Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/02/19


Area Forecast Discussion
National Weather Service Bismarck ND
1033 PM CDT Fri Nov 1 2019 .UPDATE... Issued at 1033 PM CDT Fri Nov 1 2019 Low level frontogenesis is waning with light snow shrinking in areal coverage over the southern James River Valley. This should end within the next couple hours. Updated PoPs using the RAP and current radar. The sky is trending clear in the west as low level warm air advection/westerly winds continue to bring in drier air, along with a brief period of subsidence aloft. For central ND, expect mostly cloudy conditions through most of the night. UPDATE Issued at 808 PM CDT Fri Nov 1 2019 Updated PoPs through 07z Saturday as an area of 925mb-850mb frontogenesis depicted by the RAP13 lines up perfectly with the band of light snow from Sheridan to portions of Burleigh and Kidder counties, and into Logan and McIntosh counties. This area is forecast to continue this evening, but slowly shrink through 07z before ending. Hence PoPs were updated. UPDATE Issued at 548 PM CDT Fri Nov 1 2019 Latest water vapor imagery along with the RAP13 show a couple of mid level shortwaves embedded with a northwest flow aloft rotating through central ND. Per BUFKIT soundings, weak forcing with the shortwave, but steep low level lapse rates within a cold/moist airmass continues to produce areas of light snow across central ND. This will continue into early evening, then slowly wane overnight. Low level warm air advection begins across the west tonight and propagates through central ND Saturday. Stratus will gradually lift tonight through Saturday from west to east as low level drier air briefly takes control. && .SHORT TERM...(This evening through Saturday) Issued at 233 PM CDT Fri Nov 1 2019 Light snow ending this evening highlights the short term forecast. A band of light to moderate snow generally between US Highway 83 and ND Highway 3 as of 1915 UTC will continue to propagate southeast in association with an impulse rotating around the upper level low across southwest Ontario. A quick half inch of accumulation is possible. Strong winds this afternoon will decrease this evening with a weak surface ridge building across western and central North Dakota tonight. Saturday is expected to be quiet, but, cloudy under the upper level jet in northwest flow aloft. Saturday may have the warmest temperatures over the next 7 days with highs in the upper 30s and lower 40s. .LONG TERM...(Saturday night through Friday) Issued at 233 PM CDT Fri Nov 1 2019 A significant cool down beginning Tuesday and continuing through Thursday highlights the extended forecast. This cool down is highlighted well by the CIPS temperature anomaly analogs and the very low NAEFS 700 mb and 850 mb temperature anomalies with two cold high pressure systems building across the Northern Plains under continued cyclonic northwest flow aloft. Widespread high temperatures only in the teens and 20s are forecast for Wednesday and Thursday, with sub-zero morning wind chills possible. Regarding precipitation, a rain and snow mix is possible Sunday into Monday, and snow again Tuesday with two rapidly propagating waves embedded in the northwest flow. Light snow accumulations are possible. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 548 PM CDT Fri Nov 1 2019 Generally low VFR cigs with very brief periods of MVFR cigs can be expected through 06z Saturday for all the terminals, then after 06z, the western terminals will become VFR while there will still be hit and miss MVFR cigs for KMOT/KBIS/KJMS from 06z-12z. However, will forgo any MVFR tempo group for cigs at this time due to the brevity and uncertainty at any one terminal. Did use a tempo MVFR vsby group in light snow for KBIS and KJMS early this evening. VFR cigs expected at all terminals 12z Saturday through the end of this taf period, except for KXWA/KDIK where another surge of MVFR cigs will arrive by around 23z Saturday. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...PA LONG TERM...PA AVIATION...KS
Area Forecast Discussion
National Weather Service Dodge City KS
600 PM CDT Fri Nov 1 2019 ...Updated aviation discussion... .SHORT TERM...(This afternoon through Saturday night) Issued at 1130 AM CDT Fri Nov 1 2019 Strong north winds were overspreading SW Kansas at midday, with the strongest winds as expected across the western zones and US 83 corridor. Winds gusts to near 40 mph will be common (already observed at Garden City) the next few hours as strong high pressure builds south from Wyoming. The latest HRRR shows the cold front clearing the SE zones by 5 pm. Despite full sunshine, modest cold air advection will keep temperatures struggling in the 40s through the afternoon, except some lower 50s near the Oklahoma border. After 4 pm, winds will begin diminish quickly as the pressure gradient weakens. Strong surface high pressure will dive essentially due south tonight, ending up centered from far SW Kansas to West Texas at sunrise Saturday. This will keep a W/NW breeze and a downslope component maintained overnight, which will interfere with otherwise near ideal radiational cooling. At any rate, it will be quite cold tonight, with morning lows averaging about 15 degrees below normal. Sunrise temperatures teens west to 20s east. Full sunshine again on Saturday, with 0% sky grids continuing. Surface high in West Texas at sunrise will move to near Dallas by 7 pm, allowing return flow and SW winds of 15-25 mph to resume by early afternoon. Still recirculating continental polar air, so temperatures will only show modest improvements into the lower to mid 50s. .LONG TERM...(Sunday through Friday) Issued at 150 PM CDT Fri Nov 1 2019 A long stretch of dry weather is expected Sunday through Tuesday. Model guidance is converging on a strong cold front and a strong surge of much colder air during the Wednesday to Thursday time range. Sunday will be a pleasant fall day with full sun, light winds less than 10 mph, and afternoon temperatures within a few degrees of 60. Dry NW flow aloft will continue Monday, with a barely perceptible minor dry cold front supplying a light NE breeze with little if any cooling from Sunday`s readings. Max temperature grids from the NBM for Tuesday, in the 50s, are likely too cool, with 12z ECMWF showing 850 mb temperatures rebounding to near +10C beneath increasingly zonal flow aloft. 12z MEX guidance looks too cold, and suspect 60s will be attainable Tuesday afternoon. Wednesday and Thursday are starting to look much colder (likely colder than shown by current forecast). 12z ECMWF depicts a 1046 mb arctic surface high centered over SE Alberta at sunrise Wednesday, with the initial cold front boundary slicing through SW Kansas daylight Wednesday. 12z ECMWF 850mb thermal fields strongly suggest non-diurnal temperature trends downward on Wednesday. The dry forecast will probably end by late Wednesday, with overrunning/stratus and a light wintry mix behind the cold front, most likely south and east of Dodge City. Given continued W/NW flow aloft, confident any heavy precipitation will remain southeast of SW KS (Oklahoma, W TX). 12z ECMWF depicts an impressive cold 1046 mb surface high in central Nebraska sunrise Thursday. This will force cold Canadian air to wedge down the high plains, and model guidance (NBM) has lowered Thursday`s afternoon temperatures to the 30s. Pending stratus, it may be even colder than that. This cold airmass looks highly progressive, such that return flow, south winds and moderating temperatures are expected Friday. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 600 PM CDT Fri Nov 1 2019 Gusty north winds will drop off rapidly toward sunset then switch to a west to northwest direction at 10 knots or less overnight. Surface high pressure over eastern Colorado will move into the Texas Panhandle by Saturday morning. This will bring southwesterly winds to the terminals on Saturday with some gusts to around 20 knots possible during the afternoon hours. && .PRELIMINARY POINT TEMPS/POPS... DDC 22 53 27 59 / 0 0 0 0 GCK 19 52 23 59 / 0 0 0 0 EHA 21 54 27 60 / 0 0 0 0 LBL 21 54 24 60 / 0 0 0 0 HYS 24 54 26 57 / 0 0 0 0 P28 27 56 30 60 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Turner LONG TERM...Turner AVIATION...Gerard
Area Forecast Discussion
National Weather Service Marquette MI
755 PM EDT Fri Nov 1 2019 .SHORT TERM...(This evening through Saturday) Issued at 305 PM EDT FRI NOV 1 2019 As a shortwave crosses N MN today, the attendant sfc trough is just out ahead of it. RAP analysis at 18Z has the trough axis stretching from the tip of the Arrowhead to LNL to STE. Upper trough is progged to dig ESE across the region through tonight while the sfc circulation will deepen to the north of Lake Superior. Light rain/snow on radar this morning into the early afternoon over the western and southern UP at about 4500+ ft AGL did not seem to be reaching the ground for the most part as lower level dry profiles took some time to saturate. Dew point depressions ranged from 6-13 degrees (even higher at some RAWS sites) and have only recently begun to fall. IWD and ESC both reported light rain early this afternoon and a quick peek at forecast soundings confirms that the saturated layer remained too warm for ice nucleation. This will change as we head through the evening and CAA continues while low level moisture increases. Webcam images confirm snow is falling as of 19Z in some locations near southern Houghton and Baraga Counties. Model guidance indicates the best chance for heavier precip along the axis of synoptic forcing will come later this afternoon into the evening over the far eastern fringes of the CWA as SW winds provide some enhancement off of Lake Michigan. However, much of this influence will be felt east of our area and this will be short-lived anyway with winds quickly veering due westerly between 00-03Z. The more significant precipitation will gradually build over the west tonight as 850 mb temps cool to around -8C. Cannot completely rule out isolated freezing rain/drizzle mixing in over the interior this evening into early tonight as saturated layer may not cool below -8 to -10 C before sfc temps cool below 0C. No ice accumulation is expected. Some orographic enhancement of snow along the spine of the Keweenaw and the Porkies is also expected. Expecting this to be rather low SLR snow for lake effect (10-15:1) as best lift and saturation will be below the DGZ. These snow showers will continue over the western UP off and on tonight through tomorrow, with accumulations by 00Z Sunday of 1-4". An isolated 5" report in the vicinity of Twin Lakes is not out of the question. At times Saturday, there will be enough of a northerly component to the winds east of Munising to bring lake effect precipitation to the region north of Newberry, however with sfc temperatures rising into the upper 30s some rain may mix in at times and snow accumulations will be suppressed, likely maxing out around an inch. Expecting overnight lows in the mid to upper 20s inland and near 30 lakeside, and it wont warm up much Saturday with highs in the low to mid 30s west and upper 30s to near 40 east. .LONG TERM...(Saturday night through Friday) Issued at 230 PM EDT FRI NOV 1 2019 Upper air pattern consists of a 500 mb trough over the lower Great Lakes 00z Sun with a ridge off the west coast. Upper air pattern changes little for this forecast with a shortwave moving through Sun night into Mon. Did not mane too many changes to the going forecast overall. In the extended, the GFS and ECMWF show a broad 500 mb trough across most of the U.S. except for ridging on the west coast 12z Tue. A shortwave in the upper trough will move into the upper Great Lakes 12z Wed. This shortwave digs into the Great Lakes region 12z Thu and into the lower Great Lakes 12z Fri. Temperatures stay well below normal for this forecast period. No big storms seen with plenty of smaller lake effect episodes for this forecast period and will be mostly snow. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 741 PM EDT FRI NOV 1 2019 Throughout the TAF period, expect periodic snow showers to persist at KIWD and KCMX, with KSAW eventually starting to see those chances move in overnight, albeit VCSH given the uncertainty of whether or not more direct impacts will be realized there. A fairly prolonged reduction in categories can be anticipated at KIWD and KCMX, primarily due to ceilings, although visbys may also take a hit overnight into the early morning hours as the peak of snow showers materializes. For Saturday at KSAW, have taken a bit more of an optimistic approach by midday, but should be noted that borderline M/VFR ceilings will persist there as well. W-SW winds this evening will become more westerly as the night progresses. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 305 PM EDT FRI NOV 1 2019 Southwesterly winds across the lake today of between 20 and 25 knots will shift to westerly tonight and eventually NW Saturday as a cold front is expected to push west to east across the lake. Expect wind speeds to range between 20 and 30 knots behind the front. Winds back west to southwest 15 to 20 knots on Sunday and below 15 knots Sunday night ahead of another wave approaching from the west. Monday through Tuesday, there does appear to be a few waves pushing across the lake. Therefore, is does look likely that we will see winds early next week ramp up to 25 to 30 knots as early as Monday night, depending on the track and strength of these waves. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...KCW LONG TERM...07 AVIATION...lg MARINE...KCW
Area Forecast Discussion
National Weather Service San Francisco Bay Area
429 PM PDT Fri Nov 1 2019 .SYNOPSIS...A Frost Advisory has been issued for the North Bay Valleys and a Freeze Warning has been issued for the Southern Salinas Valley and surrounding interior Monterey / San Benito Counties tonight into Saturday morning. Cool to cold overnight temperatures will continue for the next several nights. Otherwise, generally quiet weather is anticipated for the next week with warm daytime highs. Mainly light winds and dry conditions are expected through at least the end of next week. && .DISCUSSION...as of 02:05 PM PDT Friday...Conditions overall are little changed from 24 hours ago. Temperatures across the interior are running a few degrees warmer than this time yesterday while near the coast temps are similar to slightly cooler. Sunny skies, light winds, and temperatures in the 60s and 70s are creating very pleasant conditions for any outdoor activities. These temps are 5 to 10 degrees above normal for early November. The atmosphere remains very dry and while winds have decreased, dry conditions could still allow fires to start. Temperatures will plummet after sunset due to ideal conditions for radiational cooling. Lows tonight are forecast to once again become cold across the interior, although perhaps not quite as cold as previous nights. The air mass aloft is slowly warming and low level moisture is forecast to creep upwards as offshore flow weakens. Have issued a Frost Advisory for the North Bay Valleys and a Freeze Warning for the Southern Salinas Valley and surrounding interior Monterey / San Benito Counties. The atmosphere remains dry so frost will likely be patchy, but temperatures will be cold and vulnerable populations and pets will be at risk from the cold temperatures. Cool overnight low temperatures are once again expected across other inland valleys, with mid 30s to lower 40s. Near the Bay shoreline and coast, temps will drop into the lower 40s to lower 50s. Hilltop temperatures will remain mild in the 50s due to warm air aloft. Similar high temperatures are expected on Saturday. A ridge of high pressure over the eastern Pacific will expand eastward on Sunday and Monday. An uptick in onshore flow is which could lead to slightly cooler high temperatures along the coast and moderating low temperatures. As the ridge builds inland high temps away from the coast will remain nearly the same. Dry conditions, sunny skies, and above normal temperatures will prevail through next week as high pressure dominates the weather pattern. Models have continued to trend dry next weekend with ridging now favored to prevail. Temps could warm to well above seasonal norms as high pressure strengthens late in the week. No significant offshore wind events are expected through the end of next week, helping to mitigate fire weather concerns somewhat. However, until we receive a return to winter rainfall, our fire season will continue. && .AVIATION...as of 04:29 PM PDT Friday...for 00z TAFs. VFR conditions with mainly clear skies through the period as a large dry airmass remains overhead. The HRRR vertically integrated smoke model shows smoke from the southern CA fires drifting northward offshore this evening before moving into the Bay Area tomorrow morning and North Bay by the afternoon. This may create some slant range visibility issues, but not at this time expecting impacts at the surface. Winds will remain generally light this afternoon around 10 kt or less before winds become calm overnight. NW winds in the afternoon along the coast and offshore winds inland. Vicinity of KSFO...VFR with clear skies and generally light winds. Expecting winds to turn W to NW over the next couple of hours but remain at or less than 10 kt. Winds will become calm overnight. SFO Bridge Approach...Similar to KSFO. Monterey Bay Terminals...VFR with NW to N winds around 10 kt this afternoon before winds ease and turn SE overnight. && .MARINE...as of 02:09 PM PDT Friday...Clear skies with light northwest winds persist today and will remain through the weekend. Light mixed seas with a moderate period northwest swell and a smaller southerly swell. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tngt...Freeze Warning...CAZ516>518 Frost Advisory...CAZ506 && $$ PUBLIC FORECAST: ST AVIATION: AS MARINE: DK Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea