Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/15/19

Area Forecast Discussion
National Weather Service La Crosse WI
949 PM CDT Sat Sep 14 2019 .SHORT TERM...(This evening through Sunday) Issued at 245 PM CDT Sat Sep 14 2019 At 2 PM, skies were partly to mostly cloudy across the Upper Mississippi River Valley. Scattered showers and isolated storms have developed along and north of the Interstate 90 corridor. The most robust convection was north of the Twin Cities. This latter precipitation is located on the nose of the 850 mb jet. This jet is bringing an increase in the moisture and instability ahead of a shortwave trough over northwest Minnesota. Additional storms were located across central Iowa. This is associated with a MCV that developed overnight in eastern Nebraska. This convection with this system will likely remain south of the area. Temperatures were in the mid and upper 60s north of Interstate 94 and in the 70s elsewhere. For this evening, the 14.12z models are in good agreement that the nose of the 850 mb jet will move into the Upper Mississippi Valley. As this occurs, the 0-1km ML CAPES will climb up into 1500 to 2500 J/kg. Soundings continue to suggest that any showers and storms will be elevated. The 1-7 km shear is very marginal for the potential development of elevated supercells. The main threat would be gusty winds and hail. With precipitable water values between 1.3 and 1.8 inches, these storms will be efficient rain producers. The CAMs are really struggling with the development and the placement of showers and storms this afternoon, so confidence is not extremely high on how this is exactly going to play out this evening. Overall, the experimental ESRL HRRR seems to be handling the precipitation the best at the this time, so trended the PoPs toward it. It would suggest the current convection north of I-94 would move east across Clark and Taylor counties early this evening. Additional convection would then develop along and south of the Interstate 90 corridor during the mid to late evening. For overnight, the nose of the 850 mb jet will veer and move east of the area. As this occurs, expect the showers and storms to progressively move south and east out of our area. With this area being so wet, it would not take much rainfall to cause additional flooding, so kept the Flash Flood going. Low temperatures tonight will range from the mid 50s to mid 60s. On Sunday, high pressure will gradually build across the region. Skies will gradually clear from the west. High temperatures will range from the mid 70s to mid 80s. .LONG TERM...(Sunday night through Saturday) Issued at 245 PM CDT Sat Sep 14 2019 From Monday into Tuesday night, temperatures look to be well above normal. 850 mb temperatures are running 1 to 2 standard deviations above normal. Due to this, went a couple of degrees above the MOS. From Tuesday into Wednesday, there continues to a lot of uncertainty on the eastern extent of a mesoscale convective complex. The GFS would move it through our area. The ECMWF would move it northwest of our area from Tuesday night into Wednesday. Meanwhile, the Canadian keeps much of its precipitation north of Interstate 90. Due to these uncertainties, made little change to the NBM precipitation chances. && .AVIATION...(For the 06Z TAFS through 06Z Sunday night) Issued at 949 PM CDT Sat Sep 14 2019 Main aviation concerns are on scattered showers and storms tonight and MVFR to IFR stratus late tonight into Sunday morning. Scattered showers and storms will move across the area tonight with most of this activity staying south of the TAF sites. Then guidance is suggesting low stratus develops across the area mainly after 09Z. Ceilings are expected to fall to around 600 ft at KRST by 11Z and to around 1500 ft at KLSE around 11Z. High pressure then builds into the area late Sunday morning into Sunday afternoon with a return to VFR conditions. && .HYDROLOGY...Tonight Issued at 354 PM CDT Sat Sep 14 2019 Moderate to strong 850 mb moisture convergence will move into the area this evening and then move quickly out of the area between 15.09z and 15.12z. With preciptable water values of 1.3 to 1.8 inches, these storms will be capable of producing heavy rain. Rainfall amounts will range from a half to 1 inch, but repeat thunderstorms over localized areas could produce higher amounts. With the recent rainfall, soils are saturated, and creeks and rivers are already running higher than normal. This means it will take less rainfall to cause mudslides and flooding. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...Flash Flood Watch until 7 AM CDT Sunday for WIZ053>055-061. MN...Flash Flood Watch until 7 AM CDT Sunday for MNZ086-087-094>096. IA...Flash Flood Watch until 7 AM CDT Sunday for IAZ008>011-018-019- 029-030. && $$ SHORT TERM...Boyne LONG TERM...Boyne AVIATION...Wetenkamp HYDROLOGY...Boyne
Area Forecast Discussion
National Weather Service Birmingham AL
613 PM CDT Sat Sep 14 2019 .UPDATE... For 00Z Aviation. && .SHORT TERM... /Updated at 0145 PM CDT Sat Sep 14 2019/ Thus far, temperatures have remained a little more tame as compared to yesterday. (We ended up breaking record highs at all four climate sites as a result.) Wouldn`t expect to approach the century mark again today as subsidence & dry air isn`t as prevalent, though will be quite warm regardless with a run for low to mid 90s currently ongoing. Our RADAR & satellite trends have suggested that cumulus fields are showing a little more coverage/vertical growth with further development expected in the coming hours. Expecting the greatest activity along the I-20/59 corridors, & into the northeast, where best PWs are available (~1.8" as suggested by latest RAP mesoanalysis) as well as proximity to a confluent axis noted in the 850-700 mb layer. Evaluation of the 12 Z RAOB earlier this morning did suggest that a few thunderstorms could produce localized gusty winds, though the overall microburst threat remains below a confidence threshold such that mention in the HWO was not needed. Nonetheless, this update yielded PoPs generally similar to the previous forecast cycle with only minor tweaks made to account for trends in the latest HREF means. Have maintained chance PoPs in a northeast to southwest fashion through the I-20/59 corridors, with a gradual decrease in coverage & intensity towards 9 PM as activity moves southwestward. Outside of any rainfall through this evening, & a stray shower or thunderstorm tomorrow afternoon, rain chances look very low through the next several days as the synoptic pattern suggests deep-layer ridging & above average temperatures to unfortunately continue. 40/Sizemore .LONG TERM... /Updated at 0401 AM CDT Sat Sep 14 2019/ Sunday through Friday. With Tropical Storm Humberto located to the east of Florida on Sunday, Alabama will be on the drier side of the storm. However, a stray shower or storm cannot be ruled out as a narrow axis of enhanced moisture lingers along and south of I-59. Drier air will wrap around the west side of Humberto on Monday and Tuesday as subsidence increases across the region. Temperatures should soar back toward the 100 degree mark with the forecast area in the grips of an intensifying drought. Some relief may start to show up across our eastern counties on Wednesday with models indicating a wedge of high pressure along and east of the Appalachians. After one last day of upper 90s in our western counties on Wednesday, afternoon highs for Thursday and Friday should be several degrees lower. Unfortunately, there is still no rain in sight for the extended part of the forecast. 87/Grantham && .AVIATION... 00Z TAF Discussion. Isold showers and tstms will continue across central Alabama thru 02z, possibly impacting KTCL and KMGM. VFR conds will prevail thru the period with no cig or vsby issues outside convective areas. Thunderstorm chances less than 20 percent Sunday afternoon, and did not include any diurnal storms beyond 18z. 58/rose && .FIRE WEATHER... Isolated to scattered showers and storms remain possible through this evening before drier conditions return to Central Alabama. Best rain chances through tonight will be across the north. Afternoon RH values remain above 40 percent Sunday. Lower humidity and hotter conditions should return for Monday and Tuesday. KBDI values will remain elevated due to ongoing drought conditions. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 68 94 65 97 66 / 30 10 0 0 0 Anniston 69 95 67 97 67 / 20 10 0 0 0 Birmingham 72 95 70 97 70 / 30 10 0 0 0 Tuscaloosa 73 95 70 97 70 / 30 10 0 0 0 Calera 71 95 68 97 68 / 20 10 0 0 0 Auburn 70 92 70 94 68 / 10 10 0 0 0 Montgomery 71 95 71 97 69 / 10 10 0 0 0 Troy 70 94 70 96 68 / 10 10 0 10 0 && .BMX WATCHES/WARNINGS/ADVISORIES/... None. && $$
Area Forecast Discussion
National Weather Service Quad Cities IA IL
621 PM CDT Sat Sep 14 2019 .UPDATE... Issued at 614 PM CDT Sat Sep 14 2019 All our focus will be on the onset of the storms from central Iowa later this evening in the west/northwest. On the latest RAP data on SPC`s mesopage, we still see a cut off MUCAPE to nil over eastern Iowa, thus, despite the storms close proximity to eastern Iowa, I don`t expect a rapid intensification, nor widespread development of storms into our area quite yet. Later tonight, the storms should expand into an MCS with heavy rain over our area, which still in somewhat in question on how far north or south this tracks. && .SYNOPSIS... Issued at 312 PM CDT Sat Sep 14 2019 18Z surface data has a weak warm front running from eastern Iowa back into the eastern Dakotas. Dew points were in the 50s across the Great Lakes with 60s and 70s from the Mississippi Valley into the Plains. && .SHORT TERM...(This Evening through Sunday) ISSUED AT 312 PM CDT Sat Sep 14 2019 Headline changes...the flash flood watch for Jo Daviess, Stephenson and Carroll counties has been extended until 10 AM Sunday morning. Through late this afternoon... A persistent decaying storm complex across Iowa will likely push sprinkles or some isolated showers south of I-80 and north of highway 34 through late afternoon in eastern Iowa. Tonight and Sunday... The persistent complex across Iowa today raises questions as to how storms will develop and evolve tonight. Two scenarios are possible tonight. What is common between either scenario is high moisture levels, unstable air aloft and forcing from a passing upper level disturbance that will result in heavy rainfall. Scenario 1 involves new storm initiation along the IA/MN border during the evening that moves southeast overnight and exits the area late Sunday morning. If this scenario occurs then the internal signal points to the heaviest rainfall occurring between highway 20 and highway 30 generally north of an Independence, IA to Sterling, IL line. Scenario 1 is what the current forecast is based upon. Scenario 2 would have new convection develop with the remnants of the current system across Iowa. If this occurs then the heavier rainfall would occur across southeast Iowa into west central Illinois. If scenario 2 occurs then the overall forecast message would need to be changed considerably. .LONG TERM...(Sunday Night through Saturday) ISSUED AT 312 PM CDT Sat Sep 14 2019 tarting the period off with adding some precipitation chances to the southern areas for Sunday evening. The front will be situated across the far southern part of the forecast area and with some convergence and moisture pooling along the front, felt there is enough of a chance for showers and thunderstorms to add a slight chance in for the evening hours. High pressure builds in at the surface through the day Monday with return floe being seen over the plains into Western Iowa as the upper level ridge is centered up and down the Mississippi River valley. The setup looks good for patchy to even areas of fog with good moisture at the surface under the inversion and mostly clear skies Sunday night into Monday. The areas with the weakest low level flow to support fog development will be across the northeast quadrant of the forecast area so have limited the mention of fog do those areas. Temperatures on Monday will be a bit warmer than on Sunday and will be well above normal in the 80s. Think that even if fog does form and holds on longer into the morning, temperatures should recover rather quickly to get those areas into the 80s. The big story for the week will be hot and humid. The upper level ridge sits in place through the week. Temperatures Monday through Wednesday will be warmest with highs in the mid to upper 80s and with dewpoints in the upper 60s to low 70s, it will be quite uncomfortable for this time of year. A few shortwave troughs will move through the flow to provide chances for thunderstorms beginning on Wednesday and continuing through the week. The chances for widespread thunderstorms is highest Wednesday night as the primary wave of shortwave energy moves across the area. Timing could change this to earlier or later, which will need to be watched for any stronger storm potential or heavy rain/flooding potential. Moving through the remainder of the week, there will be minor weak shortwave energy moving through the southwest flow across our area periodically, but timing those pieces of energy is not anything that can be done at this point with high confidence. Also, with high dewpoints providing decent instability will likely lead to at least some daily diurnal convection. Therefore thunderstorm chances are in the forecast through all periods. && .AVIATION...(For the 00Z TAFS through 00Z Sunday Evening) ISSUED AT 614 PM CDT Sat Sep 14 2019 Storms will move east through eastern Iowa and northern Illinois tonight as a warm front lifts over the region. Heavy rain, small hail and gusty winds can be expected as storms push through. I have conditions mainly VFR as far as cloud bases are concerned, but visibility may drop to under 1 mile in storms. The thunderstorms will exit the region in the 12Z to 15Z window Sunday morning, and a VFR dry day should develop by mid morning. && .HYDROLOGY... Issued at 1129 AM CDT Sat Sep 14 2019 Routed water moving through the river systems along with additional heavy rain potential tonight is causing forecast rises, many within bank rises, across the area. The hardest hit local basins have been the Pecatonica and Rock River basins and we are getting a better handle on the flows from rains that already fell, however there does remain a bit of uncertainty on how high the crests will be. The Pecatonica in Freeport is cresting currently and will fall less than a foot before starting to go up again as more water moves down from upstream. On the Rock, the forecast for the gage at Como has gone down this morning and the rate of rise has slowed, giving less confidence that the river will hit the flood stage of 12.5 ft even though it`s only a half foot from that level currently. Because of this, opted to hold onto the flood watch and will re-evaluate this afternoon. Downstream at Joslin, it may be noticed that the hydrograph is now showing the river to rise to 14.1 feet. Think the rise is going to be very near 14 ft, but don`t have enough confidence that it will reach or exceed 14 ft to put out a new flood warning for moderate flooding yet. Will continue to monitor. There is a chance for heavy rains tonight, if heavier rains fall than is expected, additional river flooding could occur. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...Flash Flood Watch through Sunday morning for Buchanan-Delaware- Dubuque-Jackson-Jones. IL...Flash Flood Watch through Sunday morning for Carroll-Jo Daviess- Stephenson. MO...NONE. && $$ UPDATE...Ervin SYNOPSIS...08 SHORT TERM...08 LONG TERM...Brooks AVIATION...Ervin
Area Forecast Discussion
National Weather Service Fort Worth TX
627 PM CDT Sat Sep 14 2019 .AVIATION... /00z TAFs/ Concerns: None major; VFR with east winds prevailing. Possible SHRA/TS tomorrow afternoon across central and southern Texas. VFR will prevail through the entire TAF valid period. High pressure across the region will keep chances for precipitation low, though a few showers and isolated thunderstorms may attempt to develop east and south of D10 airspace tomorrow afternoon. There is a small chance of a shower developing in the vicinity of the Waco terminal after 19-20Z, however the confidence of this is too low to include VCSH/VCTS in the TAF ATTM. Light east to southeast winds under 10 knots should persist through the period with diurnal CU between 060-080 tomorrow afternoon. Bonnette && .SHORT TERM.../Issued 1251 PM CDT Sat Sep 14 2019/ /Through Sunday Evening/ Tranquil and unseasonably warm weather is anticipated over the next 24 to 30 hours across North and Central Texas. There is a low potential for a few showers across East and North Texas, but this threat is far too low to include in the forecast. Ridging continues to dominate the weather across the Southern Plains early this afternoon. Surface high pressure was noted across parts of southeast Oklahoma at this hour, and this has resulted in an east to northeast flow regime across North and Central Texas. This afternoon, temperatures will climb into the mid 90s as boundary layer mixing continues. Some hi-res guidance does imply the potential for a few showers, but the 12 UTC FWD RAOB and RAP forecast soundings suggest that this potential is not worthy of a mention in the forecast. Tonight, clouds will diminish and light winds are forecast. This should foster a decent radiational cooling episode with overnight lows dipping into the 60s and 70s. Lows across the more urbanized areas may remain in the mid 70s. Overall, it should be a pretty pleasant overnight period. Sunday will feature another day of quiet weather, though low level moisture may increase some as an easterly wave currently across the Central Gulf of Mexico continues to churn westward. The potential for showers/storms still appears low, but there could be an increase in tropospheric moisture (particularly across East Texas), and this may result in a few more clouds. Regardless, it`s likely that temperatures will still climb into the mid to upper 90s with the warmest conditions across the Big Country (generally west of US HWY 281). Bain && .LONG TERM... /Issued 320 PM CDT Sat Sep 14 2019/ /Sunday Night through Saturday/ From Sunday Night through Tuesday, the upper level ridge will remain centered to our northeast with an upper level trough across the western half of the CONUS. In the Gulf of Mexico, a weak upper level disturbance will slowly meander along the Texas Coast, and then will likely dissipate around the middle of next week. However, the presence of this upper level disturbance will have transported higher moisture into the region with PWAT values slightly above normal for this time of year. This will yield some rain chances across mainly Central Texas Monday through Thursday, but some isolated or scattered showers and/or storms may creep into North Texas, too. Rain chances Monday through Thursday range from 20-30 percent across parts of North Texas, to 40-60 percent across parts of Central Texas. The reason for the increase in rain chances is largely do to increased consistency and confidence in rain reaching Central Texas. The coverage should be scattered for the most part, with possible small clusters occurring at times. This does not mean everyone will see rain, but some locations in Central Texas could receive half an inch or more of rain this week. Widespread severe weather is not expected but gusty winds, periods of heavy rainfall and possibly even some small hail will be possible. Temperatures will continue to be warm next week, but occasional winds around 10 mph will provide some relief. Generally look for highs in the lower to mid 90s with overnight lows in the upper 60s to mid 70s. Heat index values will approach 100 degrees at times next week, but are currently not expected to go much higher than that. We may see some slightly cooler daytime temperatures by the end of the week. The upper level ridge will continue to largely dominate our sensible weather heading into next weekend, while the principal storm track remains well to our north. Remnants of the weak disturbance that dissipates along the Texas Coast may be drawn north late in the week, allowing for scattered showers and storms to spread a little farther north. Widespread rain is still not expected, and unfortunately not everyone will see rain this week. JLDunn && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 74 98 75 97 76 / 5 0 0 0 5 Waco 71 99 74 97 74 / 5 0 5 10 10 Paris 71 96 73 94 72 / 0 0 0 0 0 Denton 73 97 73 96 74 / 5 0 0 0 0 McKinney 73 97 73 96 74 / 5 0 0 0 0 Dallas 77 99 76 97 77 / 5 0 0 0 5 Terrell 73 96 75 97 74 / 5 0 0 0 5 Corsicana 72 96 73 96 73 / 5 0 5 5 5 Temple 71 98 73 96 73 / 5 0 5 10 10 Mineral Wells 70 98 71 95 71 / 5 0 0 0 5 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 06/22
Area Forecast Discussion
National Weather Service Goodland KS
515 PM MDT Sat Sep 14 2019 .SHORT TERM...(This afternoon through Sunday Night) Issued at 1245 PM MDT Sat Sep 14 2019 Today... A slight chance for showers and thunderstorms will be possible this afternoon and evening mainly along and east of a line from Leoti to Gove to Hill City, Kansas. Forecaster confidence remains low on the potential for any storms to develop. However, if storms do develop, there is a chance that those storms could be severe with the greatest weather threat being damaging wind gusts up to 60 mph. With an upper-level trough progressing eastward through the Central Plains today, there could be some marginal support for ascent more towards central Kansas. That flow pattern paired with moderate instability with HRRR forecast CAPE values around 1000 to 1500 J/kg means that a small possibility for severe weather will be present this afternoon and evening. The timing for any showers and thunderstorms would be between 4 PM and 10 PM CDT. Afternoon highs for Saturday will generally be in the upper 80s to lower 90s. Winds will be fairly light and variable for this time of year except for the region where showers and storms may be possible where some southwesterly winds gusting to 20 kts will be possible through this evening. Tonight... Light and variable winds with clearing skies are expected tonight as the aforementioned upper-level trough moves out of the forecast area. Overnight lows tonight will be similar to the previous night with temperatures down to the lower 50s expected in Yuma County, Colorado increasing southeastward with lows in the middle 60s in Graham County, Kansas. With light winds, clear skies, and relatively moist air in place tonight, some patchy fog may be possible late tonight and into the early morning hours Sunday. The potential for fog will generally be limited to east of US Hwy 83 where there will be lighter winds and will be patchy at best. Sunday... Any fog which forms early Sunday morning will dissipate shortly after sunrise. Breezier southerly surface winds are expected tomorrow from the late morning through the overnight hours as a surface trough moves through the forecast area. Wind gusts will generally be up to 20 to 25 kts across the Tri-State area. Mostly clear skies are expected Sunday morning, however some partly cloudy skies are expected to move in from the west Sunday afternoon and persist into the overnight hours. No precipitation is expected Sunday at this time. Generally, Sunday will be a pleasant and warm early fall day with afternoon highs in the lower 90s. Sunday Night... Partly cloudy skies will stick around through the overnight hours Sunday and into early Monday morning, as well as breezy southerly surface winds with gusts up to 20 to 25 kts. No precipitation or fog is currently expected overnight Sunday as slightly lower humidity values are forecast for that time period. Overnight lows will only get down to the lower 60s farther northwest and the upper 60s farther southeast with the forecast area. .LONG TERM...(Monday through Saturday) Issued at 151 PM MDT Sat Sep 14 2019 Forecast concern will be winds Monday and chances of precipitation through the period. The rainfall forecast will be more difficult than normal due to model differences on mid/upper level features plus surface boundary positions which will be near or over the area. Satellite showing an amplified patter across the Pacific which then transitions to a more zonal/broad across the country. Monday/Monday night...Strong south to southwest flow aloft is in place. Tight pressure gradient along with 3 hour pressure falls nearing 5 mb will cause windy conditions. After collaboration with neighbors and loaded in Consmos for the winds. Models show a rather strong system approaching/moving through the area from the southwest. Also some weak jet lift in place. Some surface lift provided with a surface trough/dryline near the Colorado/Kansas border. Mid level moisture is available with 700 to 500 mb temperatures not high enough to cap the air mass as surface/layer cinh also show. There is an adequate amount of Cape. Storms that form will be high based but based on the above believe there is enough there for a few thunderstorms to form. Models show large amounts of Dcape and combined with the strong surface winds, strong and gusty outflow winds will be a big threat. The blend gave me no pops but did raise them to slight chance. Tuesday/Tuesday night...Models in general are in good agreement with a negative tilt shortwave system from the northern Great Basin into the Pacific Northwest. However, they differ on how fast and strong this system is. To start out the Ecmwf and Canadian are much slower/stronger/further south than the more open Gfs, and the fastest Nam. This trend continues through the period with the Ecmwf the slowest, the Canadian in the middle, and then the Gfs. Of course the Gfs is more in line with its ensembles even though it is still more amplified than them. Main lift looks further north than the day before but the northern stream shortwave will push a cold front to help with the lift. Like the small forecast blend pops. Wednesday through Saturday...Models keep the same general pattern of troughiness in the western portion of the country. However by the end of this period the models are not in strong agreement. Per the amplified pattern in place and the teleconnections mentioned in the PMDEPD, would support the more amplified solutions. Considering the model differences and surface boundaries around, it is hard to make a case to change the pops. Although there is potential for pops to be higher. So left the pops alone in this period. Also left the temperatures alone, despite a couple of frontal passages, the air mass does not look likes it changes much. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 515 PM MDT Sat Sep 14 2019 For KGLD and KMCK, vfr conditions through the period. Light and variable winds at taf issuance will continue overnight then increase from the south (KGLD) with gusts around 25kts expected Sunday afternoon. For KMCK winds become southeast 8-11kts after 18z Sunday. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...PATTON LONG TERM...BULLER AVIATION...99
Area Forecast Discussion...UPDATED
National Weather Service Mobile AL
628 PM CDT Sat Sep 14 2019 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION... 00Z issuance...VFR conditions the next 24 hrs. A large upper level low pressure system over the Gulf favors a continuation in scattered to broken high level cirrus streaming westward over the central Gulf coast. A mostly light northeast wind at MOB and BFM continues tonight while at PNS, light southeast winds become northeast overnight. A few shra, moving westward this evening over the interior, expected to stay north of the terminals. /10 .PREV DISCUSSION... /issued 359 PM CDT Sat Sep 14 2019/ NEAR TERM /Now Through Sunday/...An easterly low to mid level flow pattern will continue across the central Gulf Coast region tonight and Sunday on the southern periphery of a deep layer ridge of high pressure extending eastward across the Tennessee Valley and the Eastern Seaboard. Moisture will remain a little more enhanced over interior portions of southwest AL and southeast MS this afternoon, where precipitable water values will range between 1.6" and 1.8" per the latest RAP model guidance. A weak impulse moving west- southwestward toward central and interior southwest AL may aid in the development of isolated showers or thunderstorms over interior portions of the forecast area late this afternoon into early this evening, and will maintain a ~15% POP over these areas through early evening. A brief shower or storm may also develop along the seabreeze near the coast through around 7 PM or so. Clouds gradually decrease late tonight and overnight lows should range from around 70 degrees to the lower 70s inland, with mid to upper 70s along the immediate coast. Upper ridging will tend to build farther into central portions of MS/AL on Sunday. A more subsident airmass underneath this feature may tend to preclude convective development, although an isolated shower or storm cannot be entirely ruled out, especially near the coast along the seabreeze. Highs should range in the lower to mid 90s. /21 SHORT TERM /Sunday night Through Tuesday night/...A large upper ridge extending from the southeast states to across the Plains remains in place over the region while the northern portion advances into the eastern states. Tropical Storm Humberto will be initially located approximately 225 miles east of Jacksonville, Florida then continues further off into the western Atlantic through Tuesday night. A surface ridge remains in place over the eastern states through the period, which along with the western fringe of Humberto`s circulation will promote a light northerly surface flow over the area. Subsidence associated with the upper ridge will maintain dry conditions over the forecast area and also contribute to above seasonable daytime temperatures. Highs will be mostly in the mid 90s on Monday followed by mid to upper 90s on Tuesday. Lows will generally range from the lower 70s inland to the mid 70s at the coast. A low risk of rip currents is expected through the period. /29 LONG TERM /Wednesday Through Saturday/...An upper ridge will be in place over the eastern states and into the south central states through Saturday. A surface ridge strengthens from the mid Atlantic coast into the southeast states through the period, which causes a transition from a light northerly surface flow on Wednesday to an easterly flow on Thursday. This is what`s known as a back-door cold front, but despite the name only brings somewhat of a respite to the hot temperatures. This feature will be sufficient to produce isolated to possibly scattered showers and storms over much of the area on Thursday, but otherwise dry conditions prevail. Highs on Wednesday will be in the mid to upper 90s then highs each following day will be in the lower 90s. Lows Wednesday night range from the lower 70s inland to the mid 70s at the coast, then the following nights will see mid to upper 60s inland ranging to the lower 70s near the coast. /29 MARINE...A ridge of high pressure will extend southwestward along the northern Gulf through the remainder of the weekend, resulting in a continued light to moderate easterly wind flow over the marine area. Small craft may need to exercise caution again offshore late tonight into Sunday. A light to occasionally moderate east to northeast flow will prevail at night and early in the morning Monday before becoming light onshore by Monday afternoon. Seas remain elevated between 2-4 feet near shore and 3-5 feet offshore through Sunday, before gradually subsiding into early next week. /21 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...High Rip Current Risk until 5 AM CDT Sunday for ALZ265-266. FL...High Rip Current Risk until 5 AM CDT Sunday for FLZ202-204-206. MS...None. GM...None. && $$ This product is also available on the web at:
Area Forecast Discussion
National Weather Service Marquette MI
655 PM EDT Sat Sep 14 2019 .SHORT TERM...(This evening through Sunday) Issued at 404 PM EDT SAT SEP 14 2019 Water vapor imagery and RAP analysis show the shortwave that brought the widespread rain to the area late Thu into early Fri lifting into Quebec. In its wake, flow has become more zonal across the northern CONUS. In this flow, a well-defined shortwave is located vcnty of the ND/MN/Manitoba border. This wave will be the next feature of interest as it moves across the area late tonight/early Sun. Farther s, rather strong isentropic ascent/theta-e adv was driving another area of shra/tsra over IA. Closer to home, sunny skies have mostly been the rule this aftn across the fcst area. After a cloudy morning over the far eastern fcst area, clouds have now cleared out. Breezy winds are also beginning to settle down as pres gradient relaxes with arriving sfc high pres ridge. Aformentioned shortwave approaching the area tonight will make for an interesting and challenging fcst. In response to the shortwave, the rather strong isentropic ascent/theta-e adv driving convection across IA will shift ne toward Upper MI, though in a somewhat weakened state. This ne advancing isentropic ascent/theta-e adv is already causing a new area of shra/tsra development btwn KMPX and KDLH. Meanwhile, small upper jet streak associated with the shortwave will shift across Lake Superior while the leading edge of another jet streak translates from ND across MN to northern WI/western Upper MI by 12z Sun. Result is a coupling of the 2 jets (right entrance of one and left exit of the other) to enhance upper divergence over ne WI/Upper MI. Combined with advection of elevated instability into the fcst area of at least a few hundred j/kg, looks like a good setup for shra and some tsra to spread/develop across Upper MI tonight, especially central and eastern Upper MI. Given the forcing, wouldn`t be surprised if there are localized streaks of fairly hvy pcpn with some of the tsra, similar to what the cams are showing. If instability is on the higher end, NAM for example with up to 1000j/kg of elevated instability advecting toward Upper MI, estimated effective shear would be sufficient for a few organized storms that would pose a hail risk. Expect the shra/tsra to diminish w to e late tonight, leaving behind abundant low clouds for much of Sun. There may be some fog and patchy -dz during the morning, especially where light e to se winds are upsloping. Weak nnw to sse oriented sfc trof will move across the w half of Upper MI during the day on Sun. If there are sufficient breaks in the clouds during the aftn to allow for a little sfc based instability to develop, isold -shra may develop vcnty of the trof. .LONG TERM...(Sunday night through Saturday) Issued at 414 PM EDT SAT SEP 14 2019 After feeling like September in August, the next week or so will feel like August in September! Ridging will dominate most of the long-term period around the Upper Great Lakes with anomalous warmth as a result. There are a few rain chances this week but no significant systems. To start off Sunday night, surface high pressure will be overhead which will lead to cool overnight lows - but not particularly cold given warmer air advecting in aloft and NW cyclonic flow aloft both contributing to lingering cloudiness. Have lows getting into the mid to upper 40s west where more clearing is expected, and staying above 50 everywhere else. The west is also most likely to see some early morning ground fog, should any form. For now, have kept it all patchy. Despite some clouds around, the warming trend begins Monday. 12z 850 mb temps around 13-14 C, with additional warming during the day, suggests that highs in the mid 70s to around 80 are possible Monday even despite shallower mixing than we`d see in early-mid summer. The GFS continues to resolve a ridge roller or similar feature Monday night that triggers numerous showers, and the rest of the guidance continues to buck that trend. Reluctantly drew in slight chance POPs over the western arm of the lake and the Keweenaw but still not really believing anyone will see rain Monday night. The air aloft warms further on Tuesday. Depending on how many (if any) lingering clouds, Tuesday could be even warmer with highs in the low 80s west and central and mid to upper 70s east. With dew points in the 60s too, it will actually feel somewhat uncomfortable by Tuesday. The weather Tuesday night through Thursday then depends on just how stubborn the ridge over us is. All of the models indicate a weakness Tuesday night that mostly remains to our west but could spark off a few showers and thunderstorms over the far west. (The GFS breaks down the ridge quicker and soaks us Wednesday. Once again, did not buy into that solution.) Eventually though the ridge will weaken Thursday as a more potent mid-level short wave lifts northeastward from the Northern Plains into northern Ontario. It should drag a cold front across Upper Michigan Wednesday night or Thursday, but how exact timing and just how strong remain uncertain so mostly left NBM`s slight chance to chance POPs. Should be enough CAPE for thunderstorms with this front. High pressure builds in Friday as the upper-level ridge restrengthens. Models split on how long that high persists into next weekend so have left the NBM`s slight chance POPs in. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 655 PM EDT SAT SEP 14 2019 VFR conditions will prevail into the evening at all sites. Disturbance moving into the Upper Great Lakes will spread sct shra and a few tsra across Upper MI tonight. There is still some uncertainty in where these shra will occur, so only VCSH was included in the fcst. Right now, it appears KIWD and KSAW have the better chc of being impacted. Later in the night into Sun morning, expect a sharp drop in cigs with IFR developing at KSAW/KIWD and MVFR at KCMX. Fog may also develop. IWD will go back to VFR late on Sun while SAW stays down in IFR/LIFR while CMX will go to MVFR late. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 404 PM EDT SAT SEP 14 2019 After the recent windy conditions and gales on Lake Superior, a quieter weather regime will mostly prevail for the next several days. Winds are continuing to diminish w to e across Lake Superior this aftn as sfc high pres ridge is moving into the Upper Lakes. Winds across Lake Superior tonight are expected to be under 20kt, though there may be some gusts to 20-25kt across central and eastern Lake Superior late tonight/early Sun morning as a warm front advances ne toward Upper MI. Winds will diminish to under 15kt Sun aftn as pres gradient weakens. These lighter winds will then linger into Mon. Expect winds under 20kt on Tue before an increase in winds occurs on Wed ahead of an approaching cold front. Over the e half of the lake, southerly winds gusts could increase to 25-30kt at high obs platforms on Wed. Since cold front will weaken as it crosses Lake Superior Wed night/Thu, winds will diminish heading into Thu. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Beach Hazards Statement until 8 PM EDT this evening for MIZ006. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...Rolfson LONG TERM...RJC AVIATION...07 MARINE...Rolfson
Area Forecast Discussion
National Weather Service Las Vegas NV
859 PM PDT Sat Sep 14 2019 .SYNOPSIS...Sunday will bring one more day of above normal temperatures before a low pressure system dropping down from the Pacific Northwest moves across the southern Sierra and Great Basin on Monday bringing very windy conditions and significantly cooler temperatures. Another weather system will follow a similar track and bring more wind to the region Wednesday through Friday. && .UPDATE...Another quite evening across the area thus far with warm temperatures and light winds. Hires models have continued to show an outflow boundary working its way into southern Mohave County this evening from decaying thunderstorms over the FGZ/PSR CWAs. Evidence of this is showing up in the 8 pm observation data where southeast gusts up to 35 mph are being reported by a sensor on Highway 93 in far southeast Mohave County. The HRRR forecasts these outflow winds reaching into the Colorado River Valley later this evening and into southern Clark County overnight. As the outflow boundary moved across this sensor, temperatures dropped only about 3 degrees but surface dewpoint temps rose from around 40 degrees into the upper 50s. RAP analysis shows a tongue of PWATs around an inch pushing into far southern Mohave County but with limited instability. Radar returns to this point have been weak but I can`t completely rule out a light shower and/or a brief thunderstorm developing mainly along the boundary as it rolls through. No updates were made to the forecast for now. && .PREVIOUS DISCUSSION...257 PM PDT... .DISCUSSION...through next Saturday. The main focus of the forecast through Monday evening is the wind impacts expected from the incoming trough digging out of the Pacific Northwest. The latest high res model wind fields indicate the strongest belt of winds developing Monday afternoon and evening across the southern Sierra and Inyo, Nye, Lincoln and northwest Clark counties where gusts over 40 mph are likely. Even though periods of downslope winds with gusts over 40 mph appear likely in the southern Sierra and Owens Valley late Sunday afternoon through Sunday night, the best potential for dangerously high winds gusting over 60 mph will be Monday afternoon through early Monday evening and a High Wind Watch has been issued to highlight this. The strong winds, low relative humidity and dry fuels will create critical fire weather conditions. Winds are forecast to drop off fairly quickly Monday evening and there is no indication of strong post frontal winds pushing into southern Nevada since the upper level trough is forecast to lift away across northeast Nevada and Northern Utah. Tuesday will provide a brief break between systems before the next deep upper low is projected to roll across the Great Basin Wednesday through Friday providing another round of windy condition before lifting away to the northeast by next weekend. Aside from the wind, this pattern will keep temperatures subdued to near or slightly below normal. A secondary concern exists over northwest Arizona where convection this afternoon and evening around the central Arizona rim country is expected to produce gusty winds which may push outflow and some moisture toward the Colorado River Valley and up into central and southern Mohave County tonight. This will lead to possible isolated thunderstorms this evening over far southeast Mohave County near Wikieup and Alamo Lake then chances for thunderstorms will exists Sunday afternoon into Monday as somewhat moist and unstable air holds over the eastern half of Mohave County. && .FIRE WEATHER...A strong low pressure system will bring gusty winds to Inyo County California beginning Sunday afternoon then strong winds will spread across most of southern Nevada Monday...leading to critical fire weather conditions. A Red Flag Warning is in effect for Inyo County California zones from 3 PM Sunday until 9 PM PDT Monday. High downslope winds gusting to at least 60 mph will be possible along the eastern Sierra slopes and adjacent areas of the Owens Valley early Monday afternoon through early Monday evening. Southwest gusts over 35 mph will affect the mountains of Death Valley National Park from Sunday afternoon through Monday evening. A Red Flag Warning is in effect for most southern Nevada zones from 11 AM Monday morning until 9 PM PDT Monday evening. A belt of strong southwest winds gusting over 35 mph is forecast much of Nye, northwest Clark and Lincoln counties from late Monday morning through Monday evening. The strong winds will be accompanied by minimum RH values in the single digits to lower teens. && .AVIATION...For McCarran...Typical light drainage winds expected this evening, with light and variable winds for much of Sunday. Some outflow from Arizona thunderstorms may push into the valley after midnight tonight, but chances for this are decreasing. By Sunday afternoon, a southerly push could advance across the valley, with winds transitioning from light and variable to southerly around 8 to 12 kts. Southwest winds may begin increasing late in the evening with stronger southwesterly winds for Monday. The primary hazards of low-level wind shear and clear air turbulence look to be late Sunday evening through Monday. For the rest of southern Nevada, northwest Arizona and southeast California...Generally light winds expected overnight for much of the region. There remains an outside chance of gusty outflow winds impacting areas southeast of Interstate 15 tonight. Expect southerly winds to begin increasing across the region, especially the Owens Valley tomorrow, bringing low-level wind shear and clear air turbulence hazards. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ UPDATE...Salmen DISCUSSION/FIRE WEATHER...Adair AVIATION..................Steele For more forecast information...see us on our webpage: or follow us on Facebook and Twitter