Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/14/17

Area Forecast Discussion
National Weather Service Dodge City KS
757 PM CDT Thu Apr 13 2017 ...UPDATED AVIATION SECTION... .SHORT TERM...(This evening through Friday) Issued at 146 PM CDT Thu Apr 13 2017 Models remain in good agreement this afternoon with the track and timing of the upper low as it lifts north northeast across western Kansas early tonight. As this system lifts north northeast an area of rain showers along with a few embedded thunderstorms, located in northwest Oklahoma earlier this afternoon, will also lift north into south central and portions of western Kansas. Given the track of the upper low/trough along with the location of the better moisture return and forcing the areas that will have the better chance for accumulating rainfall still appears to be near the Oklahoma border and east of a Hays to Coldwater line. Based on the latest model runs the rainfall amounts from 7pm Thursday to 7 am Friday east of highway 183 is expected to range from one half to three quarters of an inch. Further west accumulations will be less than two tenths. After midnight this area of rainfall will begin to taper off from west to east. Any lingering precipitation in north central Kansas early Friday morning will quickly end and skies will clear. By the early afternoon a developing dry line will move into extreme western Kansas under some warm mid level temperatures. Concerned about the strength of the cap Friday afternoon but at this time can not rule out an isolated thunderstorm or two. Also can not rule out that if these storms develop then some hail up to the size of quarters or gusty winds will not also be possible late day or early Friday evening. West of this dry line Friday afternoon dry air and gusty winds will produce elevated to near critical fire danger levels near the Colorado border. Outdoor burning is not recommended in far western Kansas Friday afternoon. .LONG TERM...(Friday night through Thursday) Issued at 146 PM CDT Thu Apr 13 2017 Friday night this dry line will then remain nearly stationary or even retreat a little westward overnight as a surface cold front drops south across northwest Kansas. Lows Friday night ahead of this dry line will be mainly in the mid 50s to around 60 while west of the boundary the lows may fall back into the upper 40s in a few areas. On Saturday the cold front will overtake the dry line as it moves across southwest Kansas. Models are in reasonably good agreement with moving these surface boundaries into south central Kansas by late day. Adequate 0-6km shear and instability will be present late day for supercell development so severe thunderstorms Saturday afternoon will be possible along and ahead of this boundary. At this time based on the GFS it appears that hail greater than 2 inches, strong damaging winds and periods of heavy rainfall will be possible from these storms. Saturday night into early Sunday this frontal boundary will move south into Oklahoma where it will become stationary through early Monday. Models differing on location of this boundary late this weekend into early next week but they all do support moisture and lift north of this boundary which will result in another chance for precipitation across western and central Kansas. Given low confidence on where this boundary will be located am unsure how far north this next round of rain will spread so will stay close to the previous forecast on the northern extent of precipitation. The better chances still appear to be near the Oklahoma border and across south central Kansas. Early next week the surface boundary will lift north as a warm front as the precipitation chances end from west to east Monday night into Tuesday. Temperatures are expected to rebound back into the 80s on Tuesday. The next upper level trough will cross the central and northern Plains on Tuesday also and as it does a cold front will drop south into western Kansas where it is forecast to briefly stall out. North of this front mid week some cooler, more seasonal temperatures can be expected along with a chance for showers and thunderstorms. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 743 PM CDT Thu Apr 13 2017 Upper level system moving through the area this evening will accounts for a few isolated to widely scattered shower and weak thunderstorms. Other than that, some LIFR/IFR stratus may develop into the overnight based on the more pessimistic WRF NMM and HRRR runs, clearing GCK by 12-15 UTC and the remainder of the area later in the morning. A return to gusty south winds is in store for Friday. && .FIRE WEATHER... Issued at 146 PM CDT Thu Apr 13 2017 A dry line will move into far western Kansas on Friday. West of this dry line lower dew points and gusty winds will produce elevated to near critical fire danger levels near the Colorado border. Outdoor burning is not recommended in far western Kansas Friday afternoon. Winds Friday afternoon will be south southwest at 20 to 25 mph and relative humidity values will bottom out in the 18 to 25 percent range. && .PRELIMINARY POINT TEMPS/POPS... DDC 55 79 57 78 / 20 10 10 20 GCK 52 83 53 76 / 10 20 20 10 EHA 52 82 52 77 / 0 20 10 0 LBL 53 82 56 80 / 30 10 10 10 HYS 55 79 60 75 / 40 10 10 10 P28 57 77 60 78 / 50 10 10 30 && .DDC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...RB LONG TERM...RB AVIATION...Russell
Area Forecast Discussion
National Weather Service Houston/Galveston TX
922 PM CDT Thu Apr 13 2017 .DISCUSSION... Winds have begun to decouple and light SSE winds expected overnight. Sfc dew pts are lower than last night but damp ground, light winds and generally clear skies will allow for some patchy fog prior to sunrise. The SREF is quite aggressive with fog potential over the western half of the region. Will add some patchy fog to the wx grids based primarily on the SREF. Models are showing a weak short wave moving across SE TX on Friday. Moisture levels look meager but two narrow ribbons of deeper moisture noted near Galveston Bay and Matagorda Bay with values peaking near 1.25 inches might be enough to spark a few showers. Precip is supported by the HRRR and the TT WRF so will introduce isolated showers for Friday over mainly SE 2/3rds of the region. Temps look on track for both tonight and Friday so no changes there. Rest of the forecast looks great so no other changes planned at this time. 43 && .PREV DISCUSSION... /ISSUED 629 PM CDT Thu Apr 13 2017/ AVIATION... Expecting mainly VFR this evening. A low-level inversion will set up after sunset and will lay the foundation for at least a scattered MVFR deck for most locations overnight tonight. A low- level jet feeding into the hill country from the lower and middle coastal areas will help IFR conditions to develop at KCLL by 09Z. Any other MVFR conditions that do develop will likely be due to light fog between 09Z and 14Z and then mainly from KIAH north to KUTS. The SREF probabilities and model sounding forecasts also show the possibility for patchy ground fog at KSGR and KLBX between 08Z and 12Z. The low-level inversion should break around 15Z and expect any IFR to MVFR conditions to lift afterwards. Winds do not appear that they will get as breezy as occurred today. The NAM12 surface and 925mb wind forecasts stay near or below 10 knots through the afternoon period. May see some slightly higher surface winds at KCLL due to the tighter surface pressure gradient over the adjacent hill country area Friday afternoon. 40 PREV DISCUSSION... /ISSUED 350 PM CDT Thu Apr 13 2017/ DISCUSSION... Model guidance and MOS values support low temperatures for this evening dropping into the low 60s for our inland counties, and upper 60s along the coast. The chances for fog development this evening have decreased as drier air continues to filter into the upper levels of our atmosphere. Forecast soundings should plenty of dry air aloft, though there is still some slight saturation in the lower levels. Short term guidance such as the SREF and HRRR are also in disagreement regarding potential lower visibility coverage. Although the winds should weaken overnight to less than 5 mph, if fog does develop it will be fairly isolated. Light winds will remain out of the southeast and continue to stream in Gulf moisture overnight keeping dewpoints upper 50s and lower 60s. Dewpoints will lower slightly on Friday, as conditions dry out with the high pressure system in control, which should hold tight through Saturday. Upper level pressure fields also show a coastal low moving into the northwestern corner of the Gulf of Mexico from the south early Saturday. As this low shifts into the area, there will be an enhanced chance for precipitation along the eastern side of this low, as moisture funnels in and provides additional ascent in this region. The ECMWF and GFS are both in agreement with producing QPF just to the east of our eastern counties, mainly between 18-00Z Saturday. Because of the uncertainty of how this coastal low will propagate, and the potential tightening in pressure gradient as this system moves north, confidence is low on where this precipitation will set up. Therefore, adjusted PoPs up slightly along the eastern zones of our CWA to account for the possible shower and thunderstorm development Saturday afternoon if this system stays more to the west than what the models solutions were suggesting in the 12Z runs. Another round of precip will be likely Sunday night into Monday, as an upper level shortwave moves across SE TX. Model guidance is not in agreement regarding whether this shortwave strengthens enough to become a cut off low. This disturbance will continue to send higher values of positive vorticity across SE TX beginning late Sunday night around 18Z and into early Monday. Another vorticity maximum moves through late Monday into Tuesday as well, and precipitable waters increase to between 1.25-1.5 inches. Therefore, carrying higher PoPs Monday and Tuesday, until the shortwave finally moves off to the northeast early Wednesday. Wednesday through Friday will be a drier period. Models are picking up on the next frontal system moving through early next Saturday. Recent model runs have the GFS moving the front through slightly earlier around 06Z, in comparison to the ECMWF which bring the front into the region closer to 12Z Saturday. Hathaway MARINE... Southeast winds (generally in a 10 to 15 knot range during the day and up to around 15 knots at night) and seas at 3 to 5 feet will continue for the end of the week and through the upcoming weekend as high pressure persists off to our east. Models do show this pattern continuing for much of next week. 42 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 62 82 62 83 65 / 10 10 10 10 10 Houston (IAH) 63 82 64 83 67 / 10 10 10 10 10 Galveston (GLS) 70 78 70 79 71 / 10 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$
Area Forecast Discussion
National Weather Service Sacramento CA
850 PM PDT Thu Apr 13 2017 .SYNOPSIS... Drier weather Friday and Saturday, then additional storms expected Sunday into next week. && .DISCUSSION... Active afternoon with scattered thunderstorms across the Central Valley and surrounding foothills. Many reports of pea sized hail with several stronger storms producing larger. dime-sized, hail. Severe thunderstorm developed near Smartville which was showing strong couplet at multiple levels on radar. Activity is decreasing this evening as upper trough axis is shifting east into the Great Basin. Latest HRRR showing decreasing snow showers over the mountains of Western Plumas and Sierra Nevada this evening with showers subsiding most areas after midnight. Local additional accumulations of a few inches possible on portions of I-80 through the evening. Drier weather with warming expected over Interior NorCal Friday and Saturday as upper level ridging moves through. High temps Saturday expected into the upper 60s to lower 70s for the Central Valley with 40s to 60s for the mountains and foothills. Models painting similar picture with next Pacific storm spreading precip into western portions of the forecast area Easter morning and across all of Interior NorCal by Sunday afternoon. Model QPFs differ with EC showing higher amounts in the Central Valley while GFS is significantly wetter in Western Plumas and Sierra Nevada. System likely to cause travel impacts in the mountains above 5000 to 6000 feet. Additional weaker systems follow late Monday and Tuesday with a stronger system forecast towards the middle of the next week. PCH $$ .EXTENDED DISCUSSION (Monday THROUGH Thursday) Northern California will remain under moist southwesterly flow early to mid next week. Periods of precipitation will be likely across most of the region, though the timing of individual shortwave troughs will likely remain uncertain for some time. As such, we`ve broad brushed the forecast with higher than climo chances of precipitation. Longer range models indicate drier weather toward the end of next week. JClapp/Dang && .AVIATION... Upr trof movg E as upr rdg in EPAC movs inld. VFR conds ovr Intr NorCal nxt 24 hrs exc isold MVFR/IFR/LIFR conds ovr Siernev in snow shwrs til 12z Fri. Sn lvls 035-040 amsl. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$