonight... High Impact Weather Potential...Freezing rain potential in Eastern Upper Pattern Synopsis and Forecast: Ridging persists along the west coast with deep troughing along the Rockies. This troughing forms into a cut-off low and swings up through Nebraska toward the upper Great Lakes overnight. Shortwave ridging which gave us some decent clearing this morning is continuing to push east this afternoon. Mid level moisture is slowly undercutting it from the southwest. Mid and upper level clouds have increased through the day, but profiles are likely still very dry in the low levels over nrn Michigan...radar returns crossing mid Michigan through the day haven`t been reaching the ground...with little more than haze and mist reported in surface obs. The 1003mb surface low is currently in Kansas, with its warm front extending through KS/MO into the Ohio Valley. Warm air advection is well underway across much of the midwest with widespread fog, rain and freezing rain. A broad area of precipitation, aided by impressive dynamics ahead of the wave, will continue to move northeast toward the Upper Great Lakes through the evening. Radar coverage is trying to slowly fill in over southern Wisconsin. But surface obs in this area are reporting drizzle and ice needles. Heading into the evening and overnight rain chances slowly increases as moisture and great forcing ahead of the wave overspread the area. Saw no reason to deviate much from inherited pops overnight given uncertainty in low level saturation timing. Guidance tries to push above- freezing air over ern upper below the 900mb level before midnight, but wet bulb cooling should take over once precipitation starts. The low level jet doesn`t look to get into the region until closer to 4 or 5 am. This may impact how quickly and how much warm air remains in the area after saturation. To further add to the forecast icing uncertainty: both the RAP and the NAM struggles to keep the low saturated, possibly due to cold/dry easterly flow out of Ontario. Overall think icing amount through daybreak is somewhat diminished, but still a threat. && .SHORT TERM...(Sunday through Tuesday) Issued at 320 PM EST Sat Dec 28 2019 ...Above normal temps with widespread precip and windy conditions... High Impact Weather Potential...Widespread rain for all of Northern Michigan...with freezing rain into Sunday morning across Eastern Upper Michigan. Heavy rain is possible...especially late Sunday night into Monday. Windy conditions will likely lead to lakeshore flooding. Turning colder Monday night into Tuesday with some accumulating snow possible. Pattern Synopsis/Forecast...Deepening low center will reach Southern Minnesota by 12Z Sunday and then hold over that general area thru Sunday night. A second low will develop along the associated cold front and lift northward...eventually merging with the Minnesota low right over Northern Lake Michigan by Monday morning. This low will actually retrograde back thru Lake Superior Monday afternoon... Monday night and Tuesday. Several waves of precip will impact our region Sunday thru Tuesday. Widespread rain showers will continue to fall across our entire CWA on Sunday...some of which will fall as freezing rain across Eastern Upper Michigan Sunday morning. Winter Wx Advisory extends into Sunday afternoon...but appears that most of the freezing rain potential will be during the morning before surface temps begin to warm to and just above freezing toward midday and into early afternoon. Will certainly keep the Winter Wx Advisory for Eastern Upper Michigan in tact with the expectation of up to a tenth of an inch of additional ice accumulation possible during Sunday morning. Precip should switch over to all rain across Eastern Upper Michigan for several hours Sunday afternoon before additional chances of freezing rain rears its ugly head again Sunday night as surface temps drop to around the freezing mark with sunset. Will certainly need to keep an eye on this potential return of freezing rain during busy holiday travel. Precip type across Northern Lower Michigan will remain all liquid all day Sunday and thru Sunday night as strong WAA persists ahead of the stalled low. There is also a slight chance of thunder across Northern Lower Michigan on Sunday thanks to a narrow axis of weak instability and enhanced 850 mb theta E along and ahead of the associated warm front as it lifts thru our region. The potential for heavy rain will be greatest late Sunday night into Monday morning as the previously mentioned secondary low lifts northward toward Michigan...merges with the upstream low and further deepens right over our CWA by 12Z Monday. Deep moisture and strong low level convergence will produce widespread rainfall with periods of embedded heavy rainfall possible. Have issued an ESF to discuss this potential...and will need to further evaluate the heavy rain/ flooding potential as this event draw closer. Also...lakeshore flooding may become an issue Sunday into Monday as gale force winds develop on the Lakes. Temps will remain above normal thru Sunday...with high temps ranging from the mid 30s across Eastern Upper Michigan to the mid to upper 40s across our SW and southern counties. Overnight lows will cool mainly into the 30s. Things begin to change on Monday as CAA kicks in from west to east across our CWA...dropping our temps and gradually mixing some snow in with the ongoing rain. Precip type should change over to all snow Monday night into Tuesday as CAA begins to get the lakes involved...with some accumulation expected especially across NW Lower Michigan. Low temps Monday night will fall mainly in to the mid to upper 20s. High temps on Tuesday will only warm a few degrees into the low to mid 30s. .LONG TERM...(Tuesday night through Saturday) Issued at 320 PM EST Sat Dec 28 2019 High Impact Weather Potential...Minimal. Generally small chances of rain and snow into the weekend. Pattern Synopsis/Forecast...Some light W/NW flow lake effect snow showers will continue into Tuesday night. Surface ridge axis will build into Michigan on Wednesday and slide east of our state by Wednesday night. Two surface lows will approach the Great Lakes Wednesday night thru Thursday night. One northern stream low will slide eastward thru Canada and the other will lift NE thru the Ohio Valley to the Mid Atlantic seaboard. Neither system will take direct aim at our state...with Michigan positioned between any significant lift or moisture from each. However...cannot rule out small chances of precip across our CWA. Temps will rebound a bit during the end of the week with high temps warming above freezing for most of our area Thursday...Friday and Saturday. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 600 PM EST Sat Dec 28 2019 Deep low pressure will lift out of the Southern Plains and into the Upper Mississippi Valley thru Sunday night. Deep moisture and warm air will continue to surge northward ahead of this system and into the Western Great Lakes region...producing widespread showers across all of Northern Lower Michigan tonight into Sunday night. There is also a slight chance of thunderstorms on Sunday...but the chance is too small to include in the TAF for now. Conditions will gradually deteriorate to MVFR and eventually IFR as this widespread precip develops. LLWS will impact all of our TAF sites late tonight thru Sunday morning. E/SE surface winds AOB 10 kts this evening will strengthen overnight and Sunday...with gusts to 20 to 30 kts expected on Sunday. && .MARINE... Issued at 320 PM EST Sat Dec 28 2019 Winds will turn out of the southeast this evening as a strong low pressure system approaches the area. Strength increases overnight in response to the strengthening pressure gradient. Strong winds with frequent gusts into gale force territory will be likely through the day Sunday and into Monday morning. This incoming storm system will also produce widespread moderate rainfall across the entire area. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY until 4 PM EST Sunday for MIZ086>088-095- 096. LH...GALE WATCH from 6 AM EST Sunday through Monday morning for LHZ345>348. SMALL CRAFT ADVISORY until 4 PM EST Sunday for LHZ349. LM...GALE WATCH from 6 AM EST Sunday through Monday morning for LMZ341-342. SMALL CRAFT ADVISORY until 4 PM EST Sunday for LMZ323-344>346. LS...GALE WATCH from 6 AM EST Sunday through Monday morning for LSZ321-322. && $$ UPDATE...MB NEAR TERM...STJ SHORT TERM...MR LONG TERM...MR AVIATION...MR MARINE...STJ
Area Forecast Discussion
National Weather Service Quad Cities IA IL
744 PM CST Sat Dec 28 2019 .UPDATE... Issued at 737 PM CST Sat Dec 28 2019 The forecast is pretty well in hand for such a wild event. Rains are rapidly lifting north, but have been slow to push east (which makes sense in a negatively tilted upper low). That slow progression has ended the fog quickly west where continuous light to moderate rain is taking place, and in the northeast 1/3, to improvement has occurred yet in dry/drizzle through 730 PM. However, THAT`S GOING TO CHANGE BY 8 PM. Radar shows an eastward extent to the WAA rains coming up from the south, and that should effectively end our dense fog event. Rains thus far have followed our QPF forecast, of highest totals in the far west. The HRRR continues to show that this will hold trough 9 PM, then shift east with the heavier/hr rates. Other than walking out the Fog advisory counties, and tweaking the qpf and pops, the forecast appears in good shape tonight and no major updates expected. && .SYNOPSIS... Issued at 327 PM CST Sat Dec 28 2019 The latest sfc analysis was indicating a quasi-stationary frontal boundary acrs central KS and MO, with main low rolling northeast out of the OK panhandle ATTM. Brisk southeast sfc winds and moisture advection fueling areas of fog/some dense to the north of the boundary, with fog headlines having to be issued and expanded earlier today. Stout 40-50+ KT southerly LLVL flow to lee of large Rockies upper trof complex conveyor-ing ample moisture up off the western gulf, indicated by precipital water feed of 1+ inches up toward the region. 12 hour highs will occur right before 6 PM, with the Hwy 20 corridor barely getting around 40 by then while the far south makes it into at least the lower 50s. && .SHORT TERM...(This Evening through Sunday) ISSUED AT 327 PM CST Sat Dec 28 2019 Tonight...A wet, increasingly mild night looks to be in store as a large area of showers and even some embedded thunder make their way up acrs the area tonight in the above described unseasonable warm moist conveyor. Areas of fog, drizzle, lighter rain to be replaced by this incoming activity, although any let up in the rain will foster more fog development even with southeasterly sfc winds of 10- 20 KTs overnight. Will let ongoing fog headlines ride with redevelopment, darkness settling in, and fog variability in mind, and there still may be a need to expand northward if the dense banks grow before the widespread rains make it up to the northern CWA. As for more rain, the PWAT`s of an inch or more, conveyor orientation to the incoming showers with some thunder, and forcing to lee of large upper trof all suggest another round of unseasonable rainfall of up to an inch to occur by 12z Sunday morning. Fortunately the heavier rain axis appears to be setting up to stream acrs mainly along and west of the MS RVR, avoiding an overlap from this morning`s heavier rains of 0.40 to over three quarters of an inch along and east of the MS RVR. But still expect some ponding of water and rising creeks in areas that get the heavy rain axis tonight west of the MS RVR, and there will be some passing bands of moderate to locally heavy bouts of rain to the east also possibly producing some urban and small stream nuisance flooding overnight into early Sunday morning in areas that already have received over half an inch of rain earlier today. In-sweeping dry slot with breezy south to southwest winds to scour out the rains to the north and east after 3 to 4 AM or so. This feature also to erode any lingering fog from south-to-north by Sunday morning. A stronger embedded thunderstorm tonight may be able to produce some pea size hail, as well as enhanced localized rainfall swaths, but better instability for severe storms remains to the south acrs the southeastern plains into central MO. Will bank on marginal lapse rates and strong layering/inversion aloft to prevent a wet mix down of brisk 50+ KT southwest winds aloft. Non-diurnal temp trends continue tonight as warm front pulls up through the CWA by 06z to 08z or so. Temps to warm into the low to mid 50s almost CWA-wide, with a few mid to upper 50s possible in the south and east. Some worry that with the conveyor of showers the models are a bit quick with northward retreat of the warm front, but still expect a warm surge toward Sunday morning even with a slowed progression. Sunday...A breezy unseasonably mild dry slot day, until continued LLVL moisture feed interacts with convergent trof spiraling in from the southwest off occluding cyclone rolling into southwestern MN possibly produces some banded/linear light showers or rain in spots later in the afternoon. Expect breezy southwest sfc winds of 15 to 25 MPH at times until they decrease by late afternoon. With temps well up in the 50s at the the start of the period, mixing dry slot air/winds could zoom morning highs in the upper 50s to around 60 along and east of the river, before the warm sector wedge gets shunted off to the east. Will add a climate section as a few climate sites not all that far off of record highs for the 29th, and Dubuque having the best chance of making it. .LONG TERM...(Sunday Night through Saturday) ISSUED AT 327 PM CST Sat Dec 28 2019 Key Messages: 1. Another round of rain/showers looks to brush the eastern CWA Sunday evening. 2. Increasing potential for light snow early in the week attendant to a slow moving closed low. 3. Temperatures look to moderate modestly above normal mid to late week, with low confidence system and precipitation chances late week. Sunday night: Another burgeoning shield of precipitation is expected to brush our eastern CWA Sunday night, as a vort max rotating through the base of a deep upper trough lifts into the Great Lakes with additional ascent provided from divergence in left exit region of cyclonically curved upper jet. Thermal parameters support all rain on the precipitation type. The rain should diminish early overnight as the lift departs. Attention then turns to slow moving upper low to our west. As it approaches expect to see the dry slot fill in with very light precipitation overnight Sunday night, especially across our western counties. Cooling temperatures aloft will result in precipitation mixing or changing to snow, with only minor accumulation possible and mostly on grassy or elevated surfaces. Monday and Monday night: Will keep trends from overnight Sunday going for much of Monday, with a continued filling of dry slot with very light precipitation on Monday with approaching closed low. Continued cold advection on gusty westerly winds will result in a mix of rain/snow going to snow. Temperatures likely won`t rebound much on Monday but more than a few degrees, with readings mostly in the lower to middle 30s by afternoon. Little, if any, accumulation is expected on Monday and would be mostly confined to grassy or elevated surfaces should it occur. Monday night there is growing signal for accumulating light snow, as model consensus grows toward a stronger vort max rotating down the backside of the Great Lakes closed low into the region accompanied by a reinforcing cold front. ECMWF is most aggressive with strength and subsequently a bit wetter than other models advertising 0.1 to 0.2 inch, and so will need to monitor as in general a little uptick noted in qpf albeit still light. But if stronger trends persist then we could see potential for an inch or two of accumulation Monday night especially from around Quad Cities north/east. And brisk winds leading to colder air with lows in the 20s Monday night and chills mostly in the teens by daybreak. Tuesday and Tuesday night: Any lingering light snow should end by early in the day. In the wake, a chilly and brisk New Years Eve day with highs mostly around 30 or in the lower 30s. Good news is that it looks tranquil to end 2019 and for any travel or festivities, as high pressure builds in. It will be cold with lows overnight in the upper teens to mid 20s. Wednesday through Saturday: First few days of 2020 look to see moderating temperatures modestly above normal by some 10-15 degrees with widespread highs in the 40s, as split flow pattern develops. Considerable uncertainty exists in this pattern with phasing potential of both northern and southern streams. Consensus with 12z model suite is phasing generally occurring to our south/east late week, albeit though with some westward shift in some of the medium range guidance, thus the late week period does bear watching and for now contains the only precipitation chances in this period. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) ISSUED AT 532 PM CST Sat Dec 28 2019 Very poor flying weather will continue tonight and Sunday, as a wet winter storm system moves through the area. Widespread rain, dense fog, low cigs, and low level wind shear winds will bring dangerous challenges to anyone flying overnight. By morning, some improvement to MVFR is possible as a dry slot of air wraps into the low pressure system. Winds will shift from east tonight to south Sunday. No freezing rain is expected in eastern Iowa or Illinois. && .HYDROLOGY... Issued at 1125 AM CST Sat Dec 28 2019 Unseasonably heavy rain event for December underway, with first slug of rain having deposited amounts of 0.3 to 0.8 inch over portions of east central and southeast Iowa, northeast Missouri and northwest Illinois. As a result, seeing some response in tributary rivers with rises beginning on portions of the lower Rock, lower Wapsipinicon, Skunk, La Moine, and lower Iowa basins. Another wave of moderate to heavy rain organizing in the Plains will lift up across the area tonight, and likely deposit another 0.5 to 1 inch across the Hydrologic Service Area. The break, or period of mainly lighter rain/drizzle, in-between these two slugs of heavier rain combined with an unfrozen soil should allow for some infiltration. Thus, while this second round of rain will likely bring additional rises on area tributary rivers they should be predominantly within bank, but could come close to flood stage at a few locations. The sites to watch for potentially nearing flood stage currently are the Iowa River at Marengo, Pecatonica River at Freeport, and English River at Kalona. This is largely due to anticipation of additional heaviest rains falling in portions of these basins with forecasts having input additional rainfall over 1 to nearly 1.5 inches over the next 48 hours beginning 12z today. In addition, the input from some of the tributary rivers will likely lead to rises on the lower portions of the Mississippi River next week, with Burlington and Gladstone possibly coming close to flood stage. These rises on the tributaries and the lower Mississippi River will be based on just how much additional rain occurs, and where the axis of heaviest occurs over the next 48 hours. Confidence on extent or magnitude of rises on area rivers is low given unfrozen soils allowing for some infiltration, but will be monitored closely given unseasonably high basin average rainfall around 1 to 1.5 inches being forecast for this time of year. && .CLIMATE... ISSUED AT 327 PM CST Sat Dec 28 2019 Record Highs for December 29... Moline.........65 in 1984 Cedar Rapids...60 in 1984 Dubuque........52 in 1984 Burlington.....65 in 1984 && .DVN WATCHES/WARNINGS/ADVISORIES... IA...Dense Fog Advisory until midnight CST tonight for Clinton- Dubuque-Jackson-Scott. IL...Dense Fog Advisory until midnight CST tonight for Bureau-Carroll- Henry IL-Jo Daviess-Mercer-Putnam-Rock Island-Stephenson- Whiteside. MO...NONE. && $$ UPDATE...Ervin SYNOPSIS...12 SHORT TERM...12 LONG TERM...McClure AVIATION...Ervin HYDROLOGY...McClure CLIMATE...12
Area Forecast Discussion
National Weather Service North Platte NE
538 PM CST Sat Dec 28 2019 .SHORT TERM...(This evening through Sunday night) Issued at 313 PM CST Sat Dec 28 2019 There are a few main concerns in the short term period. First concern is with the pops for the rest of today/evening and into Sunday. Adjusted the pops lower, especially through this afternoon across southwest Nebraska and increased pops across northern and north central Nebraska. The increase in pops is due to convective type showers that have continued to develop all day across north central and northern Nebraska. Decided to trend towards consshort model as this seemed to have a better handle on the convective showers across north central Nebraska. Across southwest Nebraska drier air has inhibited much precipitation this morning and early afternoon and the trend looks to continue the rest of the afternoon and early evening, however snowfall is expected to fill in across southwest Nebraska later this evening but some uncertainty remains in just how much snowfall will occur across southwest Nebraska. Forecaster confidence is moderate in snowfall amounts across north central and northern Nebraska where confidence is greater in the amount of available moisture along with changeover timing to snow. Confidence is lower across southwest Nebraska as there a several uncertainties that could attribute to snowfall amounts but decided to trend toward lower amounts based on the lack of moisture seen this morning and early afternoon along with temperatures remaining warmer all morning until presently. The next concern in the short term period is the intensity of the surface winds. Looking at bufkit soundings from the NAM, RAP, HRRR and SREF there are strong winds in the sfc to 800 mb layer with the most recent HRRR having the highest wind speeds at 60+kts between 900 and 800 mb layer for Sunday night. After collaboration with surrounding offices agreement was made to increase wind speeds for tonight through Sunday, with the increase of wind gusts up to 45 mph and approaching 50 mph in some locations. Also to note, wind chills will hover near to slightly below zero for Sunday night into Monday. .LONG TERM...(Monday through Saturday) Issued at 313 PM CST Sat Dec 28 2019 The main concern in the long term will be Monday winds. Confidence in increasing in higher wind speeds for Monday morning into the afternoon. An increase in wind speeds on Monday with wind gust of 40 to 45 mph possible. There is concern that with the increase in winds on Monday that blowing snow could remain in issue, especially for north central and portions of central Nebraska, additional headlines may be needed for Monday and will continue to monitor. Wind chills on Monday night will dip into the single digits. Temperatures remain mostly in the 30s and 40s through the rest of the forecast period. The forecast appears mainly dry through Saturday with only minimal chances for precipitation. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 537 PM CST Sat Dec 28 2019 A wintry mix will slowly change over to all snow tonight. Snow will lead to reductions in visibility down to a mile at times in heavier snow bands. Gusty northwest winds are also a concern through Sunday night as strong winds could cause blowing and drifting snow. && .LBF WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning until 6 PM CST /5 PM MST/ Sunday for NEZ004>010-022>029-035>038-056>059-069>071-094. && $$ SHORT TERM...Gomez LONG TERM...Gomez AVIATION...Kulik
lift, as mentioned in our previous short range forecast discussion.

&& .Short Term...(Tonight through Sunday evening) Updated at 315 PM EST Sat Dec 28 2019 SFC boundary draped along the Ohio River will continue to push northward as a warm front this afternoon and overnight in response to the developing SFC low strengthening over the central Plains this afternoon. Initially this evening, outside of a few sprinkles or scattered light rain showers, we will be mostly dry and overcast through the evening. Overnight, as a strong LLJ moves over the region, our PoPs increase with more widespread rain showers moving into the area during the predawn hours. It will also remain very mild for this time of year with lows in the mid to upper 50s. Very warm and moisture laden airmass will continue to be in place for Sunday. The first wave of rain diminishes some before midday before the second wave of heavier rain arrives in the afternoon into the evening with PWAT values reaching 1.4 to 1.6 inch range. With the heavy rain there is a chance of isolated embedded thunderstorms. SPC has the southern half of our CWA in a Marginal Risk. Total QPF from this event continues to be between 1.00 to 3.00 inches. Collaborating with our neighbors a Flood Watch has been issued for all our CWA. Could have some minor flooding during the event along with some river flooding later next week in the Kentucky, Salt, Rough, and especially Green River basins. Temperatures remain unseasonably warm as highs Sunday, even with the clouds and rain, could approach the middle to upper 60s. These highs are just a few degrees below record highs for SDF, BWG & LEX. && .Long Term...(After midnight Sunday night through Saturday) Issued at 310 PM EST Sat Dec 28 2019 Sunday Night through Tuesday Night... Surface cold front is forecast to be moving through the region at the beginning of the forecast period. Widespread moderate to occasionally heavy rainfall will be in progress Sunday night. Heaviest axis of precipitation Sunday night looks to favor our eastern areas before tapering off Monday morning. Sunday evening temperatures will likely be in the upper 50s to the lower 60s, but we`ll see temps fall steadily behind the front with readings falling into the lower-mid 40s by Monday morning. Decent dry slotting should cut into the region on Monday leaving much of the day dry, cool, and windy. Highs will likely only top out in the upper 40s to around 50 with lows in the lower 30s. Winds of 10-20 MPH with gusts to 30 MPH at times will be possible. A northwest flow will be seen Monday night with a slot of lower-level moisture pivoting in from the northwest during the day on Tuesday. A decent swath of light snow and/or flurries will be seen primarily across northern/central IL/IN and Ohio, with some snow flurries affecting portions of SE Indiana and some of our northern counties in the Bluegrass. Highs Tuesday will range from about 40 in southern Indiana and northern Kentucky to the lower-mid 40s over far southern KY. Lows Tuesday night and ringing in 2020 will be in the upper 20s. Wednesday through Saturday... Closed upper low over the eastern Great Lakes will slowly pivot through New England as we head into the mid-week time frame. Late Wednesday we`ll see a developing trough axis out across the western US with this trough digging a bit as it comes across the central Plains by late week. Strong S/SW flow out ahead of this trough will bring another surge of milder temps and moisture back into the region for Thursday/Friday and possibly into Saturday. There remains some differences in the track of that system. Yesterday`s and today`s Euro runs are still suggestive of a stronger, more westward tracking system that would bring another bout of heavy rainfall to the region. The CMC and GFS solutions are a little more progressive and a bit further to the east. Using an ensemble approach here of all three models will keep good continuity within the ongoing forecast; which would still feature a high chance of rainfall from Thursday afternoon through Friday night. Highs Wednesday will range from the lower-mid 40s over southern IN and northern KY to the upper 40s to around 50 down near the KY/TN border region. Warmer temps are expected for Thursday-Saturday with highs in the low-mid 50s with overnight lows in the upper 30s to the lower 40s. && .Aviation...(00Z TAF Issuance) Issued at 645 PM EST Sat Dec 28 2019 All TAF sites currently are VFR with an east-southeast surface wind of 5-10 kts. NWS Doppler radar shows scattered showers affecting BWG at this time, and they will affect SDF by 01 UTC. With a storm system to our west, rainfall coverage will increase late tonight/ overnight as surface winds begin to increase from the southeast, eventually becoming southerly by or before 12 UTC at most sites with gusts near 20 kts. Ceilings and vsbys will become MVFR overnight with IFR ceilings possible at HNB starting roughly around 09 UTC. On Sunday, a steady rain (moderate-heavy at times) will occur across a good portion of central KY and south-central IN, including all TAF sites, with an embedded thunderstorm possible. Ceilings should generally be IFR but be low MVFR at times, with generally MVFR vsbys. Surface winds will continue gusty from the south at 20-25 kts. Models suggest rain and associated lower ceilings may improve temporarily at HNB Sunday afternoon before another surge of moisture affects the region late Sunday and during the evening. Surface winds should start to veer to the southwest and diminish to about 10 kts near the end of the forecast period at most TAF sites. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...Flood Watch through Sunday evening for INZ076>079-083-084- 089>092. KY...Flood Watch through Sunday evening for KYZ023>043-045>049- 053>057-061>067-070>078-081-082. && $$ Update...TWF Short Term...BTN Long Term...MJ Aviation...TWF
Area Forecast Discussion
National Weather Service Nashville TN
717 PM CST Sat Dec 28 2019 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... Current radar imagery is showing a lull in shower activity early this evening, and the latest HRRR suggests only scattered cells until closer to 12Z tomorrow morning when showers will increase from the west as a cold front nears the mid state. At this time, a deep surface low is centered over eastern KS, but this system will race eastward during the next 24 hours. The 00Z sounding from OHX shows a stable atmosphere still in place (zero CAPE, +4 lifted index). But the precipitable water has increased to 1.20 inches, which puts us well above the 90th percentile climatologically for this time of year. In addition, 850 mb winds have increase to 30 kts, and low-level winds will continue to increase during the next several hours. So both the moisture and moisture transport are becoming established. Overnight QPF is relatively low. The heaviest rain won`t really set in until after 18Z tomorrow. Current grids are holding up well thus far. Don`t anticipate much of a change to the forecast this shift. && .AVIATION... 00Z TAF DISCUSSION. BNA/MQY/CKV/CSV...Scattered showers are moving northward across Middle Tennessee late this afternoon but should not affect the terminals. The latest HRRR shows surprisingly little activity across the mid state this evening and overnight. The heavier showers won`t settle in until tomorrow. So look for ceilings to lower to MVFR after 06Z with mainly light showers. Am including LLWS remarks at CKV/CSV owing to an increase in the LLJ later tonight & tomorrow. LLWS criteria should be met at these two terminals. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......08 AVIATION........08