Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/12/19

Area Forecast Discussion
National Weather Service Charleston SC
923 PM EDT Tue Jun 11 2019 .SYNOPSIS... Low pressure will track along a stalled front over our area from tonight into Wednesday. Another front will sweep through Wednesday night, followed by drier high pressure into the weekend. As the high shifts east over the weekend, a more typical summertime pattern will return. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... This Evening: Latest EMC RAP analysis from SPC shows PWATS of at least 2.25 inches pooling across Southeast GA bands of convective rains persist, resulting in periods of heavy rains with pockets of torrential downpours ongoing along the lower Savannah River region of the forecast area. We will continue the Flash Flood Watch in place on this update package. Overnight, parameters are coming together for additional heavy rainfall further up the coast as low pressure organizes along the stalled front and propagates to the northeast. Strong moisture convergence ahead of the low in the vicinity of the front coupled with high PWATS and lingering nocturnal instability will support a corridor of moderate to heavy rainfall extending from the Georgia coast north into the Charleston Metro Area, including Savannah and Beaufort. High resolution guidance are similar in showing the heaviest rains falling in the Savannah to Charleston corridor with general rainfall amounts of 2-5 inches with some members showing amounts in excess of 6 inches. Although flash flood guidance values are still somewhat high and D1-D2 drought conditions linger, the high PWATS within a weak steering flow environment suggest the resulting convection will be efficient in rain production which could overtake the 1-hr and 3-hr flash flood guidance values. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Wednesday: The mid-levels will consist of a trough building towards the East Coast. At the surface, a stationary front will spread from southwest to northeast over our area. A cold front is expected to follow this front northward with time, starting out over GA during the morning hours and then moving over SC during the afternoon hours. Deep moisture is in place with PWATs over 2", which is well above normal. Models are in good agreement showing widespread showers across our area during the day. There is some instability, so thunderstorms are also possible. But the severe risk is low. The slow motion of the storms and the deep moisture will lead to periods of heavy rainfall with QPF exceeding 1". Some areas could receive more, especially if thunderstorms stay over the same area. This certainly could cause flooding in the typical areas. But if too much rain falls in too short a time, flash flooding cannot be ruled out. Hence, the Flash Flood Watch continues into our time period. The rainfall will wind down from southwest to northeast from the late afternoon through the night as the low moves away. Additionally, a cold front from inland will approach the area, helping to push the moisture away. Expected remnant showers along the coast by daybreak Thursday. Thursday and Friday: A much different pattern is expected both of these days as high pressure builds towards the area. Drier conditions are expected with the high along with fair weather. Highs both days will generally be in the 80s. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... High pressure will maintain dry weather into Saturday before we return to a more typical summertime pattern by Sunday as the high builds off the coast. Temperatures and dewpoints will be back near normal by Sunday, along with scattered showers and tstms each day. && .AVIATION /01Z WEDNESDAY THROUGH SUNDAY/... KCHS: It appears showers will linger in the vicinity of the terminal through the evening with the risk for isolated heavy showers. The chances for showers and tstms should increase as convergence builds along coastal areas after midnight into Wednesday as a wave of low pressure approaches. Periods of flight restrictions are likely in periods of rains and lower clouds. KSAV: Showers and tstms appear likely during the evening hours as strong level moisture convergence ongoing after dusk this evening. Showers and tstms may focus more up the SC coast late tonight, then convective rains should fill back in on Wednesday as an area of low pressure approaches from the southwest. Deep moisture will persist and and periods of flight restrictions are likely with passing convective rains. Extended Aviation Outlook: Flight restrictions will come to an end Wednesday night as high pressure builds into the area. VFR will then prevail. && .MARINE... Tonight: East to southeast winds will prevail as low pressure approaches from the southwest. Speeds will average 10-15 kt with seas 2-3 ft. Stronger flow will reside along the border with the South Santee River Entrance area where speeds may reach 15-20 kt overnight as the pressure gradient pinches between high pressure north and developing low pressure to the southwest. Gusty winds and heavy rainfall dropping vsbys to 1 NM will be possible where areas of heavy rain develop. Wednesday through Saturday: A cold front moving through the area late Wednesday will increase the surface pressure gradient, causing winds to become gusty. However, it appears wind gusts will stay just below our Small Craft Criteria of 25 kt. High pressure will build towards the area Thursday into Friday. Over the weekend our area will return to a more typical summertime pattern with the sea breeze during the day. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...Flash Flood Watch through Wednesday afternoon for GAZ100-101- 114>119-137>141. SC...Flash Flood Watch through Wednesday afternoon for SCZ042>045- 047>052. MARINE...None. && $$ NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE...
Area Forecast Discussion
National Weather Service Lincoln IL
836 PM CDT Tue Jun 11 2019 .UPDATE... Issued at 836 PM CDT Tue Jun 11 2019 Scattered mid level clouds linger over the area this evening, as high clouds edge in from the west. Main area of rain is still southwest-northeast across Iowa, extending southwest into Kansas. Our evening sounding is quite dry, and upstream at the Quad Cities, their sounding is also dry below about 12,000 feet. So, it will take a bit of time for our atmosphere to moisten up, given that dew points fell into the 30s and 40s earlier this afternoon. Tweaked the arrival time of the rain a bit overnight and mainly emphasized the areas west of the Illinois River, though the latest HRRR wants to hold it off until later into Wednesday morning. Temperatures needed some minor adjustments, but are generally on track. && .SHORT TERM...(This evening through Wednesday) ISSUED AT 335 PM CDT Tue Jun 11 2019 Mostly sunny skies and winds less than 10 mph prevailed this afternoon across central and southeast IL. Nice weather today compliments of 1022 mb high pressure over lower MI and western Ohio. Temperatures at 3 pm were mostly in the lower 80s, with a few upper 70s in eastern IL. Low dewpoints of 35-45 degrees over central IL and mid to upper 40s in southeast IL. High pressure will slip off to the east over NY/PA overnight while an mid/upper level trof digs into the Midwest and drives a cold front se toward the IL/IA border by 7 am Wed. Dry conditions expected to continue over CWA this evening, then have chances of showers moving into the IL river valley from I-55 nw during overnight. Isolated thunderstorms possible toward dawn far nw. Mid/upper level trof dig into IL by sunset Wed while a cold front pushes se to near the IL river by 18Z/1 pm Wed and sweep thru central and southeast CWA during Wed afternoon. Have chances of showers and some thunderstorms spreading se with the front during the day, though likely not reaching the Wabash river valley until mid to late Wed afternoon. SPC day1 outlook keeps marginal risk of severe storms sw of CWA over central/southern MO on Wed afternoon and also from Dayton OH to Bowling Green KY east where better instability will be Wed afternoon/evening. Rainfall amounts do not look too much due to limited instability and lift over our area. Lows tonight in the upper 50s to around 60F, except mid 50s east of I-57 and in southeast IL. Highs Wed range from around 70F over the IL river valley, to the upper 70s near the Wabash river. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 335 PM CDT Tue Jun 11 2019 The upper level trof near IL will keep a good chance of showers and some thunderstorms around early Wed evening, then diminishing from the west after sunset Wed night, with most of the convection east of area overnight Wed night. Have just isolated showers near the IN border overnight Wed night into Thu morning. Return of sunshine during Thu with nw breezes, and highs in the lower 70s, with some upper 60s ne of I-74. 1020 mb high pressure moves east into the mid MS and TN river valley during Thu night, bringing fair skies and lighter winds. A cool night in store Thu night with lows in the lower 50s, with some upper 40s possible. Another nice day expected on Friday as high pressure drifts off the southeast Atlantic coast Friday afternoon. Expected partly to mostly sunny skies, sw breezes and milder highs in the upper 70s across central/se IL. The 12Z forecast models continue to show an unsettled weather pattern over the area from Friday night through Mon evening as a frontal boundary moves into the area this weekend. The first disturbance will track into the area during Friday night, spreading chances of showers and some thunderstorms with highest pops overnight Fri night into Sat morning where likely pops are. Convection chances become more scattered by Sat afternoon, but ramp up again during Sat night with next disturbance and low level jet. Heavier rains possible Sat night across area. Yet another round of convection expected Sunday afternoon and Sunday night, as heaviest qpf is shifted into southeast IL. The frontal boundary to shift se toward the Ohio river valley Mon and shifting higher pops into southeast IL by then. Total rainfall amounts from Fri night thru Mon evening range from 1-3 inches over central IL (lowest nw of IL river), with higher amounts of 3-4 inches possible se of I-70. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 613 PM CDT Tue Jun 11 2019 Main forecast concerns come after about 10Z, as ceilings lower ahead of a cold front. Showers and scattered thunderstorms will be approaching KPIA toward 12Z or so, and reaching KCMI by 18-19Z. Some of the forecast guidance suggests ceilings below 3,000 feet close to KPIA/KSPI by early afternoon, before rising a bit immediately ahead of the front. Will include a TEMPO period at KPIA for now, but hold off elsewhere with greater uncertainty. Coverage of thunder is low enough to preclude a mention at this time, but will re-evaluate for the next TAF set as the evening models arrive. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SHORT TERM...07 LONG TERM...07 AVIATION...Geelhart
National Weather Service Jackson KY
1048 PM EDT Tue Jun 11 2019 .UPDATE... Issued at 1048 PM EDT TUE JUN 11 2019 Forecast remains in good shape late this evening, with only minor updates needed to freshen up the near term temps, dew points and winds. Latest observations were already fairly well on track with the forecast. Scattered thin high clouds continue across much of the CWA as well. Still expecting these to increase in coverage throughout the overnight. All updates were published and sent to NDFD/web. A new set of zones was also sent out to change to overnight wording. UPDATE Issued at 742 PM EDT TUE JUN 11 2019 A few changes made over the last couple of hours. First, with ongoing high clouds cover across much of the CWA, went ahead and bumped up sky cover to scattered for this evening, increasing to broken late in the night. Also, while convection is favored for tomorrow, the likelihood for 100 percent coverage in such an environment is not bumped pops down to around 80. This matched up better with neighboring offices, and still conveys the likely to widespread wording. Finally, to make sure the near term forecast was on track with the current conditions, the latest observations were loaded in. This resulted in only minor adjustments. All updates have been published and sent to NDFD/web. A new forecast package will also be sent to reflect these changes. && .SHORT TERM...(This evening through Wednesday night) Issued at 435 PM EDT TUE JUN 11 2019 High pressure is solidly in control across the region today, providing a very pleasant day with pleasant temperatures and low humidity. The surface ridge will exit to the east tonight with return flow developing across the area into the day Wednesday. Surface moisture is expected to recovery quite quickly on Wednesday as a shortwave trough pushes into the region. Strong positive vorticity advection ahead of the trough will across Kentucky leading to shower and thunderstorm development across the area through the day. A few sporadic showers may be possible as early as 8 or 9 am in our southwestern zones as the moisture advects into the area. Better rain chances will come in late morning into the mid afternoon hours. We are in a marginal risk for severe storms on Wednesday, with lots of uncertainty revolving around the marginal risk. First, we will have lots of cloud cover and that could limit potential heating and instability. Second, the flow will be southeasterly (downslope flow)across much of the area which may keep dewpoints from reaching the low 60s, which is where they would need to be to even have a chance at 1000-1500 J/kg MLCAPE. However, there may be a better shot at the moisture getting into our far southern zones (Bell, McCreary, Whitley counties). The 18z HRRR does show some updraft helicity swaths across our southern zones, which has trended more aggressive from the 12z HRRR. We have pretty good shear over the region tomorrow, both directional and speed. Thus, with developing convection it may be possible to sustain some organized updrafts. The low level shear could even briefly be supportive of a brief spin up tornado with the sig tor parameter on the HRRR getting close to 1. Due to the low confidence on instability, opting to stay away from mentioning any tors in the HWO for now. The better threat will remain gusty winds and hail. .LONG TERM...(Thursday through Tuesday) Issued at 435 PM EDT TUE JUN 11 2019 Scattered rain showers will remain across the area into Thursday afternoon as the mid/upper level trough continues to push east across the area, with lingering moisture over the area. Did remove thunder for Thursday as instability is much weaker on the 12z model runs. A surface ridge will spread east across the area Friday into Saturday, providing another drier stretch of weather. With the ridge sliding east this weekend, return flow will allow heat and humidity to return to the region. The weather will also turn more unsettled late Saturday through Tuesday as the upper level flow flattens out and trends more towards zonal flow. However, several shortwaves may take aim on the area from Sunday into Tuesday keeping the weather very unsettled. Forecast will will be very wet and could see some local flooding issues at some point early next week, but too far out at this time to have any kind of confidence on the setup. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) ISSUED AT 748 PM EDT TUE JUN 11 2019 VFR conditions are expected throughout the night and into the morning. High clouds are currently in place and will likely continue through the night, thickening as we head into the day Wednesday. Light and variable winds will also be present during the overnight. However, during the day Wednesday, another cold front and center of low pressure will begin approaching the area. This will lead to an increasing chance of showers and thunderstorms throughout the day, with best coverage expected during the afternoon and evening. MVFR CIGS will be present at times, mainly during mid-day, and any heavier shower or storm could also result in the temporary reduction of VIS. Otherwise, expect winds to remain light and variable, though can`t rule out a storm producing a few gusts. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JMW SHORT TERM...KAS LONG TERM...KAS AVIATION...JMW
Area Forecast Discussion...UPDATED
National Weather Service Norman OK
1004 PM CDT Tue Jun 11 2019 .UPDATE... Main update was to tweak PoPs for the overnight period. Most model solutions continue upscale growth of storms into central and southern Oklahoma overnight. While deep layer shear remains strong, instability will be lacking. With relatively steep lapse rates and shear, we could still see marginally severe hail and wind through the night. && .PREV DISCUSSION... /issued 636 PM CDT Tue Jun 11 2019/ DISCUSSION... The June 12-13 00 UTC TAF discussion follows: AVIATION... A cold front with a northerly wind shift is expected to progress from north to south tonight. Showers and thunderstorms are expected to develop along and move ahead of the front. Brief MVFR ceilings and/or visibilities and gusty winds will be possible with any thunderstorms. Northerly winds and VFR conditions are expected behind the front by later tomorrow morning and through the afternoon hours. Mahale PREV DISCUSSION... /issued 305 PM CDT Tue Jun 11 2019/ DISCUSSION... Main challenge for this forecast period is timing and extent of showers and storms this evening and overnight. NAM and RAP are much slower with the front tonight than the GFS (with the ECMWF holding more of a middle position). Thinking is that the GFS is too aggressive with surface dewpoints resulting in earlier convection. Leaning toward the NAM / RAP solution (also supported by most CAMs) with showers and storms entering northern Oklahoma closer to 4 or 5 Z. These storms will continue overnight with some severe risk as deep layer shear continues around 50 knots and instability decreases slightly. A shortwave moving through may trigger storms off the dryline Thursday afternoon potentially impacting western Oklahoma. Scattered rain chances will continue through early next week with zonal flow. After a relatively cool Wednesday and Thursday, temperatures warm into the weekend. Day && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 61 81 55 77 / 60 20 0 10 Hobart OK 63 83 57 78 / 60 30 10 30 Wichita Falls TX 63 84 60 82 / 60 60 0 10 Gage OK 58 79 53 75 / 40 0 10 40 Ponca City OK 60 78 52 77 / 40 0 0 10 Durant OK 61 83 58 80 / 10 20 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ 11/10