Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/08/19


Area Forecast Discussion
National Weather Service Dodge City KS
607 PM CDT Tue May 7 2019 ...UPDATE TO AVIATION... .SHORT TERM...(This evening through Wednesday) Issued at 320 PM CDT Tue May 7 2019 Precipitation efficiency should be even greater this evening as the Precipitable water values in the layer have increased considerably from last night, to as much as 1 inch as far west as the Colorado line. The unstable airmass will continue to produce scattered showers and thunderstorms over the entire forecast area, before stronger forcing arrives this evening - spreading excessive rainfall over the central Kansas counties, to the north of the surface warm front. Severe weather threat will mainly hinge on the northward surge of warm air, if any as the forcing increases this evening. If the front doesn`t lift north, the main threats might be limited to heavy rain and hail, but become more of wind or even tornado threat with any northward lift of the frontal zone. At a minimum, the region around Comanche Barber and Pratt counties should logically have the highest severe risk. RAP and HRRR produce widespread 2 to 3 inches rainfall amounts across portion s of the central Kansas counties (fairly regulated to the areas with the current flash flood watch). The southwest upper low lifts into Kansas as a damped out wave in the base of a progressive trough, lifting to the northeast Wednesday night. .LONG TERM...(Wednesday night through Tuesday) Issued at 320 PM CDT Tue May 7 2019 A cooler period is expected with temperatures limited to the 50s (maybe as cold as upper 40s in west central Kansas) for Thursday. Lows will plummet into the 40s Thursday morning and 30s by Friday morning. Only a slow recovery in temperatures is expected through the weekend with highs reaching normal mid may high values of the mid 70s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 605 PM CDT Tue May 7 2019 Scattered thunderstorms will continue to spread northeast across southwest and central Kansas tonight affecting KHYS and KDDC and possibly as far west as KGCK and KLBL. MVFR/IFR cigs/vsbys are expected in the vicinity of all TAF sites through early Wednesday morning as low level stratus persists along and north of a near stationary frontal boundary stretching from the Oklahoma northeast into south central Kansas. East-northeast winds 10 to 20kt will persist north of the aforementioned frontal boundary through late this evening with winds becoming more light and variable overnight as a surface low lifts northeast across southwest and central Kansas. && .PRELIMINARY POINT TEMPS/POPS... DDC 55 68 40 52 / 100 30 20 20 GCK 50 61 40 51 / 90 40 20 20 EHA 50 63 39 51 / 70 30 30 30 LBL 52 66 41 53 / 90 20 20 20 HYS 51 64 40 53 / 90 60 30 20 P28 58 73 45 55 / 100 30 20 10 && .DDC WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through Wednesday evening for KSZ046-064>066- 078>081-087>090. && $$ SHORT TERM...Russell LONG TERM...Russell AVIATION...JJohnson
Area Forecast Discussion
National Weather Service Des Moines IA
650 PM CDT Tue May 7 2019 .DISCUSSION.../Tonight through Tuesday/ Issued at 407 PM CDT Tue May 7 2019 Tonight into Thursday...Main forecast concern remained focused on this period with a strong surface low pressure and associated warm frontal boundary providing an increase in the potential for severe weather Wednesday afternoon and evening. On the contrary, this has decreased the flooding potential with the bulk of the rain pushing further north. The latest model runs continue to trend further north with the surface low track tomorrow placing a good portions of the CWA within the warm sector. A nice slug of theta-e advection within the WAA regime brings in a large rain shield overnight tonight through the morning hours Wednesday. From the latest HRRR/ESRL HRRR runs and even the 07.12z HREF, the rain looks to be as far north as Highway 20 by around 15-17z Wednesday. Certainly plenty of time for destabilizing to occur across southern Iowa into the afternoon hours. Redevelopment looks to be between 19-23z, mainly along and east of I-35 in the southeast portion of the forecast area. Severe weather type looks be mainly damaging wind and tornadoes in the aforementioned location in southeast Iowa where strong deep layer shear, impressive low-level SRH (150-300 m2/s2), and LCLs lowering to under 500-750 feet by the afternoon. Plus, the surface dew points increase into the lower to middle 60s over southern Iowa as the warm front surges northward tomorrow. Forecast soundings suggest good backing winds through the profile (i.e. OTM), especially in the vicinity of the warm front. Certainly the threat (of tornadoes) is conditional if southeast Iowa can destabilize just enough to get updrafts to develop. Agreed with the further north extent of the Slight Risk. Thursday through Friday...surface high pressure builds into the region during this time and even though the time frame for radiational cooling is limited early Friday morning, have introduced mention for frost. Saturday into Tuesday...fairly quiet weather over the weekend with only a weak clipper system to bring light rain showers Saturday night into Sunday. A gradual warming trend during this period and the state looks to be back near normal by Monday. && .AVIATION.../For the 00Z TAFS through 00Z Wednesday evening/ Issued at 650 PM CDT Tue May 7 2019 Cigs to become MVFR with local IFR aft 04Z. Expect SHRA to develop aft 09Z with isold to sct TSRA aft 12Z. Should get a break in precip and possibly cigs aft 17Z through 21Z then TSRA and lowering cigs should redevelop along/east of I-35. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...Podrazik AVIATION...FAB
Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
1005 PM CDT Tue May 7 2019 .UPDATE... The inherited short term forecast is in really good shape, with just a few changes needed. At this time, I still expect a robust line of thunderstorms to move through most of North and Central Texas. Accompanying this line of storms will be a threat for damaging winds and severe caliber hail (perhaps to 1"). The potential for a couple of QLCS tornadoes cannot be ruled out, but there are some questions regarding this threat. There will be the potential for some gusty to strong non-convective winds ahead of the squall line tonight...especially across the Big Country and parts of Central Texas. Ongoing showers and thunderstorms across Central Texas have persisted this evening as WAA/moist advection---manifest by increasing stratus in the GOES nighttime RGB---continues. Given the paltry deep layer shear, this activity is largely unorganized, and these showers/storms will pose more of a heavy rain and gusty wind threat. Convection across western Oklahoma continues to organize some and will spread eastward with time. There will be the potential for backbuilding as strong 925mb low level flow--- already AOA 35 knots per area VWP--ramps up. A new batch of convection will likely develop in western North Texas and as this feature unzips southward through the Hill Country, the increasing shear and sufficient instability should foster a large line of showers and thunderstorms. The better overlap of shear/instability will be near and north of I-20 and near and west of I-35. Damaging straight line winds will be the main hazard as 0-1 km flow increases and should provide some decent momentum to transfer down to the surface. 700-500mb lapse rates near 7.5 C/km will promote some marginally severe hail risk as well. 0-1 km shear vector magnitudes are forecast to be on the order of 20 to 30 knots which would support QLCS tornadoes...however...flow in the 2 to 3 km layer drops substantially and this casts some doubt on the overall QLCS tornado risk. IF the 2 to 3 km flow can increase some and/or low level flow backs...the QLCS tornado threat may increase. There will be a risk for Flooding/Flash flooding...especially for water-logged areas along and north of the US HWY 380 corridor. At this time, I feel that the speed of the convective complex will mitigate the necessity for a Flash Flood/Flood Watch. IF the complex slows, there could be a more appreciable Flood/Flash flood risk. Main stem river flooding will likely continue given the status of area lakes. Given the confidence in the probability that storms will occur, I`ve nudged PoPs upward with 100 PoPs north of I-20 after 0600 UTC Wednesday. With the 0-1 km flow increasing, we will need to monitor the potential for strong to possibly severe pre-squall winds around the 0800-1200 UTC time frame west of I-35. I`ve increased the winds and wind gusts areawide as the latest HRRR and NAM NEST explicit wind gusts forecasts suggest near High Wind Warning criteria (again mainly across the Big Country). For now, I`m not inclined to go with any NPWs after discussion given these models tendency to inflate wind speeds/gusts, but it`s not out of the realm of possibility to see non-convective wind gusts to near 50 knots ahead of the main line. The convective forecast remains largely unchanged after 12 UTC Wednesday with the expectation that by this time a large line of showers/storms (some storms may be severe) will be nearing the I-35 corridor. Areas east of this line during the mid-morning to early afternoon hours on Wednesday will have the potential for a slightly greater threat for severe weather thanks to additional moisture advection and daytime heating. More details on this will be forthcoming with the overnight forecast package. Bain && .AVIATION... /Issued 716 PM CDT Tue May 7 2019/ /00 UTC TAF Cycle/ Concerns---Convection across D10 TRACON at current time...return of MVFR stratus...and TS during the Wednesday AM push (likely substantial impacts to D10 airspace). Isolated convection continued to briefly develop along a northwestward moving outflow boundary across the Metroplex TAFs. While I cannot rule out an isolated lightning strike or two, this potential is too low to continue to mention VCTS in the TAFs and have replaced this with VCSH for through 0200 UTC. The outflow boundary may kick up some winds...with gusty winds to near 25 knots. Waco resides southeast of this boundary and the risk for any rain/storms this evening remains very low. MVFR stratus will surge northward overnight, though I have delayed the onset by a couple of hours. Though the complex of storms across the Gulf of Mexico will decay by midnight, the wind field associated with this may change moisture trajectories into North and Central Texas. As such, MVFR stratus likely won`t make it into Waco until around 0500 UTC and into the Metroplex closer to 0700 UTC. The IFR potential (outside of thunderstorms) is low, but non-zero...especially at Waco. For now, I`ll abstain from mentioning this and examine it in subsequent TAFs. The main show will be a line of strong to possibly TS rolling through area terminals. All indications are that activity should encroach from the northwest and move eastward across most of North Texas. This will result in substantial impacts to just about all cornerposts and departure routes. VCTS at all D10 terminals is expected between the 12 and 17 UTC....with a 3 hour TEMPO TSRA group from 13-16 UTC. There will be a risk for a wind shift to the northwest associated with TS along with wind gusts to near 30 knots...though higher gusts will be possible. A small hail threat will exist, but confidence to include in the TAF is too low. TS at Waco will be a few hours later with strong winds expected with TS. Erratic and variable winds are possible a few hours after TSRA, but south to southeast surface winds will return in the afternoon hours. South winds could gusts as high as 25 knots. Bain && .SHORT TERM... /Issued 322 PM CDT Tue May 7 2019/ /Tonight/ Main concern through the late afternoon and evening hours will be thunderstorm potential generally east of I-35 and south of I-20. Convection across southeast Texas has slowly drifted to the north this afternoon into southeast parts of the forecast area. Latest SPC mesoanalysis paints MLCAPE values around 2500 J/kg across the area. As these storms slowly drift to the north, strong thunderstorms will be possible and can`t completely rule out a few severe storms through the early evening hours. The main hazards would be large hail and gusty winds if a severe storm threat were to materialize. A low, end isolated flooding threat could develop as well due to higher rainfall rates and/or any training of storms. Latest CAMs in decent agreement that shower and storms will diminish with the loss of daytime heating, and will continue with low pops through 03z. Attention will turn to the west for tonight into early Wednesday morning. Thunderstorms have all ready erupted this afternoon across the Texas Panhandle and South Plains along the front and dryline. As the evening progresses, thunderstorms will begin to march eastward and develop into a squall line. These storms will enter the west and northwest parts of the forecast area overnight, likely between 3am and 5am. By the end of the period, the complex may be approaching the Metroplex. Main threat with the storms will be damaging winds, however a low, non-zero tornado threat may exist within the squall line. Lastly, some locally heavy rain will be possible along the Red River overnight which may result in some minor flooding issues due to the recent rains and saturated soils. && .LONG TERM... /Issued 322 PM CDT Tue May 7 2019/ /Wednesday through Next Week/ A shortwave should be crossing the Texas panhandle on its way into the Southern Plains at the start of the period. Convection associated with this feature will have likely already developed upscale into a QLCS, with recent guidance indicating that these storms will be encroaching on the I-35 corridor around daybreak. The pre-storm environment indicates that a severe storm threat will exist along the line with damaging winds the primary concern. However, brief spin-up tornadoes will also be a possibility, particularly if we get any backing of the surface winds ahead of the line of storms. In addition, even though activity should be progressive in nature, PWATs in the 1.50 to 1.75 range will make localized flash flooding a possibility due to recent rains and saturated soils. This would be most problematic if training storms occur or if the line of storms slows its forward progress at any point. A weakening trend may occur as activity pushes farther south and east due to the better forcing for ascent lifting northeast of the region as the shortwave heads for the Midwest. That said, due to better instability in place, strong to severe storms will remain possible across the southeasternmost counties with large hail and damaging winds possible. A second shortwave disturbance is progged to move across northwest Texas late tomorrow night into Thursday. This may ignite another round of showers and storms late Wednesday into early Thursday. Activity will be limited to areas east of the I-35 corridor and should be less coverage than the previous round. A strong or severe storm cannot be ruled out, though the environment will be less favorable having recently been scoured by the Wednesday activity. A cold front will then push through the region on Thursday as the shortwave races off to the east. Additional convection along the front may briefly affect the far southern zones, but most of he frontal activity will develop south of the region where sufficient moisture and instability will be in place. A cool-down can be expected behind the front, with temperatures falling into the 50s across most of the area (a few upper 40s across the northwest) Thursday night. By Friday, the next upper low will be digging over Southern California. The resulting flow aloft will lead to increasing isentropic lift above the cool surface layer and additional chances of showers and thunderstorms both Friday and Saturday. The Friday precipitation should be focused mainly over the southern half of the region in the vicinity of a weak disturbance embedded in the southwest flow aloft. A second and stronger shortwave will pass across the area on Saturday, producing more widespread precipitation across the region. Thunderstorms will be elevated in nature above the frontal layer, but still may be capable of producing quarter size hail. These additional rains will likely lead to additional river flooding and possible localized flash flooding in heavier storms. At this time, we do not plan on any flood watch products, but may need to consider one in future forecast packages depending on how much rain falls tomorrow. Either way, the presence of clouds and rain will keep temperatures on the cool side both Friday and Saturday with highs in the upper 60s to lower 70s. Precipitation will exit to the east late Saturday as the shortwave swings across the Mississippi Valley. Sunday will therefore be relatively dry and pleasant as a shortwave ridge develops overhead, with lows in the upper 50s and highs in the mid to upper 70s. The West Coast low will finally advance east, reaching West Texas Monday or next Tuesday. This will bring yet another round of showers and storms during the first half of next week. 30 && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 69 79 66 76 53 / 60 80 20 10 20 Waco 70 77 67 78 54 / 30 60 30 20 50 Paris 68 74 66 77 51 / 40 80 50 20 20 Denton 69 79 63 73 50 / 80 80 20 5 10 McKinney 69 76 66 75 51 / 60 80 30 10 20 Dallas 70 79 67 78 53 / 60 80 30 10 20 Terrell 70 76 66 79 52 / 40 80 40 20 30 Corsicana 69 77 66 79 54 / 30 70 50 20 50 Temple 70 78 68 80 54 / 30 70 40 30 60 Mineral Wells 68 82 58 72 50 / 70 80 10 5 20 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 24/79
Area Forecast Discussion
National Weather Service Lincoln IL
831 PM CDT Tue May 7 2019 .UPDATE... Issued at 831 PM CDT Tue May 7 2019 Showers so far this evening have been limited to areas from about Quincy to Danville northward, with skies partly cloudy at times across areas south of I-72. Main cluster of showers and thunderstorms is out over Kansas this evening, though some recent development has been taking place over northern Missouri. This latter activity will keep likely showers over the northern CWA through much of the night. Further south, there has also some recent thunderstorm development over south central Missouri, a bit faster than recent HRRR runs alluded to, though in the correct location. The HRRR expands this activity as it lifts northeast, and will be a threat to the western CWA after 3-4 am. Forecasts were recently updated to update these precip trends. A little downward adjustment in temperatures was needed north of I-74, where temperatures did not get quite as high this afternoon as earlier expected. && .SHORT TERM...(This evening through Wednesday) ISSUED AT 322 PM CDT Tue May 7 2019 The stationary boundary remains planted over south central Illinois this afternoon, allowing a wave system to ride on the northern fringe. This is bringing rain showers to locations north of the I-72 corridor this afternoon, and will continue to bring showers over the next couple of hours. This wave will shift northeast of the area this evening, bringing a brief break in wet weather. Additional rainfall in central Kansas will continue to track northeast, brushing the NWern CWA, mostly impacting northern Illinois and southern Wisconsin overnight. High pressure situated over the northern Great Lakes, will continue to slowly shift out of the region overnight, allowing a Low pressure system in the Rockies to finally start ejecting out into the Plains. This will lift the stationary boundary through central Illinois on Wednesday, as a warm front. Strong southerly winds will return, Wednesday along with an increase in temperatures well ahead of the Low core. As the warm front lifts north, and destabilization of the lower atmosphere occurs, storms are expected to develop along a north- south line and shift through the Midwest Wednesday afternoon and evening. SPC recently upgraded the NWern CWA and west central Illinois into a SLGT Risk for severe thunderstorms during the afternoon. Later forecasts will monitor for the potential of an eastward movement of the SLGT, but that will depending on any potential breaks in clouds that provide sunshine, and how much WAA arrives into the area. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 322 PM CDT Tue May 7 2019 A line of storms is expected to push through the region Wednesday afternoon/evening, as moisture is lifted into the region from the Gulf of Mexico. Once this slides eastward overnight, the Low core will rush into northern Illinois. Winds will remain elevated ahead of the cold front Wednesday night, and continue to gust from the south into Thursday morning for locations in central and southeast Illinois. A second line of storms is expected to slide into southern Illinois early Thursday morning. This line could bring strong storms into southeastern locations, however this will also be a line to watch as diurnal effects could play a substantial role in the strength. As the frontal passage occurs Thursday afternoon, more storms should develop as the atmosphere remains unstable, but the strength of these storms will once again depend on the available destabilization of the low levels. After the front finally pushes east of the region Thursday night, High pressure from Canada will quickly drop into the central US. This will overspread drier conditions across much of the region to end the week, and begin the weekend. Temperatures behind the front will be cooler, with highs in the 60s and lows in the 40s. As the High dominates the Midwest weather, it will also hold a wet weather pattern across the southeast US through the first half of the weekend. Then another Low pressure system will slide from Canada into the Great Lakes region, sinking a cold front with it into the Midwest. Model uncertainty exists with respect to the amount of available moisture for any chance of shower activity on Mother`s Day. This will be monitored with later model runs. High pressure returns at the start of next week and will last through the beginning of the week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 616 PM CDT Tue May 7 2019 Main concern in the short term is with a band of MVFR ceilings north of a stationary front, primarily impacting KPIA/KBMI. Ceilings below 2,000 feet will prevail in this area a good portion of the night, but some improvement will begin late at KBMI as the front begins a northward push. By about 15Z, all sites should be VFR, and winds will be turning to the southeast/south and becoming gusty by midday. Later in the period, a line of showers and thunderstorms will develop and push into western Illinois. Have only included VCTS at KPIA/KSPI at the moment, with areas further east more likely to see this arrive toward 00Z or later. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SHORT TERM...Baker LONG TERM...Baker AVIATION...Geelhart
...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Wednesday) Issued at 211 PM CDT Tue May 7 2019 As of 20Z Tuesday afternoon, an upper low was centered across eastern AZ with cyclonic flow overspreading the Plains. Similar to the previous days, a stationary front is positioned across the forecast area. At this hour, the front extended from east-central NM, northeastward to near ICT, continuing northeastward to just north of EMP and eastward to central MO. An outflow boundary has become diffuse across northeastern OK and latest satellite depicts low-level moisture surging northward into southeastern KS. Two areas of thunderstorm activity have developed with the first across the TX panhandle -- near the triple point, and the second across south- central KS -- along the stationary boundary. To this point, the activity across southern KS has remain elevated and relatively unorganized. RAP forecast soundings depict over the next 1-2 hours that storms should become surface-based as they slowly progress east-northeastward. The biggest question mark over the next 4-6 hours is whether storms can remain surface-based into the area. Latest mesoanalysis suggests upwards of 500 J/kg MLCAPE with little inhibition exists south of the aforementioned boundary across portions of Lyon, Coffey, and Anderson counties. RAP forecast soundings predict continued sfc heating will increase MLCAPE to 1000- 1500 J/kg by 22-23Z across these counties. Albeit weak midlevel winds, sufficient veering through the profile will contribute to 30- 40 kts of effective shear which could poise a damaging wind and hail threat. While effective SRH is progged to near 200 m2/s2 along the boundary this afternoon/evening, surging cold-pools should should largely limit the tornado threat. As nocturnal cooling ensues this evening, these storms should weaken. Our attention then turns to the TX panhandle region where thunderstorms have developed. Short term solutions progress this thunderstorm activity east-northeastward along the aforementioned surface boundary into portions of southern KS. In addition, an MCV is progged to develop as the MCS progresses eastward. This MCV combined with a strengthening LLJ should allow for MCS maintenance into the CWA late this evening into the overnight. Generally MUCAPE is progged to range from 800 to 1100 J/kg, from north to south across the forecast area. Effective shear within the elevated layer is forecast to range from 40-50 kts, which should limit the ability for cold-pools to surge well-ahead of updrafts. Forecast soundings are progged to remain largely coupled through the evening/overnight, as a result damaging winds are possible with the MCS through the night, especially along and south of I-70. Flash-flooding could become a concern with most areas having 1 hour flash-flood guidance near 1" and 3 hour guidance near 1.5". Using a persistence forecast from the past 2 days, the strongest storms were producing hourly rainfall rates exceeding 1". Subsidence behind the MCS/MCV will likely decrease shower/storm coverage by mid/late Wednesday morning. Transitioning into Wednesday afternoon, the main upper low is progged to eject into the southern and central Plains. Deepening of the lee cyclone will lift the front back northward with its position from the TX panhandle northeastward into far northeast KS. By mid to late afternoon, guidance suggests 1500-2500 J/kg of MLCAPE will reside along and southeast the boundary. Effective shear values near 40 kts will foster organized updrafts. Initial convective mode should be supercellular with eventual upscale growth into an MCS. Large hail and damaging winds will be the primary hazards with the strongest storms. Furthermore, the flood/flash-flood threat will persist through Wednesday night with an additional round of heavy rainfall. .LONG TERM...(Wednesday night through Tuesday) Issued at 211 PM CDT Tue May 7 2019 Beyond Wednesday, a much quieter weather patter will ensue with surface and midlevel ridging overspreading the central Plains. Temperatures will slowly moderate through the remainder of the week with highs on Thursday only in the 50s. Temperatures are likely to return to the 70s by the weekend. Friday morning temperatures will be quite cold with lows in the upper 30s and lower 40s. The next chance for rainfall arrives Sunday as a northern stream trough traverses the northern Plains and drags and attendant surface cold front through the area. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 657 PM CDT Tue May 7 2019 Low end VFR to MVFR conditions expected before the main wave lifts out into central Kansas, developing a swath of TSRA. Short term models prog this activity to bring IFR conditions to terminals in the 04Z-06Z time frame. Gusty easterly winds veer towards the south at KTOP/KFOE with more vrb winds at KMHK as the sfc low passes overhead. Activity gradually ends west to east by 15Z. Additional scattered TSRA is possible towards the end of the forecast period. && .TOP WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through late Wednesday night for KSZ008>012- 020>024-026-034>040-054>056-058-059. && $$ SHORT TERM...Baerg LONG TERM...Baerg AVIATION...Prieto