####018004645#### FXUS63 KFSD 100730 AFDFSD Area Forecast Discussion National Weather Service Sioux Falls SD 230 AM CDT Fri May 10 2024 .KEY MESSAGES... - Warm and breezy conditions are expected on Friday, with a very low chance for an isolated shower over Southwest Minnesota or Northern Iowa in the afternoon. - Temperatures remain above normal through the weekend, with highs in the 80s on Sunday combining with a front to produce scattered thunderstorm risks. - Slightly cooler to start next week, with increasing rain chances late Tuesday into Wednesday. && .DISCUSSION... Issued at 222 AM CDT Fri May 10 2024 THIS MORNING: The diurnal drop in temperatures has stalled as mid- lvl clouds within a weak warm advection regime are providing some insulation. However, some sheltered areas in SW Minnesota and NW Iowa may still fall into the lower 40s. TODAY: Mid-lvl clouds will continue to increase through the morning hours as a surface front tracks southeast through the Tri-State area. This front will be pushed through the area by an upper trough moving into the western Great Lakes. A very low chance for a few showers may develop in SW Minnesota into Iowa later afternoon. Temperatures are expected to climb a few degrees warmer than on Thursday, as 850 mb rise ahead of the upper trough. This may likely push temperatures into the lower to middle 70s. The afternoon may be quite breezy with gusts over 25 mph at times. TONIGHT: Skies clear and winds turn light and variable overnight as high pressure moves into the Dakotas. This combination should provide optimal viewing conditions for the potential northern lights show into Saturday morning with space weather forecasts suggesting best viewing from 03Z to 12Z Saturday. SATURDAY: Winds increase through the day on Saturday, turning southwesterly in response to a mid-lvl trough crossing the Northern Rockies. As 850mb temperature rise towards the +11 to +14C range during the day, this should result in widespread highs in the middle to upper 70s. SUNDAY: A frontal boundary approaches the CWA on Sunday as mid-lvl troughing crosses the Dakotas. A fairly weak LLJ early Sunday should lead to scattered mid-lvl clouds, and perhaps a low risk for a few isolated showers in the morning. However slightly higher risks for convection will present themselves along the frontal boundary Sunday afternoon. Depending on the quality of the low-lvl moisture, we may see upwards of 500-800 J/KG MLCAPE ahead of the boundary. Increasing synoptic lift should spark scattered showers and a few thunderstorms into Sunday evening. However, with effective shear only around 10 knots, the greatest risk would be for some high based stronger downdraft winds. Temperatures Sunday may be dependent on mid-lvl cloud cover formation. GEFS/ECM/CMC all indicate probabilities for temperatures over 80, with the Canadian ensemble more bullish areawide and GEFS/ECM suggesting high probabilities focused in the higher elevations. MONDAY-THURSDAY: Weak cold air advection behind the upper trough will lower temperatures slightly on Monday. Though, this cooldown will be short-lived as ridging increases quickly on Tuesday. The next meaningful rain chance moves in late Tuesday through Wednesday heights fall over the High Plains and moisture begins to return back towards the Dakotas. A passing cold front will provide enough lift for scattered storms into Wednesday, though the severe weather risk remains fairly low. Expecting NBM PoPs to continue their slow upwards climb over the upcoming day or two given strong signals in GEFS/ECM probabilities of 0.1"of 70-80%. Only reason PoPs are currently lower is the slight mis-match in timing between the ensemble camps. Temperatures are expected to fall back to seasonal normals Wednesday and Thursday. && .AVIATION /00Z TAFS THROUGH 00Z SATURDAY/... Issued at 546 PM CDT Thu May 9 2024 VFR conditions will prevail through the period. Cumulus will clear out this evening with weakening winds turning westerly. Mid to high clouds spread back in early Friday morning with northwest winds gusting again after sunrise. Expect gusts to peak at 25 to 30 kts Friday afternoon with a low chance of isolated showers east of the Interstate 29 corridor. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && $$ DISCUSSION...Dux AVIATION...BP ####018005677#### FXUS63 KDDC 100731 AFDDDC Area Forecast Discussion National Weather Service Dodge City KS 231 AM CDT Fri May 10 2024 .KEY MESSAGES... - A dry and mild end to the workweek across southwest Kansas. - Forecast trend is becoming more favorable for a wet weather pattern this weekend and next week. - Probabilities of 0.5 inch of rain or more from late Saturday through mid Monday are increasing. && .SHORT TERM /THROUGH SATURDAY/... Issued at 200 AM CDT Fri May 10 2024 06Z surface observations and RAP upper air analysis has a large upper low centered in Utah with west to southwest winds aloft moving through the central plains. An area of PVA and 700 mb shortwave has led to some light rain showers mainly in eastern New Mexico and southeast Colorado. As the rain moves east with lesser moisture at the surface we are just seeing a band of mid level clouds moving into far western Kansas. Boundary layer winds continue out of the north to northeast as a surface high in central Wyoming and the clockwise flow around it is keeping the winds northerly. For today the surface high will slide into eastern Colorado and this will lead to generally light north winds. Periods of mid to high level clouds will move across southwest Kansas as we should see some weak PVA and 700 mb lift across eastern Colorado and southwest Kansas. Highs will reach into the 70s. Tonight we shouldn't see much movement with the upper low as it will still be around the Utah-Arizona border. However southwest winds at 500-700 mb and winds turning east to southeast in west Texas will increase the moisture and upslope flow that we should start to see a band of light rain develop in these regions. Overall Kansas should stay dry as the winds will stay northerly and the bulk of the higher surface moisture will stay to the south. Clouds will be on the increase during the overnight hours and we should see overcast skies in far southwest Kansas by morning. Saturday should start out dry and the latest trends in the short and medium time framed models have the 700 mb low and increasing moisture reaching far southwest Kansas after the noon hour. POPs should increase after 18Z and by 21Z we will have 40-50% POPs for areas from Liberal to Syracuse on west. Low amounts of CAPE will negate any severe threat but there will be enough energy for a few embedded thunderstorms. We could see rainfall totals approaching 0.10 inch in the far southwest by sunset as Euro and GEFS ensembles have 40-70% probabilities of 0.10 inch at Elkhart by 00Z. More details on the widespread rain event for southwest Kansas will be detailed in the long term. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 219 AM CDT Fri May 10 2024 Medium time frame models show widespread light rain overspreading southwest Kansas during the evening and early overnight hours from Saturday night into Sunday as the main 700 mb lift goes from southwest to northeast. Rainfall amounts should be around 0.10 of inch with the initial first round of rain as probabilities of 0.10 are pretty high west of highway 83 at 50-80% and lesser as you go east at 30-50%. This particular system will bring waves of rain as the initial forcing will weaken after midnight and we should see a break in the rain. Sunday morning we should see another round of rain develop as the 700 mb low moves into eastern Colorado and stronger PVA will lead to a deepening low. With greater forcing and ample moisture (forecast dewpoints in the mid 50s) we will see rain increase in coverage and intensity during the day and by mid to late afternoon 6 hour forecast rainfall totals of 0.10-0.50 inch become quite common across southwest Kansas. EPS has near 100% probability of 0.10 inch during the day and 0.50 inch is 50-70% from late afternoon Sunday through Sunday night. This lines up with the closed low slowly moving into Kansas by early Monday morning and the upper level winds are still trending lighter on the south side of the low which would suggest the eastward propagation of the low will be slow. This would be good news for extending amounts of gentle rain across southwest Kansas as the forcing and moisture should keep rain around southwest Kansas at least through noon Monday and perhaps into the afternoon with some rain developing on the backside of the low from Liberal to Hays on east. Total QPF at this point is approaching widespread 0.75-1 inch of rain for southwest Kansas. Severe weather threat will be low however there will be enough energy for a few embedded thunderstorms. Tuesday will be a dry day and then mid week chances of rain increase again (30-40% POPs) on Wednesday. An upper level trough and 700 mb closed low will come out of the northwest and similar to the first system the upper level winds won't be very strong so a slower propagation to the east is the trend at this point. This will keep rain chances into Thursday. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1202 AM CDT Fri May 10 2024 Near 100% probability of VFR flight category for all terminals during the time period. A band of mid level clouds will lower ceilings to around 15 kft through the overnight and mid morning hours. Winds in general will be 5-12 kts sustained with a few gusts as high as 15 kts in the afternoon. && .DDC WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Tatro LONG TERM...Tatro AVIATION...Tatro ####018007552#### FXUS61 KCLE 100731 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 331 AM EDT Fri May 10 2024 .SYNOPSIS... A surface trough over the region today will drift to the eastern Great Lakes by tonight. Low pressure moves across Ontario into New York State on Saturday as a cold front crosses the region from west to east. High pressure briefly builds over Ohio on Sunday before the next weakening cold front moves southward over the region by Monday night. && .NEAR TERM /THROUGH SATURDAY/... Surface low pressure has moved east of the region but we still have an upper level trough that needs to pass overhead through the day. So expect some weak lift to persist across the region through the morning with light rain/sprinkles expected. The rain ends from west to east late this morning into the afternoon with it persisting the longest across NW PA. It then looks to be dry tonight with cloud cover decreasing. It will remain cool today with highs ranging from the mid 50's across the east to the mid 60's across NW OH. The decrease in the cloud cover and light winds tonight should allow temperatures to range from the upper 30's to upper 40's. We will need to monitor for some patchy frost across inland NE OH into inland NW PA. At this point it does not look widespread enough to issue a frost advisory. After a brief period of high pressure over the region Friday night it looks like we will get another fast moving storm system to impact the area. This storm system will be moving through the northwesterly flow with its cold pool of air moving overhead. This should lead to the development of a few thunderstorms along and ahead of a cold front that sweeps west to east across the CWA through Saturday evening. The cold air aloft may end up contributing to hail to develop within the best updrafts. It does NOT appear there will be enough instability in the atmosphere to grow this hail to severe levels. Highs Saturday should range from the mid 50's across NW PA to the lower 60's across NW OH. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... By Saturday night, the aforementioned low pressure system will shift to be centered over the eastern Great Lakes region. This low will continue to drift east overnight as a progressive upper level trough over the Great Lakes brings additional synoptic support to the area. This synoptic support coupled with a relatively cool 850-mb flow of 2-4C across Lake Erie should allow for continued rain showers over far NE OH and NW PA through Sunday morning. All showers should end by late Sunday morning as a nose of high pressure pushes north of the area. Late Sunday into Monday, a boundary will become near stationary north of the area which will act as a focus for additional shower development, keeping much of the area dry into Monday morning. In the meantime, the area will linger in the warm sector of the system, allowing for southwest winds to usher in warmer and more moist air over the area. Showers are expected to become more widespread Monday afternoon as stalled boundary begins to move towards the area as a cold front. Initial forcing will be primarily diurnal instability, but as the front moves east late Monday into Tuesday, frontogenesis coupled with upper level support from a jet stream will result in widespread shower development. With the better forcing, cannot rule out thunder late Monday into early Tuesday. General QPF for late Monday through the overnight hours should remain below 0.2", but higher totals are expected in the long term period. Saturday night lows will remain quite chilly with temperatures dropping into the low to mid 40s. By Sunday night, temperatures will be a mid more mild only dropping into the upper 40s to mid 50s as WAA becomes established across the area. High temperatures will follow a similar trend with highs on Sunday reaching into the mid 60s to low 70s, but will then warm on Monday to reach into the low to mid 70s. && .LONG TERM /TUESDAY THROUGH THURSDAY/... The long term period looks to remain fairly active as another system is expected to move east across the Ohio River Valley through Wednesday night. Models diverge in the exact placement of this low, so opted to maintain slight chance PoPs for much of the area, but any northerly shift in the track will likely result in more widespread showers with greater QPF associated with it. These showers will primarily be supported by an upper level shortwave trough, although models do suggest areas of frontogenetic and isentropic lift. By Thursday, all long range models, including the GFS and ECMWF, have a high pressure system building over the Great Lakes region as an upper level ridge pushes east. Opted to decrease PoPs for the end of the period given the consistency in models, but any shift in timing of the low pressure midweek may result in showers continuing through the end of the period. Highs throughout the period will gradually warm from being in the upper 60s on Tuesday to being in the mid 70s by Thursday. Overnight lows will generally linger in the mid 50s through the period. && .AVIATION /06Z Friday THROUGH Tuesday/... A few area of light rain or sprinkles remain across the region as we wait for an upper level trough to cross the region through the day. VFR cloud covers the entire region but do think there could be some patchy MVFR ceilings where the light rain/sprinkles are most persistent. Otherwise drier air will spread across the region from west to east through the afternoon with ceilings gradually dissipating. Northerly winds of 5-10 knots may become gusty for a few hours through early afternoon. Gusty may reach 20 knots. The winds then decrease by evening as the winds shift to the northwest and eventually to the southwest overnight. Outlook...Non-VFR possible in showers and thunderstorms Saturday into Saturday night. Non-VFR possible on Tuesday in rain showers. && .MARINE... High pressure has gradually begun to push south over the area as a low pressure system gradually departs off the Mid-Atlantic Coast today. This has allowed winds to become north-northeasterly across Lake Erie and weaken to 5-10 knots. As a result, the Small Craft Advisory has been cancelled this morning. Winds will remain light into Saturday before shifting to be southwesterly at 15-20 knots as another low pressure system tracks across the Lake Erie Basin. As the center of the low pushes east, winds will become northwesterly, remaining at 15-20 knots for the central and western basins, but diminishing to 10-15 knots for the eastern basin through much of Saturday night. This will be the next period to keep an eye for the potential of additional marine headlines. High pressure returns on Sunday and allows all winds to weaken from the northwest at 5-10 knots. As another system moves into the area, winds will again become established from the south-southwest, increasing to 10-15 knots late Sunday into Monday. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. NY...None. MARINE...None. && $$ SYNOPSIS...MM NEAR TERM...MM SHORT TERM...Campbell LONG TERM...Campbell AVIATION...MM MARINE...Campbell ####018004520#### FXUS62 KGSP 100735 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 335 AM EDT Fri May 10 2024 .SYNOPSIS... Another system will bring showers and thunder this afternoon, before dry high pressure builds in through the weekend. An active pattern will set in for the new workweek. && .NEAR TERM /THROUGH TONIGHT/... As of 315 AM: Widespread cirrus ahead of a thunderstorm complex to our SW will continue to move over the area this morning. This has not stopped the development of low stratus across much of the area. It should also limit fog to mainly the mountain valleys where the cirrus is thinner. Can't rule out some patchy fog elsewhere though. Some stratocu will continue across the mountains where fog doesn't form. A short wave will swing across the area from the NW today, after some weak short wave energy this morning. A low pressure center will move east along the slow moving cold front moving south across the area. This, along with lingering moisture, will create scattered convection over portions of the NC mountains and I-77 corridor, with isolated convection elsewhere. Instability is expected to develop during the afternoon, especially across the CLT Metro area where MUCAPE could reach 1000 J/kg. Weaker instability is expected elsewhere. Strong bulk shear develops in the Metro area as well. The instability and shear combined with the forcing could lead to isolated severe storms with damaging wind gusts and hail the main threats. Outside of storms, gusty gradient winds are also expected. Highs will be a little above normal. The convection should taper off quickly during the evening as drier air moves in and forcing moves east. Gusts will taper off outside of the mountains but linger across portions of the higher elevations. Skies clear with some mountain valley fog possible. Lows will be around 5 degrees below normal. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... As of 302 AM EDT Friday: Expect a brief period of flattening uppper heights on Saturday, before another shortwave dives down into the Mid Atlantic Saturday night. Operational guidance depicts a swath of deep moisture associated with this feature, but it arrives slowly. Increasing cirrus from Saturday night onward...becoming overcast by late Sunday. Model profiles indicate enough subsidence to inhibit any thunder Saturday and Sunday afternoons. Temperatures will be 1-2 categories below normal on Saturday, rising to within a category of normal on Sunday. && .LONG TERM /MONDAY THROUGH THURSDAY/... As of 312 AM EDT Friday: Typical late spring pattern resumes on Monday with a wavy upper pattern. The bulk of guidance has some flavor of a deep trough or closed upper low drifting out of the Ozarks late Monday and into Tuesday, ushering in better moisture. Instability looks anemic on Monday and Tuesday, but by Wednesday, the GFS and CMC both depict a plume of afternoon CAPE intersecting a well-sheared environment. Wednesday thus looks like it could perhaps be our next severe weather day. Temps will be near or just below normal Monday, falling to at least a category below normal on Tuesday. Things will warm back up on Wednesday and beyond. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... At KCLT and elsewhere: Copious high clouds will remain over the area this morning. Some VFR stratocu will also be seen at KAVl and KHKY. IFR to LIFR stratus is developing despite the high clouds. Expect IFR to LIFR cigs for all but KHKY/KAVL, but they will be possible there as well. Any low cigs should scatter out or lift by noon. Guidance showing better chance of convection at KCLT than the rest of the sites, so have limited PROB30 to that location. W to SW wind this morning becomes gusty and more WSW for the afternoon. The gusty winds continue from the NW to N into the evening before diminishing. KAVL will see NNW wind throughout with very gusty conditions during the afternoon and evening. Outlook: Drier and likely VFR conditions can be expected this weekend. Moisture returns late Monday with active weather possible by Tuesday. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...MPR NEAR TERM...RWH SHORT TERM...MPR LONG TERM...MPR AVIATION...RWH