Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/13/19

Area Forecast Discussion
National Weather Service La Crosse WI
652 PM CDT Sun May 12 2019 .SHORT TERM...(Tonight through Monday Night) Issued at 130 PM CDT Sun May 12 2019 GOES water vapor and RAP 500mb analysis showing a closed low sinking southeastward into northern MO. Meanwhile, weak troughing/cooler air aloft was over our area with broken cumulus/stratocumulus resulting in the fairly steep lower level lapse rates. So far, radar has been quiet but a few showers through the remainder of this afternoon cannot be ruled out. Otherwise, a chilly Mother`s Day afternoon with temperatures at 1 pm ranging from the 55-60 degree mark. Look for the cumulus/stratocumulus to dissipate after sunset with high pressure building in. Lows tonight will range from the middle 30s across central WI -where some frost is possible, to the upper 30s/lower 40s elsewhere. Mid-level/surface ridge of high pressure build in for Monday for a nice beginning of the new work week. Under mostly sunny skies, plan on temperatures climbing well into the 60s. Surface high slides southeast of the area Monday night, setting up increasing warm air advection/moisture transport over the Plains into IA. All models showing a batch of showers firing in this WAA/moisture transport over the Dakotas, sliding southeast into are as west of the Mississippi River toward morning. Better CAPE will stay over the Plains, so thinking this will be a decaying area of showers/isolated storms as they approach the area. Overnight lows are expected to be in the 40s. .LONG TERM...(Tuesday through Sunday) Issued at 130 PM CDT Sun May 12 2019 Models in good agreement with a weak mid-level trough/surface cold front moving southeast through the region for Tuesday into Tuesday night, bringing in a chance of showers and isolated thunderstorms. Storms appear to be rather innocuous at this time as CAPE pool stays bottled up over the Central Plains. Otherwise, highs Tuesday look to be right around normal, peaking in 65-70 degree range. Mid-level ridge amplifies over the central CONUS/Upper Mississippi River Valley region Wednesday int Thursday for some warming temperatures. Plan on highs well into the 70s, maybe a few lower 80s for Thursday. Will have to watch for the potential of showers and storm dropping out of the Northern Plains Thursday but thinking bulk of it should stay deflected to the north of our forecast area. Friday into next weekend looks increasingly active as the ridge starts breaking down allowing deep warm/moist flow into the area along with a warm frontal boundary in the vicinity. Could see multiple rounds of shower and storms in this scenario. Otherwise, remaining warm with highs Friday/Saturday in the mid 70s/lower 80s and lower/mid 70s Sunday. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 651 PM CDT Sun May 12 2019 VFR conditions will continue through the TAF period. BKN diurnal mid-level cloud deck is already beginning to erode and will give way to mostly clear skies overnight with high pressure overhead. Light and variable winds expected through most of the period, perhaps becoming calm for awhile overnight. Despite this favorable setup for fog, there does not appear to be enough low level moisture to promote its development. Will leave it out of the TAFs and monitor trends this evening. A ridge of high pressure slides across the area Monday afternoon. This will lead to continued light winds backing from the WNW to the SW, along with a SCT to BKN stratocu deck developing again. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...DAS LONG TERM...DAS AVIATION...Kurz
Area Forecast Discussion
National Weather Service Quad Cities IA IL
621 PM CDT Sun May 12 2019 ...00Z AVIATION UPDATE... .SYNOPSIS... Issued at 258 PM CDT Sun May 12 2019 Upper level low pushing across the area was producing an area of light rain across mainly our southern cwa, where the better forcing was located. PWATs were only around 6 tenths of an inch. Rainfall amounts will generally be around a tenth of an inch or less. Cloudy skies were keeping temperatures once again well below normal for mid May, only in the upper 40s to mid 50s. && .SHORT TERM...(This Evening through Monday) ISSUED AT 258 PM CDT Sun May 12 2019 Tonight: Lingering showers in our se cwa will end early this evening. This will be followed by subsidence in the wake of the departing upper low and surface high pressure building into the area, will allow skies to clear overnight. Combined with light winds, temperatures should drop to the upper 30s at most locations. Some favored cold spots in valleys may experience patchy frost. Monday: Models suggest a sunny morning followed by increasing cu/sc in the afternoon, especially in our eastern counties. The HRRR indicates isolated showers popping in the afternoon in nw IL but confidence is low so have opted to keep the forecast dry for now. The sunshine should push afternoon temperatures into the mid 60s for a pleasant day. .LONG TERM...(Monday Night through Sunday) ISSUED AT 258 PM CDT Sun May 12 2019 Weak disturbances the first half of the week will bring a risk of some rain to the area but it should be mainly spotty and light. A change in the weather pattern points to warmer than normal temperatures developing with increasing chances for rain next weekend. Monday night Assessment...high confidence Quiet and dry conditions will be seen as high pressure moves into the Ohio Valley while an upper level disturbance approaches from the Plains. Temperatures will average below normal. Tuesday and Tuesday night Assessment...medium confidence An upper level disturbance will move through the area bringing a risk of rain. Daytime heating may allow some isolated thunderstorms to develop during the afternoon and evening. Overall moisture availability will dictate the areal coverage of any rain. Right now the model consensus has slight chance to chance pops on Tuesday with chance pops Tuesday night. Wednesday Assessment...medium to high confidence The model consensus has dry conditions for the area as high pressure builds into the western Great Lakes. Temperatures will average slightly above normal. Wednesday night on... Wednesday night Assessment...high confidence Quiet and dry conditions will be seen as high pressure moves east into the Great Lakes and Ohio Valley. Temperatures will average at or above normal. Thursday Assessment...low confidence Another upper level disturbance will move through the area in the flow aloft. The better forcing to act upon the moisture available is across Wisconsin so that raises questions on the areal coverage of any rain. Areas north of I-80 has a better chance for rain. Right now the model consensus has slight chance to chance pops for most areas north of I-80 with dry conditions south of I-80. Thursday night and Friday Assessment...low confidence Starting Thursday night and continuing into next weekend the global models diverge on their solutions in regards to the sensible weather. On the large scale all agree in developing an upper low over the Rockies with an upper level high over the southeast United States. Such a pattern places the Midwest in southwest flow aloft. Southwest flow aloft means much warmer temperatures for the area along with increasing humidity levels and thus increased chances for rain. The GFS has rain associated with the upper level disturbance that exits the area during the evening but then develops new convection along a stalled front late Thursday evening into Friday. The CMC global has no rain with the upper level disturbance exiting the area. Some isolated convection does develop across Iowa Thursday night with Friday being dry. The front remains across Minnesota and Wisconsin. The ECMWF has rain associated with the upper level disturbance exiting the area Thursday evening. Some convection develops along the front that moves into Missouri and southern Illinois. The ECMWF keeps Friday dry for the area. The FV3 has limited rain associated with the upper level disturbance exiting the area Thursday evening but has a warm front moving through the area. The FV3 has Friday mainly dry. Given the large differences between the global models, the model consensus is biased toward the GFS solution. The model consensus has slight chance to chance pops across the soutwest two thirds of the area Thursday night with dry conditions on Friday. Temperatures will average above normal. Friday night Assessment...low confidence The differences between the global models continue Friday night and the one key is where the front is located. The ECMWF has dry conditions with the front slowly moving back north as a warm front. The CMC global has the front well north of the area with only isolated convection developing. Interestingly, both the ECMWF and CMC solutions point to an atmosphere with a warm layer aloft preventing convection from developing. The FV3 keeps the front well north of the area with only limited weak nocturnal convection developing across the area. This scenario suggested a capped atmosphere as well but not to the extent of the ECMWF and CMC. The GFS moves the front back north as a warm front and develops convection along it. If one takes into account the moist bias of the GFS the overall extent of nocturnal convection would be lower. The model consensus shows this with only slight chance pops north of I-80, and, also keeps the front north of the area. The model consensus `could` be slightly underdone with the rain chances. The strength of the warm layer aloft will dictate the overall chance for rain. Saturday through Sunday Assessment...medium to high confidence on more active weather and warmer than normal temperatures. Low confidence regarding the areal coverage and timing of precipitation. Next weekend the only thing the models agree reasonably well upon is for warmer than normal temperatures. They vary considerably in regards to rain chances. The key factor in the rain potential appears to be related to the depth and position of the upper low. The ECMWF has a deep upper low over the Rockies that is slow to eject into the Plains. As a result it keeps the area mainly dry Saturday with rain moving into the area Saturday night and Sunday with the next system. The CMC global is not as deep with the upper low but does have it further west and north over the Rockies with a slower ejection into the Plains. The CMC does develop some diurnal convection Saturday afternoon but keeps the area dry Saturday night with rain moving into the area on Sunday with the next system. The GFS and FV3 are not as deep with the upper low over the Rockies. As a result both eject the next system into the Plains faster. The GFS and FV3 both develop convection during the day Saturday and then maintain it to varying degrees as the next system arrives Saturday night into Sunday. The model consensus is biased toward the GFS solution and has slight chance to chance pops Saturday with chance pops Saturday night and Sunday. && .AVIATION...(For the 00Z TAFS through 00Z Monday Evening) ISSUED AT 621 PM CDT Sun May 12 2019 Rain associated with a passing upper level low will exit the region early this evening, giving way to slowly clearing VFR level clouds. High pressure at the surface will provide light and variable winds overnight. Depending on trends with clearing skies and lingering low level moisture, there will be the potential for fog late tonight into Monday morning. Confidence in just how thick or widespread fog will be is low at this time. Thus, a period of MVFR visibilities was introduced at all sites as a middle of the road placeholder, and trends will be watched closely for later updates. Monday, conditions will be VFR once any early morning fog clears with light winds and partly cloudy skies. && .HYDROLOGY... Issued at 1140 AM CDT Sun May 12 2019 The most recent rise on the lower Rock river from heavy rain over a week ago is ending. Both Moline and Joslin are leveling out will will begin to fall soon. Minor rises will be seen on the Cedar, Iowa and Wapsipinicon rivers as heavy rain across Minnesota over a week ago continues to move downstream. On the Mississippi the river continues to fall. LD11 is now below flood stage and Camanche has fallen to minor flood stage. Heavy rain that fell over a week ago across Minnesota and Wisconsin will be working downstream this week. This additional water will create either a very minor rise or slow down the rate of fall. Looking ahead while there are some chances for rain this week it will be spotty with light amounts. Thus river levels are not expected to be impacted. Looking further ahead toward next weekend the global weather models are suggesting the weather pattern will turn more active. However the weather models disagree on potential rainfall amounts. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...Haase SHORT TERM...Haase LONG TERM...08 AVIATION...Sheets HYDROLOGY...08
Area Forecast Discussion
National Weather Service Peachtree City GA
725 PM EDT Sun May 12 2019 .UPDATE... Updated for the 00Z Aviation Discussion. && .PREV DISCUSSION... /Issued 311 PM EDT Sun May 12 2019/ SHORT TERM /Tonight through Monday Night/... MCV continues to rotate through the southern sections of the forecast area providing the focus for a line of showers and thunderstorms. A few warnings have been issued but activity is quickly translating eastward and should be out of the area within the next couple of hours. Further north, areas of North GA have been dealing with low clouds for much of the day resulting in limited instability. Only recently have we seen temps get into the 70s. This is allowing for slightly increased instability and with the forcing of the approaching frontal boundary, shower activity is increasing. Models differ on the potential for this area of showers to blossom into an actual line of convection. The HRRR develops a line once activity gets to the ATL metro late while the NSSL WRF indicates barely a line of showers. As such, will continue to just advertise mid range chance pops for now for later this afternoon along with mainly isolated thunderstorm activity. Generally clearing conditions overnight although with all the rain, could see some patchy dense fog conditions develop in the wind sheltered areas mainly. Much cooler conditions anticipated with low to mid 50s by Monday morning for the northern tier. Should be an outstanding Monday in store with cooler and drier conditions under a developing full sun. Have been in a summer type pattern for quite a while so the respite will be quite nice. Very cool though for this time of year Monday night with some mid 40s across the far NE sections. Deese LONG TERM (Tuesday through Sunday)... Dry and seasonably cool conditions will prevail Tuesday as the area continues to be influenced by deep long-wave trough over the eastern half of the CONUS. An embedded disturbance will drop southeast and affect parts of the area as early as Wednesday (12z GFS and ECMWF are a bit slower than NAM). Regardless of timing, moisture is rather limited so do not expect any widespread/significant precip with this system. Upr ridge begins to build from the west toward the end of the work week which will allow temps to warm back up above normal for this time of year. A deeper upr trough / storm system will approach the central and northern High Plains by the weekend, which will likely enhance the upr ridge over the Southeast. No definitive features to support any organized convection at this time. DJN.83 && .AVIATION... 00Z Update... Two bands of showers still progression across the forecast area. They are diminishing and will go with VCSH at all sites for the first few hours this evening. Cigs will remain VFR this evening however expect MVFR cigs to develop, mainly across ATL/AHN late tonight. All cigs will become VFR by mid to late morning Monday and remain VFR. Winds will be northwest through the forecast, becoming gusty Monday afternoon. //ATL Confidence...00Z Update... Medium on MVFR cigs late tonight. High on the rest of the forecast. 17 && .PRELIMINARY POINT TEMPS/POPS... Athens 59 76 51 74 / 60 5 0 0 Atlanta 59 75 52 73 / 30 5 0 0 Blairsville 52 67 44 67 / 20 10 0 0 Cartersville 56 74 49 72 / 20 5 5 0 Columbus 62 80 55 77 / 30 5 0 0 Gainesville 57 73 50 72 / 30 5 0 0 Macon 62 80 53 78 / 60 10 0 0 Rome 55 74 48 73 / 20 5 5 0 Peachtree City 58 76 51 74 / 40 5 0 0 Vidalia 68 83 58 80 / 40 20 5 0 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...17 LONG TERM....Thiem AVIATION...17
Area Forecast Discussion
National Weather Service Indianapolis IN
1133 PM EDT Sun May 12 2019 .UPDATE... The AVIATION section has been updated below. && .SYNOPSIS... Issued at 212 PM EDT Sun May 12 2019 An upper level low pressure system will pass through the Region tonight. This will result in more and wet weather overnight and on Monday morning. High pressure will then build across Indiana and the Ohio Valley on Monday afternoon...passing across the state through Tuesday. This will bring dry weather...along with warming temperatures each day. Rain chances will return on Wednesday as another area of low pressure arrives in the Ohio Valley. Chances for rain will persist on Wednesday through the end of the work week. && .NEAR TERM /Rest of Tonight/... Issued at 942 PM EDT Sun May 12 2019 Forecast is in pretty good shape. An upper low will bring rain mainly to the northern forecast area tonight. Tweaked hourly PoPs to match current conditions and latest hi-res model data, but overall trends remain the same. Made some minor adjustments to temperatures but no significant changes made. Previous discussion follows... Surface analysis early this afternoon shows low pressure in place across West Virginia...providing broad cyclonic flow across the region. Cool NE surface flow was in place across Indiana. Meanwhile aloft a weak upper level weather disturbance will pushing some scattered showers across Indiana. Water Vapor Imagery shows an upper low over Iowa and Missouri. Models tonight show the upper level low to the west will progress across Indiana tonight. Lower level moisture remains plentiful as this feature seen within the time height sections and the forecast soundings. Time heights show weak forcing aloft as the upper low passes. HRRR suggests a wave of light showers passing across the forecast area...particularly focused across the northern half of the forecast area. Furthermore...abundant lower level moisture and weak forcing should also be able to produce some drizzle. Thus will trend toward light rain and drizzle...with best chances across the northern parts of the forecast area late tonight. Given the expected clouds and rain chances will trend lows at or above the forecast builder lows. && .SHORT TERM /Monday through Wednesday/... Issued at 212 PM EDT Sun May 12 2019 GFS and NAM show the upper low exiting the region on Monday afternoon as NW flow begins to develop aloft. Forecast soundings show lower level clouds lingering for much of the day before stronger subsidence arrives near 00Z. Thus much of the day looks to be clouds...with decreasing clouds in the last afternoon as subsidence builds. Will limit any precip chances to the morning hours associated with the departing upper low. Ridging aloft over the western plains is set to develop on Monday night into Tuesday...resulting in lee side subsidence and high pressure building across Indiana and the Ohio valley on Tuesday. Forecast soundings on Tuesday into Wednesday go dry. Thus will trend toward a dry forecast on Tuesday and Tuesday night. By wednesday the surface high is expected to drift east of Indiana as warmer and more humid southerly flow develops on the backside of the high. meanwhile aloft within the NW flow a short wave is suggested to approach. Forecast soundings respond showing good lower level moisture through the day. Thus will include pops on Wednesday as these features approach. && .LONG TERM /Wednesday Night through Sunday/... Issued at 303 PM EDT Sun May 12 2019 The broad upper trough that will keep cooler conditions across much of the eastern U S for the first half of the week will lift out during the latter part of the work week and eventually be replaced by a strong ridge as an upper low sets up over the Rockies then shifts into the High Plains over the weekend. The result will be a transition back to much warmer temperatures over the Ohio Valley by the weekend with 80s anticipated for highs Friday through Sunday over much of the area. Much drier conditions are expected throughout the extended with just a few threats for scattered convection. The first will come late Thursday into Friday as a frontal boundary slides into the region then lifts north as a warm front...with the second coming during the tail end of next weekend as low pressure tracks into the western Great Lakes. && .AVIATION (Discussion for the 130600Z TAF Issuance)... Issued at 1133 PM EDT Sun May 12 2019 Poor conditions expected overnight, then improvement to VFR during the daylight hours of Monday. An upper low will continue to bring low clouds and patchy light rain/drizzle to the area overnight. Not expecting much in the way of visibility restriction, but MVFR/IFR ceilings will prevail. Lowest ceilings are expected to be at KIND/KBMG, and these may vary at times between IFR and MVFR. After the low passes to the east Monday, a gradual improvement to VFR is expected from west to east during the day. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...Puma NEAR TERM...Puma/50 SHORT TERM...Puma LONG TERM....Ryan AVIATION...50
Area Forecast Discussion
National Weather Service Memphis TN
1100 PM CDT Sun May 12 2019 .UPDATE... Updated to increase rain chances in the short term and add thunder. && .DISCUSSION... HRRR not painting the proper picture with convection this evening. The line has been able to sustain itself...producing wind gusts of 27-32kts and rainfall amounts near a half inch. Have updated the late evening forecast to account for increased rain chances along the Mississippi River and added a slight chance for a few cracks of thunder. Then kept a slight chance for showers over a majority of the eastern counties during the overnight hours. JAB && .PREV DISCUSSION... /issued 626 PM CDT Sun May 12 2019/ UPDATE...Aviation Discussion. PREV DISCUSSION... /issued 300 PM CDT Sun May 12 2019/ A cool Spring day is underway across the Mid-South. Temperatures are generally in the low to upper 60s across the entire area under mostly cloudy skies. Latest surface analysis places a cold front from Cape Girardeau, Missouri, southwest through Jonesboro, Arkansas and back through the ArkLaTex region. The front will continue to push through the Mid-South through this evening. Simultaneously, a longwave trough will pivot across the northern half of the forecast area through tomorrow morning. With limited moisture in place, only light and scattered showers are expected through midnight across the area. Thereafter, skies will clear out and temperatures will fall into the lower 50s areawide. A few places near the Tennessee River may even drop into the upper 40s. Monday through Friday... A pretty good stretch of weather is in store for the Mid-South through this period. Surface high pressure will build into the region on Monday. Sunny skies will return and temperatures will warm into the upper 60s to lowers 70s. Tuesday will be nearly identical with slightly warmer temperatures during the day. High pressure will slide east by Tuesday night and winds will turn back around to the south. Synoptic models are consistent with a frontal boundary moving into the Mid-South late Tuesday night into Wednesday and spawning showers across the north. This front is expected to stall somewhere near the I-40 corridor during the day on Wednesday. With a humid airmass in place, good chances for diurnally driven showers and thunderstorms are possible. For now, kept about 30-40 POPs as models differ on coverage at this point. By Thursday, the upper level ridge will build in across the area and keep the Mid- South effectively capped through Saturday. Expect highs in the low to mid 80s and increasing humidity through next weekend. The models differ on timing of the next system, but showers and thunderstorms are a good bet by late Sunday at this point. AC3 && .AVIATION...00Z TAFs There are a few showers approaching JBR, but coverage should diminish over the next few hours. VFR conditions should prevail at all sites for the next 24-30 hours. Winds North to Northwest 3-6kt. 30 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
1007 PM EDT Sun May 12 2019 .SYNOPSIS... A cold front will slowly approach from the northwest tonight and push offshore Monday. Cool high pressure will build in from the west through midweek. A cold front with limited moisture will cross the area late week. High pressure will build over the area next weekend. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... As of 955 PM Sun...Dry across the region with regional rdrs showing band of shra/tsra well to the NW. High res mdls and quick look at 00z NAM show mainly dry weather rest of the night. Lowered pops to slight chc most areas with low chc nrn tier late with front approaching. With continued SSW flow, overnight lows will continue mild in the mid to upper 60s inland and around 70 beaches. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... As of 335 PM Sun...Though deepest moisture will be displaced by drier westerly flow, the combination of a strong mid level trough and surface cold front moving through the area should trigger scattered showers and thunderstorms mainly in the afternoon. The guidance is forecasting a persistent area of low clouds through the morning limiting heating/destabilization but if some insolation develops ahead of the front, a few of the storms could be strong with gusty winds. Highs will be in the upper 70s to lower 80s. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... As of 3 PM Sunday...Dry and much cooler weather expected through mid week, then generally dry with a building heatwave expected by late week and into next weekend. Monday night through Thursday...Cyclonic flow aloft continues through mid week with an upper low tracking from New England to the Canadian Maritimes and several embedded shortwaves moving through the flow aloft. By Mon evening, the cold front will be offshore with low pressure lifting off the New England coast. Could see lingering showers, mainly across eastern sections, in the evening, then cool and dry air filters in through the overnight. Lows will drop back to below climo for a change, in the low/mid 50s interior, with upper 50s along the beaches. Surface high pressure builds in from west through Wed, then slides offshore Wed night and Thu. Mainly dry weather is expected through Wed with comfortable dewpoints in the 40s. Temps will be several degrees below climo with highs around 70-75 inland to upper 60s OBX. Lows expected in the mid to upper 40s inland to mid 50s along the coast. A shortwave through digs southeastward on lee side of longwave Wed night and Thu, trough has limited moisture to work. A few of the 12z models show light QPF, so cannot rule out a few showers, but if anything develops will be very widely scattered. A moderating trend in temps expected as flow begins to become zonal with sfc high offshore. Temps expected to rise to near climo, with lows in the low to mid 50s Wed night. High Thu expected in the upper 70s to lower 80s interior to the mid 70s beaches. Lows Thu night mid/upr 50s inland to low 60s beaches. Friday through Sunday...High pressure and upper ridging is progged to build in late in the week and over the weekend bringing generally dry weather and warming temps and could see highs approach 90s over the weekend. However, the 12z operational GFS and EC now show a final shortwave and backdoor cold front crossing the area Friday night into early Saturday with a few light showers pushing across the area, but will wait to see if this trend continues in the models before buying into this solution. These models also flatten the upper ridge as it migrates from the Mississippi River Valley to the eastern CONUS with not quite as warm temps across the region. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... Short Term /through Monday/... As of 645 PM Sun...Mainly VFR thru evening with brief lowering in wdly sct to sct convection. Cigs expected to grad lower to MVFR/IFR late tonight and early Mon morn. Ceilings will improve Mon afternoon with scattered showers and thunderstorms possible ahead of a cold front moving through the area. Long Term /Monday night through Friday/... As of 345 PM Sunday...Any lingering showers across the region will push offshore Monday evening with pred VFR conditions across rtes. High pressure builds into the area through the rest of the week with pred VFR conditions expected. && .MARINE... Short Term /through Monday/... As of 955 PM Sun...Earlier convection disrupted the gusty SSW winds along the cst. HRRR and 00Z NAM keep winds over nrn tier and Pamlico Sound below 25 kts so have dropped SCA Sounds and nrn wtrs. Winds will likely remain gusty off the central and srn wtrs with some 6 foot seas poss. Prev disc...SCA`s are in effect for all of the coastal waters and Sounds. Latest obs show SW winds 20-25 kt with gusts to 30 kt this afternoon and seas 3-5 ft. Deteriorating conditions through this evening as gusty southerly winds produce seas of 4 to 7 ft. Gusty SW winds will continue into Mon morning with winds becoming westerly 15-20 kt south of Oregon Inlet/Pamlico Sound. Winds will become N/NW towards evening as a cold front crosses the waters late. Seas will continue 4-6 ft south of Oregon Inlet through the day. Long Term /Monday night through Friday/... As of 4 PM Sun...High pressure builds into the are through mid week. N/NW winds around 15-20 kt Mon evening diminishes to NW around 10-15 kt overnight into Tuesday. Seas around 3-5 ft and up to 6 ft across the central northern waters Mon evening, subsides to 2-5 ft Tue. The upper level trough axis crosses the area late Tue/Tue night which will serve to tighten the gradients across the waters with NW winds increasing to 15-20 kt with higher gusts. Gradients quickly weaken Wed with winds diminishing from 10-20 kt early to less than 10 kt and seas subsiding to 2-4 ft northern waters and 1-3 ft southern waters in the afternoon as high pressure builds across the area. The high becomes centered offshore Thu and Fri with SW to W winds around 15 kt or less with seas around 2-4 ft. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...Small Craft Advisory until 2 AM EDT Tuesday for AMZ152-154. Small Craft Advisory until 9 PM EDT Monday for AMZ156-158. && $$ SYNOPSIS...MHX NEAR TERM...RF SHORT TERM...JME LONG TERM...SK AVIATION...RF/SK MARINE...RF/JME/SK
Area Forecast Discussion
National Weather Service Marquette MI
734 PM EDT Sun May 12 2019 .SHORT TERM...(This evening through Monday) Issued at 312 PM EDT SUN MAY 12 2019 WV imagery and RAP analysis indicated mid/upper level troughing from Hudson Bay into the central CONUS where a closed low was circulating near the mid-Mississippi Valley. Weak forcing ahead of a shortwave lobe extending through this trough into northern MN and the central Plains was helping to support instability cu and some isolated showers into far western Upper Mi today. At the surface, high pressure extending from northern Quebec into the northern Great Lakes has resulted in light winds and mostly sunny skies across much of the rest of Upper Michigan with the exception of an area of cumulus clouds over the eastern counties. Afternoon temps have generally been in the 50s with a few lower 60s readings. Tonight, after instability cu dissipates this evening, favorable radiational cooling should allow min temps to drop into mid to upper 20s over some the favored interior central cool spots and into generally the lower to mid 30s elsewhere. Monday, the mid-level trough axis shifts east and will be replaced by rising 5h heights from the west. Still expect some diurnal cu to form but dry conditions will prevail. With sfc high pressure in place, expect lake breezes to prevail, but it likely won`t be until late in day that the lake breeze develops off Lake MI. Away from lake moderation, temps will reach the mid and upper 60s. .LONG TERM...(Monday night through Sunday) Issued at 231 PM EDT SUN MAY 12 2019 Well, WFO Marquette is currently on its longest streak of days (236) with high temperatures remaining below 70 degrees. As the forecast stands now, Tuesday is our next best shot at reaching the 70 degree mark, with temperatures expected to reach the mid to upper 60s. Cloud coverage and timing with expected cold front will be a key factor. Steady SW winds will help combat any type of Lake Superior breeze that tries to form, though areas north of Lake Michigan may not appreciate that as temperatures will be suppressed down in the 50s. The last time the office has seen temperatures above 70 degrees was back on Sept. 17th, when we reached 80 degrees. Normal temperatures at this point in May are now into the low 60s; May so far has been about 10 degrees below normal. Looking deeper into this Tuesday, a surface low will pass to the north through NW Ontario and into Hudson Bay as an associated trough and cold front pass across Lake Superior and Upper Michigan. Depending on the model, rain showers will begin across western UP in the afternoon or evening, with the GEM beginning closer to mid day and GFS sometime after dinner. Stay tuned to future forecasts for a clearer picture. A rumble or two is possible with a few hundred J/kg showing up on convective based models; however, 60 hours out on convective-allowing models can often introduce more moisture and instability than what will actually occur. Overall, QPF ranges from 0.10-0.25 inches, highest amounts with the NAM. After the fropa, some clearing is expected Wednesday as high pressure builds in, though not expecting much of a cool down from cold front except for temperatures near Lake Superior with usual N to NW flow behind front. The next chance for precipitation comes later Wed night into Thurs morning as a shortwave approaches from the Canadian Prairies. The ECMWF comes in much slower bringing precip into the UP Thur night into Fri morning. QPF values look similar to the precip on Tuesday night. As the weekend comes closer, a large area of surface high pressure develops in the Canadian Arctic stretching an extensive ridge S to SE towards Upper Michigan. The forecast becomes a bit tricky here as global models come to an agreement on the high pressure across northern Canada, but it still remains unclear on how this will affect an approaching low pressure from the Central Plains. Current model forecasts show this high pressure serving as a blocking mechanism for the approaching low pressure and associated precipitation, keeping most precipitation to the south and west on Saturday. On Sunday, 12Z GFS shows a low pressure system crossing Upper Michigan bringing widespread rain throughout the CWA with some areas forecast to exceed the 1 inch mark. The ECMWF and GEM track further to the west, but bring similar QPF values expected across the Northland and Arrowhead in Minnesota. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 732 PM EDT SUN MAY 12 2019 The benign weather conditions for aviation interests will continue through this TAF period at all three terminals. VFR conditions will prevail with light to calm winds, especially overnight, and a diurnally-driven CU field tomorrow. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 312 PM EDT SUN MAY 12 2019 Winds will generally be 20 knots or less into much of next week as surface high pressure dominates into Tuesday and then a couple of weak cold fronts move through mid to late week. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...Voss LONG TERM...JAW AVIATION...lg MARINE...Voss
Update to aviation forecast discussion.

&& .SHORT TERM...(THIS EVENING THROUGH Tuesday NIGHT) ISSUED AT 201 PM CDT SUN MAY 12 2019 Upper level low over northern Missouri is forecast to slide east and open up overnight tonight. Scattered showers and thunderstorms were on-going at this time near the low. HRRR output suggests scattered to isolated showers and thunderstorms are possible over SEMO and parts of southern Illinois and Indiana until shortly after midnight tonight. Freezing levels of 6-8K ft would suggest small hail is possible in the stronger showers/storms. Surface high pressure should control our weather through Tuesday with cool nights and increasingly warm days. During the day Tuesday and into Tuesday Night an upper level ridge builds over the central part of the country. A piece of energy caught in northwest flow will slide down into our area Tuesday Night. This will bring a chance of showers and possibly a few thunderstorms during that time. Mainly elevated thunderstorms with decent K indices and little surface based CAPE. .LONG TERM...(Wednesday THROUGH Sunday) ISSUED AT 201 PM CDT SUN MAY 12 2019 The primary forecast concern in the long term is the potential for showers and thunderstorms on Wednesday, then again by the latter half of next weekend. Forecast confidence through much of the long term is higher than average, but decreases with greater model variability next weekend. Showers and some elevated thunder will likely be scattered across the area Wednesday morning as a weak disturbance streams through the northwesterly flow pattern. Previous thinking was that energy from the disturbance may time out with peak afternoon heating to refire scattered thunderstorms across the area Wednesday afternoon and evening. However, the latest guidance seems to suggest that the best chance for showers and thunderstorms may occur Wednesday morning, with chances lowering and/or moving largely south of the region by afternoon and evening tied to remnant MCV and boundary interactions from the morning convection. Will still carry small chances during the afternoon and evening, especially across the southern half, in case anything were to fire. The forecast from Thursday through Saturday is largely dry and much warmer as an upper level ridge over the Plains builds east into the Mississippi, Ohio, and Tennessee River Valleys through Saturday. While a mid level capping inversion should tend to limit convective updrafts, it`s not out of the realm of possibility that an isolated shower or thunderstorms could develop, especially along the leading edge of the incoming warm sector Thursday afternoon. The ECMWF and CMC are markedly stronger than the GFS with the ridge by the weekend, with the ensemble means supporting each operational model`s depiction. As a result, the GFS is also faster to bring the potential for showers and thunderstorms back into the region by Saturday night and Sunday as energy associated with an upper level trough over the Plains approaches. The model blended forecast will carry at least a small chance for showers and thunderstorms late Saturday night and Sunday. As the upper level ridge builds east, expect a warming trend through late week. Highs in the upper 70s on Wednesday should warm well into the 80s through late week. Likewise, lows in the upper 50s Wednesday night should slowly moderate into and through the 60s heading into the weekend. && .AVIATION...(FOR THE 00 TAFS THROUGH 00Z Tuesday) ISSUED AT 737 PM CDT SUN MAY 12 2019 Mainly VFR conditions at KCGI/KPAH with MVFR/IFR at KMVN/KEVV/KOWB. Light showers or drizzle impacting KEVV/KOWB will move east over the next few hours. Other showers are inbound that might affect KCGI, KMVN and KPAH this evening. Plenty of low level moisture around for the next 24 hours but the problem will be figuring out cloud heights. Expecting conditions to be VFR later tonight at our eastern sites that are now MVFR. As we head toward morning though, there is some suggestion that we could go back down. Played the forecast fairly optimistic but did linger VFR cigs through a good chunk of the day tomorrow. We will re- evaluate cigs again at the 06Z fcst. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$
Area Forecast Discussion
National Weather Service Blacksburg VA
1135 PM EDT Sun May 12 2019 .SYNOPSIS... A weak cold front will cross the region from the west tonight followed by a stronger secondary cold front early Monday. This will result in continued rounds of showers and storms into tonight along with added showers on Monday as an upper level area of low pressure slides across the area. Cool high pressure will follow bringing cool temperatures on gusty northwest winds by Monday afternoon into Tuesday. && .NEAR TERM /THROUGH MONDAY/... As of 1133 PM EDT Sunday...Stationary front/wedge boundary extends roughly as far south as the Roanoke River per wind shift in regional METARs with radar showing scattered showers across central VA into Southside. A few of which have some in-cloud lightning associated with them, though lightning trends have been downward and should continue to do so. Weakening of this activity is highly probable as this shifts eastward into eastern Virginia over the next hour to 90 minutes. Though light west-northwesterlies generally prevail across the foothills and westward, aloft the region is still in a southwest flow and this will help keep clouds around and the threat of isolated to scattered showers going into the overnight. We`re still several more hrs away - at least not till sunrise - until the primary upper level trough begins to intrude into our forecast area. A re-blossoming of showers then should occur by daybreak as a shortwave trough rounding the base of the upper trough - this feature seen in WV imagery over southern Illinois - pivots into our area. Opted to raise temperatures and lows up some 2-4 degrees given delayed onset of sharper cooling and at least mostly cloudy skies. Previous discussion from this afternoon... Low pressure in northern West Virginia and western Pennsylvania has push the warm front a little north this afternoon. Meanwhile Surface cold front is just to the west of the mountains. The cold front will travel east tonight into Monday. Scattered showers and thunderstorms will develop across our area this afternoon into tonight. Extensive cloud cover and a westerly wind has hindered convection. However, the combination of isentropic lift, deep moist southwest wind flow, dynamic forcing from shortwave aloft and orographic lift will create showers and thunderstorms. This morning 12z RNK sounding showed a healthy PWAT at 1.46 inches. PWATs within this airmass with a deep southwest flow are more indicative of mid-summer. Deep convection this afternoon can be rain efficient with locally heavy rains. However, the moderately sheared environment will caused the heavier convection to be transient. Because of the movement of storms and spring greening will hold off on any flash flood watch. FFG is relatively high and coverage scattered. SPC Convective Day One outlook has pushed the marginal risk for severe weather a little farther south. Now, it highlights southern and eastern portions of our forecast area with a marginal risk. SPC Mesoscale Analysis at 18z showed SBCAPE has risen to 1000 to 1500 east of the Blue ridge. The supercell composite parameter paint the best chance of severe to our east across eastern Virginia and eastern North Carolina. It still looks like some of the storms this afternoon into tonight could be strong to severe. In a moderately sheared environment, with storm relative 0-3km helicity in the 150 to 200 range, conditions do support rotation for thunderstorms that gain any depth aloft, and especially so if they are co-located along a boundary. For this afternoon into tonight shaped pops towards a blend of the HRRR and NAM. Most solution indicated the best chances across southern portions of the forecast area. Low temperatures tonight will range from the mid 40s in the northwest mountains of Greenbrier county in West Virginia to near 60 degrees in the piedmont. Upper low will move east through the southern Great Lakes Monday into Monday night. This will keep a persistent flow of cool air and low level moisture on strengthening northwest flow. The result will be upslope clouds and showers persisting in the west. While in the east, a gradual improvement is expected with downsloping flow. A gusty northwest wind Monday afternoon should remain below wind advisory levels. High temperatures on Monday will vary from the upper 40s across the north to the lower 70s in the piedmont. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... As of 255 PM EDT Sunday... Strong cool advection will continue Monday night into Tuesday morning as an upper low passes north allowing surface low pressure to deepen off New England. Pressure gradient between this feature and high pressure to the west should keep gusty northwest winds in place as 850 mb temperatures also cool to near 0 deg/C over the mountains by early Tuesday. This trajectory looks to dry out eastern sections per downsloping Monday night, while low level moisture combined with the cool advection and northwest flow likely to keep some upslope showers going northwest ridges into Tuesday. Lows Monday night mainly 40s with a few 30s deeper valleys, but overall not as cool as guidance due to continued mixing. Moisture will decrease further Tuesday as high pressure builds in although likely Tuesday night before the pressure gradient decreases. This along with cold air aloft should make for a very cool/blustery day for mid May on Tuesday with highs only 50s/60s despite increasing sunshine. High pressure finally builds overhead Tuesday night into Wednesday with dry air making for a very cool overnight before slowly modifying during the day as warming aloft ensues. Appears great radiational cooling to allow temperatures to bottom out by Wednesday morning with lows well into the 30s in the deeper valleys, with upper 30s to mid 40s elsewhere. This may be enough to support some patchy frost in the coldest locations but likely quite spotty at best and only in the mountain valleys if at all given the warm ground/wetness. Highs Wednesday rebounding through the 60s to near 70 mountains and low/mid 70s east. Airmass should modify enough despite clear skies to see lows stay a bit warmer Wednesday night, but still 40s to low 50s, with isolated 30s in the deepest valleys again overnight. && .LONG TERM /THURSDAY THROUGH SUNDAY/... As of 100 PM EDT Sunday... Lingering northwest flow aloft will continue to start the period followed by a transition to mid level ridging and much warmer weather for next weekend. This scenario should result in passage of another weak surface cold front Thursday before seeing high pressure offshore start to dominate under the southeast ridging above. Moisture again limited within the northwest flow with the front, so appears only a few showers possible mainly mountains on Thursday. Airmass will then dry out Friday into Saturday as subsidence increases before dewpoints start to rebound by Day7 under return flow aloft. This looks to also tap into much warmer air to the west that should advect east as the flow aloft turns more westerly under the developing ridge. Return moisture combined with strong heating by Sunday may be enough to pop more orographic summer-like convection over the ridges where will carry isolated thunder mountains Saturday, and chance pops Sunday afternoon. This per the drier ECMWF/CMC vs. the wetter GFS that has weaker ridging aloft through the weekend. Otherwise after a cool start to Thursday, will see a steady increase in temperatures through the weekend as heights rise and 850 mb warming kicks in. Could even be close to 90 east of the Blue Ridge by the end of the weekend, but not much humidity until the very end of the period. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... As of 800 PM EDT Sunday... Main line of showers and thunderstorms is currently passing east across KDAN, and will exit the area to the east by 13/02Z, leaving lingering shower activity across the area through the early morning hours of Monday. Models hinting at high pressure over the DelMarVA nudging southward across the area overnight, shifting winds east northeasterly and bringing ceilings in the MVFR/IFR range, though not entirely confident how far the cold front/leading edge of this weak high pressure will make it into the area. After daybreak Monday, a stronger cold front will pass east across the central Appalachians, resulting in a westerly wind shift areawide. May see an additional round of showers and possibly thunderstorms develop just ahead of the front, primarily affecting KDAN and an outside chance at KLYH. Downsloping associated with the westerly flow will allow ceilings to improve from east to west, with VFR conditions returning to much of the area during late morning to early afternoon. Gusts behind frontal passage will increase into the 20 to 25kt range during the afternoon. Confidence in the above portion of the aviation forecast is moderate. EXTENDED AVIATION DISCUSSION... A few MVFR showers will continue in the western mountains Monday evening. Then, they will taper off Monday night. Tuesday will be VFR under high pressure. Isolated to scattered MVFR showers are possible on Wednesday in the west. Drier air will come in for Thursday. Medium to High confidence in the extended portion of this forecast. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...JH NEAR TERM...AL/KK SHORT TERM...JH LONG TERM...JH AVIATION...KK/NF