Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/06/19

Area Forecast Discussion
National Weather Service Charleston SC
1013 PM EST Tue Nov 5 2019 .SYNOPSIS... A cold front will pass through tonight. High pressure will return Wednesday, before a stronger cold front crosses the area Thursday night into Friday. High pressure will build in over the weekend and prevail into early next week. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... As of 1010 PM: IR satellite showed a band of low clouds sliding east across the Midlands, these clouds are likely associated with the cold front. As the front approaches the forecast area, cloud bases should lower below 1 kft. In addition, very low values of sfc condensation pressure deficits indicate that fog will develop along and ahead of the front. I will update the forecast to add fog to the forecast through most of the night. As of 825 PM: KCLX indicated that the inland showers have largely dissipated over the past half hour. The rest of the night should remain rain-free. It appears that low clouds and possibly patchy fog will develop over the coastal areas late tonight. I will update the forecast to reduce PoPs this evening and increase cloud cover tonight. As of 650 PM: KCLX detected a developing line of showers across the inland counties of GA. CAMs indicate that these showers will continue into the mid-evening hours and then dissipate. I will update the forecast to adjust PoPs and Wx to the current radar and model trends. Otherwise, the current forecast appears on track. Previous Discussion: The coastal trough will slowly shift east farther off the coast this evening. Meanwhile a cold front will sweep through from the northwest later tonight. Although the strongest convergence remains well offshore with the coastal trough, weak instability has developed over land areas this afternoon and will support isolated showers through early this evening. Temperatures will not drop much lower than last night though some drier air will begin working its way into the area late. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Wednesday: Aloft, a zonal flow will prevail. At the sfc, high pressure centered over the Mid-Atlantic states will wedge southward Wednesday with north/northeast winds keeping all areas dry, but slightly cooler than the previous day. In general, highs should range in the low/mid 70s, warmest across Southeast Georgia. Wednesday night lows should range around 50 well inland to mid/upper 50s closer to the coast. Thursday and Friday: Aloft, a zonal flow will persist through much of day Thursday before a large trough of low pressure digs over the East Conus. At the sfc, high pressure will gradually weaken ahead of a strong cold front advancing toward the area late. Expect winds to slightly veer more onshore during the day and temps to warm a few degrees higher with some warm air advection well ahead of the front. A few models suggest some isentropic lift spawning showers Thursday afternoon/evening, mainly across Southeast Georgia. However, the bulk of precip activity is expected to arrive near the timing of the cold front Thursday night into early Friday. PWATs peaking near 1.50- 1.75 inches along with weak instability suggest the bulk of precip activity to be in the form of numerous to potentially widespread showers along/ahead of the front. However, a few thunderstorms can not be ruled out near the immediate coast, especially in Southeast Georgia until fropa. Thursday night temps should remain mild with clouds in place and fropa late. In general, lows should range in the low-mid 50s away from the coast to around 60 degrees at the coast. By daybreak Friday, the bulk of precip should be shifting offshore as colder high pressure builds across the region. High temps will be noticeably cooler Friday afternoon, generally ranging between the low/mid 60s. By the evening, most areas should be dry, especially away from the coast. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A cool and dry fall weekend on tap. Models are in good agreement that high pressure will dominate the surface weather pattern over the weekend into early next week. Aloft, large scale troughing will persist. Plenty of sun is expected with minimal rain chances. Late in the period and beyond (Monday night into Tuesday), another strong cold front is progged to cross the area. Temperatures will generally be below normal, although will be moderating through the period. The coolest nights of the season thus far are expected Friday and Saturday night. We will need to watch for frost/freeze concerns. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... Prior to the 0Z TAFs, KCLX detected a developing line of showers across the inland counties of GA. CAMs indicate that these showers will continue into the mid-evening hours and then dissipate. The primary concern for the 0Z TAFs will be the placement, timing, and intensity of restrictive ceilings tonight. MOS and forecast soundings indicate the IFR to LIFR conditions will develop after midnight. In fact, HRRR sfc condensation pressure deficits fall to around 1 mb after 5Z. I will forecast MVFR ceilings between 4-5Z and will TEMPO a period of at least IFR ceilings between 6-10Z. Building high pressure should support steady NE winds by mid-day Wed. Extended Aviation Outlook: Mainly VFR through the middle of the week. There is a low chance for flight restrictions due to low cloud ceilings Thursday. Greater chances for flight restrictions are possible late Thursday through Friday due to showers along a passing cold front. VFR conditions should return Saturday and persist into Sunday. && .MARINE... Northerly winds will quickly increase after midnight following the passage of the cold front. Some gusts to 25 kt are possible in the Charleston nearshore and GA offshore waters closer to daybreak Wednesday where we have Small Craft Advisories beginning. Wednesday through Sunday: High pressure will build across the waters in wake of a cold front, leading to an enhanced pressure gradient and higher winds/seas Wednesday. Small Craft Advisories will be ongoing for northern South Carolina waters and offshore Georgia waters through the day, before conditions gradually improve Wednesday night. Winds/seas should then remain below Small Craft Advisory levels for much of the day Thursday before a strong cold front sweeps through the area Thursday night into early Friday. Strong cold air advection behind the front will likely cause winds and seas to deteriorate rapidly. Small Craft Advisories will likely be needed for all coastal waters, but there is also a potential for gale force wind gusts across some of the waters. Gale Watches and/or Warnings could eventually be needed with peak conditions occurring Friday night into Saturday, but conditions appear to fall just short of Gale criteria. Winds/seas should then weaken/subside as high pressure settles across the region Sunday. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...Small Craft Advisory from 4 AM Wednesday to 6 AM EST Thursday for AMZ350-374. && $$ NEAR TERM...NED SHORT TERM...DPB LONG TERM...ETM AVIATION...NED MARINE...DPB/JRL
Area Forecast Discussion
National Weather Service Duluth MN
957 PM CST Tue Nov 5 2019 .SHORT TERM...(This evening through Wednesday night) Issued at 220 PM CST Tue Nov 5 2019 Unseasonably cold temperatures continue through Thursday with high temperatures roughly where low temperatures should be this time of year. A broad 500-mb trough sits over much of southern canada and the northern United States, bringing cold air from Canada down into the northern Plains with northwesterly flow. Drier air will move in tonight as high pressure influences the region, which will help to clear out some of the clouds for northern parts of the area tonight. An area of low pressure will pass through Iowa tonight with 500-hPa cyclonic vorticity advection and 850-hPa warm air advection in southern minnesota bringing an area of snow just to the south of our region tonight into Wednesday morning. Most short-term guidance suggests snow will stay well to the south of our region, but there`s a slight chance that some light snow could affect our far southern borders. The HRRR, NAM, and RAP models suggest there could be a little light snow for southern portions of Price county Wednesday morning, but impacts from this should be minimal. This system will bring mostly cloudy to overcast skies to our region overnight, especially along and south of Highway 2. Areas to the north should stay partly cloudy. Low temperatures will reach the middle teens tonight. Winds will become northwesterly on Wednesday as a series of 500-mb short waves move through, bringing in a reinforcing blast of cold air from the north. There could be a few light snow showers associated with this primarily during the late afternoon. The biggest concern will be some lake effect snow showers developing late Wednesday evening and overnight into Thursday morning downwind of larger Minnesota lakes and along the South Shore of Lake Superior with northwesterly winds. The NAM model even suggests that bands off Lake Winnipeg may reach down into our CWA, and with 850-mb temperatures as low as 17C, this seems possible. Not anticipating any high amounts from this, but certainly a coating to an inch is possible...maybe locally more if any bands persist over the same area for several hours. Otherwise, high pressure will move in with partly cloudy skies, at least for areas not affected by lake effect. Low temperatures will hover around 10F, with some single digits possible as well. .LONG TERM...(Thursday through Tuesday) Issued at 220 PM CST Tue Nov 5 2019 Cold and mainly cloudy pattern through the long term forecast period. After well below normal lows in the single digits above zero on Thursday night, temperatures gradually trend warmer into Saturday as a warm front approaches from the west. A cold front then move from north to south on Saturday into Sunday leading to a chance for light snow accumulations (less than an inch) and will begin an even colder stretch of weather into early next week. Highs will be as cold as the teens and lows in the single digits above zero to nearly zero for some spots in northeast Minnesota. On the synoptic scale a broad upper-level ridge over the west coast will support additional intrusions of cold air from Canada across the Midwest/Great Lakes through the next 7-10 days. This will cause occasional low chances for light snow and below normal temperatures. Late-week a broad area of high pressure will be centered over the Upper Mississippi River Valley on Thursday, building east towards the Ohio River Valley on Friday. This will lead to partly cloudy skies Thursday clearing out Thursday night and causing lows in the single digits to low teens. Clouds then increase on Friday as a broad warm front approaches from the west leading to slightly warmer temps, highs in the upper 20s to low 30s then as warm as the upper 20s to mid 30s on Saturday. Late Saturday into Sunday a strong cold front approaches from the north with 850mb temps as cold as -20C arriving by Sunday night across the Northland, near record values per INL sounding climatology and temperatures that would be considered well below normal even in Jan/Feb. Any snowfall along and ahead of the cold front Saturday will be light, up to an inch or so of snow possible in most spots, except on the south shore of Lake Superior where the snow belt region of northwest Wisconsin could see a few inches Saturday night given the warm lake temperatures and very cold temps aloft. Chances for light snow linger into the work week as there remains a steady stream of low level moisture in the northwest flow through Tuesday. Highs in the teens to near 20 Sun/Mon/Tues with lows in the single digits above zero. Subzero temperatures are possible north of the Iron Range each night. Skies remain partly to mostly cloudy until Tuesday into Wednesday when a broad area of high pressure and drier air builds in from the west. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 515 PM CST Tue Nov 5 2019 VFR through the TAF period as a system skirts by to our south. Could see some shower activity Wednesday which may lead to sub-VFR conditions, but for now have left out of TAFs due to low confidence in development/timing. && .MARINE... Issued at 930 PM CST Tue Nov 5 2019 A system will pass through Iowa with largely high pressure over Lake Superior and weak pressure gradients on the western side of the lake. High pressure will build strongly Wednesday afternoon increasing the pressure gradient and thus winds and waves too. && .PRELIMINARY POINT TEMPS/POPS... DLH 13 27 13 23 / 10 10 0 0 INL 9 25 13 22 / 10 30 40 40 BRD 16 28 13 25 / 10 10 0 0 HYR 11 29 13 25 / 10 10 0 0 ASX 13 30 16 26 / 10 20 20 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ SHORT TERM...JS LONG TERM...JJM AVIATION...Wolfe MARINE...Wolfe
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
632 PM EST Tue Nov 5 2019 .AVIATION... Diminishing downstream flux of moisture off lake Michigan combined with the loss of daytime heating will leave simply a lower coverage of VFR stratus going forward this evening - mainly across FNT/MBS. A dry low level environment maintained by passing high pressure will ensure quiet/VFR conditions persist overnight and Wednesday morning. Moisture will increase along a frontal boundary expected to develop across central lower MI Wednesday afternoon and evening. Greatest impacts noted at MBS during the daylight period, with MVFR to IFR conditions likely emerging within an increasing area of light snowfall. FNT will witness a smaller window for similar restrictions during the afternoon, while PTK and the Detroit corridor initially reside outside the better moisture and favor prevailing VFR. For DTW...Clear skies across lowest 5000 ft through Wednesday morning. A lower ceiling will emerge with a limited window for brief, light rain or snow showers Wednesday afternoon. Simply highlighting this precipitation potential as prob30 - confidence in occurrence remains quite low and the result inconsequential to operations. DTW THRESHOLD PROBABILITIES... * Medium confidence for cigs to fall below 5000 ft Wednesday afternoon. * Very low confidence in the occurrence of a few light snow showers Wednesday afternoon. && .PREV DISCUSSION... Issued at 400 PM EST Tue Nov 5 2019 DISCUSSION... Dewpoints in the low to mid 20s with west winds today of 15 to 25 mph range has resulted in a wake-up call of sorts for the denizens of Southeast Michigan. Conditions have been brisk with wind chills running in the low to mid 30s. Relatively moist slab between 3.0 to 6.0 kft agl has supported overcast conditions with a flat stratocumulus deck at the top of the mixed layer. Satellite trends match up to model data suggesting that a subtle absolute vorticity center is tracking across Lake Michigan this afternoon. Will likely require this differential cva forcing to push across the area before clouds scatter out rapidly. Maintained an optimistic cloud forecast for tonight with mid-high moisture and clouds pushing into late. Some question exists on how low temperatures will go tonight, but with a mixed Given some mixed west flow, kept lows in the middle 30s. A deep reservoir of high planetary potential vorticity is in place over virtually all of northern North America this afternoon. Raob analysis from this morning captured a strong +130 knot upper level jet streak digging down the rearward face of the trough, impinging down into the northern Plains. The jet axis is forecasted to pivot to a zonal configuration by Wednesday morning. Interesting fact about upcoming setup is the wavelength of the trough is so broad that the typical subgeostrophic region to the trough base is non- existent here locally. The rocking motion to the jetstreak is expected to result in very strong and pervasive frontogenetic forcing along the 850-600mb frontal zone that will be over the northern CWA. Thus far, intra and inter model consistency has been less than ideal which has brought a considerable amount of uncertainty the Wednesday and Wednesday night precipitation forecast. The main driver for the sensible weather forecast Wednesday the magnitude of system relative isentropic ascent that will occur along the 291-296k thetae surface beginning at roughly 18Z Wednesday and continuing to around 09Z Thursday morning. The significant challenge that exists with this forecast is predicting the amount of lift/ascent that will occur along the sharp/upright midlevel frontal boundary. This is not an easy call as latest 18Z NAM run is showing more parallel system relative flow trajectories than the previous 12Z run. Just a remark on the lack of consistency. The big negative is the lack of coherent deep thermal circulation riding along the frontal boundary. The impressive aspect is the amount of system moisture that will be available as upwards of 3.0 to 4.0 g/kg will lift into far southern portions of the state by Wednesday afternoon. Additional uncertain aspects of the forecast exist, notably... a very dry antecedent airmass in the lowest 5000 ft agl and what the efficiency of snow accumulations be with models adamant at surface wet bulb temperatures reaching and exceeding the freezing mark. Do respect the cold sounding and given the 12Z model trends for QPF - long run of the RAP going at .40 liquid, did increase PoPs into the high likely for snow with total accumulations Wednesday/Wednesday night reaching 1.5 to 2.0 inches of snow. The failure point, and could be a fairly dramatic one, is if system relative flow trajectories are not orthogonal to the frontal slope that UVVs do not develop. Combination of sharp trough axis pushing directly into Southeast Michigan and convoluted jet energy lifting through the cwa will cause height rises and sharp cold front to push through the area at the end of Wednesday night. Boundary layer cold advection will kick in and result in a saturated/moist boundary layer at daybreak Thursday. The near surface environment begins will above freezing at 10Z but crashes well below freezing after 12-13Z. Deep column theta e will be shunted well to the south so no significant precipitation during that time is anticipated. Rather will be looking at some drizzle light rain showers trying to turn over to snow. Given the above freezing temperatures not expecting any signficant impacts to Thursday morning rush hour at Metro Detroit. Very strong surface high pressure will build into the state for Thursday and carry through the end of the week. Northwesterly flow will limit any prospects for lake effect snow activity into Southeast Michigan. The main narrative will be highs in the 30s with wind chills in the teens and 20s. Period of quiet weather is expected for Friday and Saturday as the upper trough departs to the east and rebounding heights encourage high pressure to build back into the Great Lakes and Ohio Valley. Seasonably cool conditions will remain in place as 850mb temps in the negative teens C will be slow to depart on Friday, but a slight improvement will be seen for Saturday and Sunday. However, chance for light snow increases by Sunday as an active polar jet streak pushes in from the Canadian prairie. This jet will force a strong cold front through by Sunday evening which brings the coldest air mass of the season thus far with 850mb temps progged to reach about -17C by late Monday. This pattern will keep a chance of snow showers and temperatures well below normal values in the forecast through the middle of next week. MARINE... Small Craft Advisories will be allowed to expire at 4 PM as winds appear on track to drop below threshold values. High pressure builds in tonight beneath a shallow ridge allowing for diminishing wave action as winds become more benign. Winds back southwesterly on Wednesday but speeds will be limited to the 10-15 knot range. A cold frontal passage Wednesday night will bring about a wind shift to the northwest prior to Thursday morning along with snow showers. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. Lake Huron...NONE. Lake St Clair...NONE. Michigan waters of Lake Erie...NONE. && $$ AVIATION.....MR DISCUSSION...CB/TF MARINE.......KK You can obtain your latest National Weather Service forecasts online at
Area Forecast Discussion
National Weather Service Wichita KS
544 PM CST Tue Nov 5 2019 .SHORT TERM...(This evening through Thursday night) Issued at 331 PM CST Tue Nov 5 2019 Quiet weather with near-normal temperatures were observed across the area today. Across the Northern Plains, a front draped across Montana, South Dakota, and Nebraska separates a much colder airmass with temperatures in the 20s and low 30s to its north. Closer to home, one important change to the forecast was the addition of chances of drizzle or light rain overnight tonight in southeast Kansas as increasing southerly flow and moisture transport with isentropic upglide increases, particularly after midnight. RAP forecast soundings depict this drizzle/light rain potential as well. As a few of the previous discussions mentioned, there remains some question about how much moisture will be advected into the region and if it will actually be enough to precipitate given the dry air above roughly 700mb in model soundings, but trends support introducing at least some POPs during the overnight/early morning hours. Thinking a lull in precipitation during the day on Wednesday is likely before more robust moisture makes its way into northern Oklahoma and southern Kansas by late Wednesday afternoon into Thursday. Agreement remains good that the focus of this system will be in the Southern Plains, but at least some rain with possible isolated thunder will be possible in south central and southeast Kansas as well. Have continued low POPs in most of central Kansas, but confidence further north in the forecast area is lower. Though temperatures appear to be warm enough to make rain the dominant precipitation type, as colder air is ushered in overnight, a brief period of a wintry mix will be possible Thursday morning. Overall, however, impacts should remain quite low with little to no accumulations expected. Northerly winds will increase behind the front as well overnight Wednesday into Thursday as the tightened pressure gradient sinks southward across the forecast area. Trended wind speeds upward slightly with this issuance to favor the CONSMOS. After complete departure of precipitation on Thursday, the main highlight will be the much cooler temperatures on Thursday, with afternoon highs reaching only into the low to mid-40s across the area, which is well below normal for the time of year. .LONG TERM...(Friday through Tuesday) Issued at 331 PM CST Tue Nov 5 2019 During the day on Friday, a front will begin approaching central Kansas, though, with very little moisture availability, things should remain dry. There remain some differences in models for this period regarding temperatures, with the ECMWF depicting more downslope flow across Kansas and therefore warmer temperatures. The GFS has been trending warmer on Friday as well, so in collaboration with surrounding WFOs, bumped up Friday`s high temperatures. Some of this southerly and downslope flow could persist into Saturday as well, so bumped these up as well over the NBM. The warmer temperatures on Friday and Saturday could come to an end as early as Sunday, however, as another trough and associated surface front moves across the forecast area. The previous forecasters have been consistently lowering high temperatures on Sunday but with a wide range of model disagreement regarding the timing of the cold front, there remains a lot of uncertainty with how warm temperatures will get. Continued to trend on the lower end of the model spread, but did not cool them as much as previous forecasts given the uncertainty. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 534 PM CST Tue Nov 5 2019 Aviation concern will be low clouds moving into southeast KS late tonight. Surface high pressure is expected to slide east tonight into Wed morning. As this occurs, south winds will allow moisture to creep north into eastern OK and eastern KS. Confidence is high that IFR ceilings will impact KCNU after 10z with some of these lower cigs potentially making it as far west as KICT by around 12z. Some drizzle will also be possible late tonight at KCNU. The other story will be a strong cold front to move through Wed afternoon through Wed evening, flipping winds around to the north. Front will make it to KRSL around 19z and KICT closer to 00z Thu. Some lower ceilings will be possible a few hours after the front moves through as the colder air spills south. && .FIRE WEATHER... Issued at 331 PM CST Tue Nov 5 2019 Although red flag warning criteria and critical fire danger are unlikely over the next several days, an influx of dry air on Friday may produce very high grassland fire danger in a couple of central Kansas counties. Otherwise, intermittent high grassland fire danger is expected over the next week or so. && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 43 65 31 43 / 10 40 70 10 Hutchinson 40 64 28 42 / 0 30 50 10 Newton 42 63 28 41 / 0 40 60 10 ElDorado 43 64 31 42 / 10 50 70 10 Winfield-KWLD 45 65 33 43 / 20 50 80 20 Russell 37 62 24 41 / 0 10 10 0 Great Bend 37 64 24 41 / 0 10 20 0 Salina 39 63 26 41 / 0 10 30 0 McPherson 39 64 26 41 / 0 30 40 10 Coffeyville 46 62 36 44 / 30 70 90 40 Chanute 43 62 33 43 / 20 60 80 20 Iola 43 62 33 42 / 20 60 80 20 Parsons-KPPF 45 62 35 43 / 30 70 90 30 && .ICT WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...TAV LONG TERM...TAV AVIATION...RBL FIRE WEATHER...TAV
Area Forecast Discussion
National Weather Service Phoenix AZ
509 PM MST Tue Nov 5 2019 .UPDATE...Updated Aviation Discussion. && .SYNOPSIS... Above normal high temperatures with dry conditions are expected through most of the week. The one exception will be very late tonight and Wednesday when a weak weather system will bring slight chances for isolated showers and thunderstorms mainly north and east of Phoenix. High temperatures across the lower desert will be in the mid to upper 80s, with lows in the mid 50s to lower 60s through next weekend. && .DISCUSSION... Strong high pressure aloft is bringing another rather warm day (for early November) across the region, with most lower desert locations seeing temperatures well up in the 80`s at this hour, under mostly clear skies. A weak low off the southern California and Baja coast, easily discernible on water vapor imagery, is still expected to provide a modest increase in moisture in the Southwest the next few days. Surface dew points will increase from the current low 30s into the upper 40s by Wednesday night while PWAT values also increase close to 0.75 inches. That mark nears the 90th percentile for the date according to the SPC sounding climatology. Latest high-res model output continues to show the main upper low lifting northeastward over extreme northern Baja tonight, then across AZ on Wednesday. The combination of moisture and weak dynamics is expected to produce isolated-scattered showers and thunderstorms across the region very late tonight and on Wednesday. Although the best chances for showers/TS will be over the higher terrain north and east of Phoenix, a few showers cannot be ruled out over SW AZ late tonight and over the lower deserts of south-central AZ during the day on Wednesday as the cold core of the upper low helps to destabilize the air mass, as depicted on the latest HRRR runs. Although most of the SREF plumes do show a few hundreds of an inch of rainfall for Phoenix, given the spotty nature of the rainfall, it is likely that most locations will see no rain at all (mainly just virga), with a few lucky spots receiving 0.10-0.20 of a inch. The presence of these showers and an increase in cloudiness should push highs down a bit across south-central AZ on Wednesday, keeping them down in the mid-80`s. Modest instability (a couple of hundred joules of CAPE) could also help to trigger an isolated thunderstorm or two as well. After the low moves eastward, the relatively persistent ridge will restrengthen over the west coast. H5 height levels recover quickly and rise through the weekend slightly above 580 dm. Combined with generally sunny skies, temperatures will remain above seasonal normal values near the mid 80s through the beginning of next week. && .AVIATION...Updated at 0009Z. South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: Limited aviation concerns expected over the next 24 hours with winds remaining light and at times variable. An approaching weather system will continue to support increasing mid and upper level cloud coverage across south-central Arizona with broken cigs aoa 10 kft developing around 10Z. Could see some virga Wednesday morning while chances for a light shower increase late morning into the early afternoon. Have added VCSH to all the TAFs, but can`t completely rule out the possibility for an isolated thunderstorm. However, the best chance for an isolated thunderstorm will remain over areas north and east of Phoenix. Cigs begin to scatter out tomorrow afternoon with scattered decks remaining around 10 kft. Southeast California/Southwest Arizona including KIPL and KBLH: Few aviation concerns expected over the next 24 hours. An approaching weather system will allow for an increase in mid and upper level cloud cover with decks developing around 10 kft overnight. Winds will remain light becoming variable at times through the period. Aviation Discussion not updated for amended TAFs. && .FIRE WEATHER... Friday through Tuesday: Drier and warmer than normal conditions will be the rule over the region on Thursday into early next week as the Desert Southwest remains under the influence of high pressure or northwest flow aloft. Minimum relative humidity values will stay above 20 percent across south central Arizona on Friday before falling into the teens for the weekend through early next week. Over southwest Arizona and southeast California, relative humidity values will dip into the teens each day with single digit values possible at some locations early next week. Light diurnal winds should persist through the forecast period. && .SPOTTER INFORMATION STATEMENT... Spotters should follow standard reporting procedures. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ DISCUSSION...Deems/Percha AVIATION...Smith FIRE WEATHER...CB/Percha
National Weather Service Raleigh NC
1001 PM EST Tue Nov 5 2019 .SYNOPSIS... A dry cold front will move across the area tonight. High pressure will settle into the Mid Atlantic on Wednesday before sliding east off the DELMARVA Peninsula later Thursday. A stronger cold front will slide east through the region Thursday night and Friday morning, allowing even colder high pressure to fill into place. && .NEAR TERM /THROUGH TONIGHT/... As of 955 PM Tuesday... A dry cold front will move across the area tonight. The bulk of the cloud cover ahead of the front is shifting to the east of the area this evening. The latest HRRR continues to show the potential for some fog to developing this evening into the overnight ahead of the front across the Coastal Plain of central NC (generally around the I- 95 corridor and to the east). Will need to monitor visbys, but do not plan to issue a DFA at this time. The cold front should move through eastern/southern portions of the area by around 5 AM or so, ending any fog threat. Low temps will be driven by CAA, with lows ranging from the lower 40s NW to the lower 50s SE. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... As of 200 PM Tuesday... By Wednesday, the CAA regiment will continue, with northerly to northeasterly winds increasing to the 6 to 10kt range shortly after sunrise. Mostly clear skies under high pressure should allow for a typical diurnal temperature curve, only limited in magnitude by the cP airmass features in place with plentiful surface subsidence. Afternoon highs will settle in the low (north) to upper (south) 60s. Overnight lows will be comparable to Wednesday morning temperatures, bottoming out in the upper 30s to low 40s with good radiational cooling conditions present. && .LONG TERM /THURSDAY THROUGH TUESDAY/... As of 150 PM Tuesday... The 12Z NAM was not considered as heavily with the late week system due to initialization errors and not receiving all 12Z upper air balloon data. An upper trough axis and surface cold front will approach the state on Thursday. There is only a slight chance that rain showers will receive the Triad before sunset, nearly all rain will occur overnight. Still not impressed with the overall dynamics of the storm, and have stuck with low likely pops on Thursday night. The system does appear to be more progressive than it did yesterday, so have decreased pops Friday morning across the east and eliminated them for Friday afternoon. Colder air moving into the region may not be as noticeable Thursday night, but certainly will be by Friday, with many locations struggling to reach 50 degrees on Friday or Saturday. Friday night should see all locations dropping below freezing, with similar warmer temps Saturday night. High pressure will move into the region Friday into Saturday, with a dry frontal passage expected on Sunday considering there will be a lack of moisture along the front. Monday and Monday night another upper level trough will pass over the region. The GFS is much drier than it was yesterday, with the ECMWF showing just a glancing blow of precipitation. Have gone with just slight chance pops from Raleigh to the north and east. While there will be some temperature recovery Sunday and Monday, with most locations returning to the 60s, highs will drop back into the 40s once again on Tuesday. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... As of 635 PM Tuesday... 24 hour TAF period: Fairly high confidence VFR conditions will prevail through much of the TAF period, however there is a chance a brief period of sub-VFR cigs/visbys could occur across eastern terminals ahead of the front. Otherwise, just some scattered to broken cigs around 4 kft are expected overnight at KRDU, KFAY and KRWI. Winds will be calm to light and variable overnight, becoming a bit strong in the east for a few hours in the morning/early afternoon. -KC Looking ahead: A cold front will approach the region late Thursday and Friday providing the next chance of sub-VFR conditions, primarily in the form of lowering CIGs/VSBYs associated with rain showers. Cooler, drier, and quieter high pressure settles in for the remainder of the weekend. -JJM && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...BSD/JJM NEAR TERM...BSD SHORT TERM...JJM LONG TERM...Green AVIATION...KC/JJM
Area Forecast Discussion
National Weather Service Topeka KS
537 PM CST Tue Nov 5 2019 ...AVIATION UPDATE... .SHORT TERM...(This evening through Wednesday night) Issued at 308 PM CST Tue Nov 5 2019 Water vapor imagery at 1930Z shows an upper low situated over Ontario with broad troughing across much of the northern CONUS associated with this low. Extending from that feature, a weaker circulation is noted approaching the Baja region of Mexico with a ridge off the Pacific coast. Surface high pressure sits to our east over the Upper Midwest while weak low pressure is developing in the eastern Rockies. We have some high clouds in northeast KS near the NE border, and we should continue to see mostly clear skies and light winds this evening and overnight as the surface high pushes east. WAA will begin to develop overnight, which should keep lows a bit warmer in the upper 30s to low 40s. In east central and southeast KS, we are likely to see a surge of low-level moisture from the south, which could bring some drizzle for a brief period early tomorrow morning in the southeastern CWA. Depending how much moisture moves in and how widespread it becomes, could see some patchy fog or low stratus as well, but at this time have just brought in slight chance PoPs southeast of I-35 to account for drizzle. Heading into Wednesday morning, a cold front approaches the KS/NE border and we`ll continue to see WAA ahead of the boundary before it pushes south through the afternoon and evening. The surface front should be entirely south of the CWA by midnight Thursday while the 850mb front will take a bit longer, likely not getting south of the area until early Thursday morning. The overall best forcing and highest chances of precip look to be trending south of our area, and moisture isn`t overly impressive Wednesday evening into early Thursday. East central KS has the best chance of seeing anything, and NAM forecast soundings best support drizzle as temperature profiles stay mostly above freezing. It`s worth noting there is a cold layer in the low levels that gets below freezing after midnight, but surface temps remain above freezing. Saturation only occurs from 800-925mb and we already show signs of drying as we get closer to sunrise. That being said, thinking drizzle is the most likely precip type with only a very small opportunity to see any freezing drizzle if we cool to the wet-bulb temperature. RAP soundings stay above freezing through the entire period, which further supports the theory for drizzle. Highs Wednesday will reach the low to mid 60s ahead of the front, cooler in the 50s near the KS/NE border, with lows falling back to the mid 20s to low 30s Wednesday night. .LONG TERM...(Thursday through Tuesday) Issued at 308 PM CST Tue Nov 5 2019 Transitioning into the extended period, any lingering drizzle and/or snow flurries will come to an end early Thursday morning across east- central KS. Otherwise, surface ridging will build into the area through the Thursday, yielding mostly sunny skies and light winds for the area. The light winds and clear skies will set the stage for a cold morning Friday with lows in the lower 20s. A weak cold will approach the area Friday into Friday night as a weak midlevel shortwave trough translates through the northwest flow. Little in the way of CAA is anticipated given the weak nature of the midlevel shortwave. A nice warmup is expected for Saturday, ahead of the next cold front, as southwesterly to westerly winds usher in warmer temperatures. Afternoon highs Saturday are expected to reach the low to perhaps middle 60s. The aforementioned secondary cold front will push through the CWA late Saturday night into early Sunday. As a result, much cooler temperatures are expected for Sunday with daytime highs in the 40s. Continued CAA into Sunday night and Monday will result in well-below normal temperatures with lows in the 10s/20s and highs in the 30s. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1134 AM CST Tue Nov 5 2019 Light SE winds will continue this afternoon/evening with mostly clear skies. By tomorrow morning, models hint at a surge of moisture from SE KS potentially bringing in fog or low stratus, but confidence remains low on this reaching TOP/FOE. Could see MVFR/IFR cigs or vsby if this occurs, otherwise VFR conditions should continue for the period. && .AVIATION...(For the 00Z TAFS through 00Z Thursday) Issued at 537 PM CST Tue Nov 5 2019 There is good agreement among the models in a slug of low level moisture advecting into east central KS by Wed morning. The main uncertainty is how far north this moisture may get. With the RAP/NAM/GFS forecast soundings saturating low levels at TOP and FOE for a few hours, have introduced some MVFR CIGS. Although the moisture advection could be low enough that the stratus comes in below 1000 FT. Confidence is only about average as much of the objective guidance keeps the CIGS just to the southeast of TOP and FOE. It may not be out of the question that an advection fog develops given dewpoints in the lower and mid 40s are progged to move north overnight. So will monitor trends and adjust accordingly. Thanks for the coordination EAX. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Picha LONG TERM...Baerg AVIATION...Wolters