Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/05/16


Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1152 PM EDT Fri Nov 4 2016 .AVIATION... Analysis of evening observations and model data indicate a somewhat reduced potential for low clouds and fog during the night in the MBS to FNT region compared to earlier expectations. Westerly flow around the north flank of the Ohio Valley surface high will continue to carry increased low level moisture over Lake Michigan and into lower Michigan, but this air is also warmer from the surface to 900 mb and less favorable for cloud development. Evening satellite imagery illustrates the temperature contrast where low clouds remain over southern Ontario and eastern Lake Erie/Ontario while conditions are cloud free over the western Great Lakes. It is likely that the warmer air moving in from the west will take longer to produce clouds over Lake Michigan and Lower Michigan leading to less coverage or shorter duration over the SE Michigan terminal corridor. Those that are able to form will then steadily mix out during the morning and leave VFR under high clouds by afternoon through Saturday evening. FOR DTW... Shallow MVFR fog remains possible for a few hours around sunrise with an outside chance of brief entry level IFR before the wind increases slightly. Observational evidence indicates best potential for stratus staying north of DTW through the morning. //DTW Threshold Probabilities... * none. && .PREV DISCUSSION... Issued at 311 PM EDT Fri Nov 4 2016 DISCUSSION... A dry and seasonably warm environment will mark conditions through the upcoming weekend. Moderating thermal profile prompted by a steady increase in upper heights through this period, the local area immediately downstream of an elongating upper ridge slowly building toward the Great Lakes. Deeper column warm air advection ramps up tonight and Saturday as the flow backs to westerly, allowing for a steady exit of the residual low level thermal trough. High pressure anchoring across the Ohio Valley will then introduce a light southwest low level gradient. 925 mb temperatures by Saturday afternoon roughly 10 degrees warmer than readings noted today /10- 11C/. This profile will support afternoon highs reaching into the lower 60s. There is the potential for a fog/very low stratus component to emerge late tonight, which could subsequently provide an early day disruption to the diurnal temperature response. Dense fog formation this past night across WI/IL centered near the surface high. Downstream advection of this moisture will commence tonight within backing flow, with higher resolution model guidance (HRRR, RAP & 4km NAM) displaying very low surface condensation pressure deficits with saturated near surface conditions per sounding data by 09z-12z. A high degree of uncertainty here, with the maintenance of a light SW gradient north of the high perhaps maintaining just enough mixing to mitigate a larger fog issue. Will simply provide an introductory patchy fog mention at this stage. High pressure eases northward into the region by Sunday as the upper ridge axis enters the western Great Lakes. Existing air mass similar to that noted Saturday /maybe a touch warmer/, so highs of low-mid 60s attainable under a high degree of insolation. More favorable positioning of the high nearby may provide a greater opportunity for fog development late Saturday night/Sunday morning. Surface high pressure and an amplified upper-level ridge will continue to push east across the eastern half of the U.S., bringing another round of dry conditions to the region. Temperature highs will continue to sit steady in the lower 60s as light S/SW winds advect warmer air into the region. The next chance for precipitation will come Tuesday night into Wednesday morning as an upper-level disturbance moves through, however, with weak forcing and dry low- level conditions, we`re leaving the PoPs low. Otherwise, high pressure will continue to be the main story for the week, leaving us relatively dry through the better part of the week. MARINE... Northwest winds of 10 to 15 knots will back to the west-southwest this evening and increase to 20 knots or so over Lake Huron as the pressure gradient tightens for a short time between high pressure over the Ohio Valley and a shortwave trough passing just north of the Great Lakes. Wind gusts will approach 25 knots, especially from 03z-09z. The most persistent gusts will exist where wind funnels up Saginaw Bay and also through the Straits. Winds will gradually weaken and become light and variable Sunday as a warmer airmass works into the area. Light southerly winds will then develop on Monday as this high settles southeast of the region. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. Lake Huron...Small Craft Advisory until 8 AM EDT Saturday FOR LHZ421-441. Lake St Clair...NONE. Michigan waters of Lake Erie...NONE. && $$ AVIATION.....BT DISCUSSION...MR/AM MARINE.......DG You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.
Area Forecast Discussion
National Weather Service Northern Indiana
731 PM EDT Fri Nov 4 2016 .SYNOPSIS... Issued at 252 PM EDT Fri Nov 4 2016 High pressure over northern Illinois will move slowly southeast to the Ohio Valley tonight, and then to the eastern seaboard on Monday. This will provide fair weather across the area through early next week. Lows tonight in the upper 30s and lower 40s. Temperatures will warm a bit over the weekend with highs in 60s and lows in the 40s expected. && .SHORT TERM...(This Evening through Saturday) Issued at 252 PM EDT Fri Nov 4 2016 Main focus of short term will be potential for stratus/fog development. Stratus decks at or below 2000 ft have been slow to erode across portions of northern Ohio as well as eastern Iowa/NW Illinois/SW Wisconsin on the periphery of sfc high pressure centered over N Illinois. The center will drift slowly south through the period with trajectories of trapped low level moisture seeming to push the moisture currently NW of the area into portions of Lower Michigan with Ohio moisture dropping south. HRRR appears to laugh at this scenario bringing in stratus into NW areas overnight. Given crossover temperatures will be in the middle to upper 30s in many locations and forecasted lows will be at least a few degrees warmer as well as winds around 5 knots suggests fog potential may be quite limited. Will have a few clouds in the grids but at this point think mostly clear to clear skies should prevail. Dry conditions will prevail into Saturday with mostly sunny to sunny skies and highs reaching into the lower to middle 60s. && .LONG TERM...(Saturday Night through Friday) Issued at 252 PM EDT Fri Nov 4 2016 Conditions will not feel anything like early November normally would with all signs still pointing towards above to much above normal temperatures for the area and limited chances for rainfall. Upper level ridge will move into the area over the weekend with 582 dm heights edging north by Sunday evening. Mixing will take place through at least 925 mb and possibly 900 mb yielding afternoon highs Sat through Monday well into the 60s and possibly a few 70s southern third or so. Northern stream energy will try to force a front south into the region Tuesday with ECMWF/GFS varying on handling. Will continue with dry forecast for the time being. Ridging will build back in with heights of 579 to 582 in place once again. Decreasing sun angle will keep full mixing from taking place with highs in the low to middle 60s. Towards the end of the period, models show a somewhat more significant trough trying to move into the Great Lakes with large differences in scenarios (both for temperature and precip). Will hold dry forecast. && .AVIATION...(For the 00Z TAFS through 00Z Saturday Evening) Issued at 729 PM EDT Fri Nov 4 2016 Continued VFR conditions through the forecast period. Isolated ground fog is possible in some of the more sheltered and low lying areas. Do not expect to have this affect the TAF sites. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...JT/NG SHORT TERM...Fisher LONG TERM...Fisher AVIATION...Lewis Visit us at www.weather.gov/iwx Follow us on Facebook...Twitter...and YouTube at: www.facebook.com/NWSNorthernIndiana www.twitter.com/nwsiwx www.youtube.com/NWSNorthernIndiana
Area Forecast Discussion
National Weather Service Lubbock TX
927 PM CDT Fri Nov 4 2016 .UPDATE... Forecast overnight into the day Saturday looks to remain on track. Low cloud development is underway across the southern South Plains and Rolling Plains as easterly flow above the surface increases and advects higher dewpoint air into the region. Meanwhile water vapor shows a shortwave trough lifting northeast around the ejecting upper low over eastern AZ. Lift associated with this wave is creating scattered showers and storms from the foothills of the Sangre de Cristos to north of El Paso. This activity is expected to remain west of the Texas state line overnight. The latest short range models are indicating however some light QPF across the Rolling Plains and portion of the South Plains after midnight. Feel this will mostly be realized as areas of drizzle as deep isentropic ascent occurs in the absence of instability. Areas of fog will also be more common as higher level clouds associated with earlier shortwave exit into OK and north TX and light easterly surface winds advect upper 50 dews into the Rolling Plains. Very low clouds, fog and drizzle are expected to start the daylight hours Saturday and be slow to give way to improving conditions as the afternoon begins. This should limit instability and keep thunderstorm chances very low. && .PREV DISCUSSION... /issued 631 PM CDT Fri Nov 4 2016/ AVIATION... Rapidly deteriorating flying conditions expected later this evening as southeasterly winds above the surface strengthen and advect higher dewpoint air northwestward into the region. Only real uncertainty is with onset of stratus so have kept previous timing around 06Z which is consistent with latest short range models. Cloud cover will lower with time as diurnal cooling and moistening takes place with fairly widespread visibility restrictions by daybreak. Areas of drizzle brought about by deep isentropic lift will add to the cause. LIFR conditions forecast at all TAF sites through the morning with slight improvement in ceilings during the afternoon. PREV DISCUSSION... /issued 334 PM CDT Fri Nov 4 2016/ SHORT TERM... Nicely stacked cyclone was creeping ENE across SE Arizona early this afternoon upstream of an upper ridge axis poised over the middle of the Lone Star State. A weak trough was attempting to erode this trough, but so far ascent and low level saturation have been lackluster with this wave. Worse, visible satellite shows clear skies already expanding into our western zones in the wake of this wave and its shield of high clouds. This clearing is likely to be consumed by thick stratus tonight as widespread upslope/easterly winds transport richer mixing ratios westward. Model soundings support this otherwise ideal pattern of widespread stratus and even saturate the column deep enough for drizzle at times. This drizzle could quell the dense fog potential, but RAP, HRRR and MOS indicate otherwise. Background ascent looks to remain very muted on Saturday over all but our far western tiers of counties. Lift there will be aided by a zone of weakening upper diffluence ahead of the cyclone lifting NE across the Four Corners. Slight uptick in isentropic ascent could garner some convective showers near the NM state line, but profiles are looking less and less promising for any thunder with surface and elevated CAPE largely absent for much of the day. Farther east, the bases of very low stratus may rise just enough through the day to allow for some reprieve from drizzle, but max temps continue to trend lower toward the coolest guidance given minimal insolation. LONG TERM... Showers and thunderstorms remain in the forecast late Saturday into Sunday as a relatively weak trough lags behind the center of an upper low interacting with the northern jet across the Rockies and into the northern Plains. As the trough axis shifts east of our longitude we will see a narrow swath of drier air briefly fill in from the Texas/New Mexico border east through the South Plains to the edge of the Caprock. Another closed low splits from amplifying ridge across Canada and begins to shift due south out of the central Rockies toward West Texas on Monday. Surface pressure falls across a cold front pushing south out of the Texas Panhandle through the South Plains early Tuesday will increase chances for more widespread light rainfall Tuesday and Wednesday. Rain chances continue through the end of next week as the upper low stalls to our west. Not much confidence in details beyond the middle of next week until we see how the strongly amplified ridge to our north begins to break down. Overall the model guidance is in good agreement with the evolution of the low tracking south out of the Rockies and parking to our west. After a warm October and beginning of November we we will see plenty of clouds and precipitation chances to help drop temperatures below normal values over the next week or so with Monday near 70 in our brief window of drier air. Otherwise we`ll see highs in the low to mid 60s and overnight lows gradually cooling from 50s this weekend into the low 40s by the end of the week. && .LUB WATCHES/WARNINGS/ADVISORIES... None. && $$ 24
Area Forecast Discussion
National Weather Service Norman OK
954 PM CDT Fri Nov 4 2016 .UPDATE... Updated temperature/dew point/wind forecast. && .DISCUSSION... Dew points have remained anomalously high across central/southern Oklahoma and western north Texas, so opted to increase them based on trends. However, light east to northeast winds should result in some drier air to slowly advect eastward across parts of central Oklahoma tonight. Temperatures were also increased based on the increased moisture/cloud cover. The HRRR/HRRRX indicates low stratus and/or fog will continue/expand primarily across western Oklahoma and parts of western north Texas. A weak QPF signal on the HRRR/RAP/NAM also suggests some drizzle is possible. Based on the weak upslope/easterly flow that is coincident with some moisture advection, this seems reasonable. Mahale && .PREV DISCUSSION... /issued 625 PM CDT Fri Nov 4 2016/ DISCUSSION... AVIATION... Low clouds are expected to redevelop across western Oklahoma and adjacent parts of Texas tonight. IFR ceilings will form and some places will have fog as well. Clouds will stay low over western Oklahoma most of Saturday with light upslope winds. PREV DISCUSSION... /issued 224 PM CDT Fri Nov 4 2016/ DISCUSSION... Overcast conditions have prevailed across mainly southern portions of the area. Winds will gradually veer to southeasterly this evening and overnight resulting in moisture moving into northwest Oklahoma which may lead to fog there. Further southwest across southwest Oklahoma and portions of western north Texas, visibility is already slightly reduced and stratus is more extensive. Visibility may fall as we cool tonight but the better chance of fog seems to be further northwest where cooling initially this evening may a little quicker (drier boundary layer and only modest cirrus coverage). RAP forecast soundings suggest enough depth to the saturated layer for some drizzle, as was observed across potions of the area this morning. Have highlighted the most likely areas for patchy drizzle later tonight through the morning based on latest short term model data, but spatial adjustments may be needed based on trends. A cut off low will gradually move northeast and accelerate as it opens this weaken. The time period for maximum forcing for ascent and moisture advection that will lead to the highest precipitation probabilities will be late Sunday through early Monday. Have deemphasized thunder in the public forecast by limited thunderstorms to slight chance during this period given lack of instability seen in model forecast soundings. Starting the beginning of next week and into the middle of next week, typical uncertainties arise. Deterministic output is similar in the overall pattern of departing wave to our east and a south/southwest moving increasingly closed upper low to our west. The individual GFS ensemble members show a myriad of possibilities with how this will evolve and consequently where any areas of noteworthy ascent are positioned. Until confidence increases, probabilities will be limited to low-mid range chance and spread across several days. Adjustments to model blends were minimal for this forecast issuance. Temperatures should be close to normal through the forecast period. BRB && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 55 68 50 69 / 0 0 0 30 Hobart OK 58 65 53 65 / 10 10 10 50 Wichita Falls TX 59 68 53 67 / 10 10 10 60 Gage OK 49 65 50 66 / 0 10 30 50 Ponca City OK 50 70 48 70 / 0 0 0 10 Durant OK 55 71 49 70 / 0 0 10 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ 10/09
Area Forecast Discussion
National Weather Service Tucson AZ
835 PM MST Fri Nov 4 2016 .SYNOPSIS...A few showers may occur across the White Mountains Saturday morning. Otherwise, dry conditions will prevail into early next week. The next low pressure system may bring some showers to eastern areas around mid week. Daytime highs will be near or slightly above seasonal averages, with seasonably cool overnight low temperatures. && .DISCUSSION...A weakening low pressure system aloft was centered over northeast AZ this evening. Clear skies prevailed across southeast AZ at this time, except for some cirriform clouds mostly near the International border south-to-southeast of Tucson. Temps at lower elevations valid 8 PM MST had cooled into the mid 50s-mid 60s, and winds were light wly/nwly at less than 10 mph. The upper low will continue to fill while drifting toward the Four Corners region tonight, then will become an open-wave system with the mid-level trough axis Saturday afternoon extending from western Colorado southward into far southeast AZ. 05/00Z NAM suggests that measurable rain may occur mainly across the White Mountains Saturday morning with precip-free conditions elsewhere. The official forecast was updated earlier this evening with this scenario in mind. Thus, dry conditions will prevail the rest of tonight, and a slight chance of showers exists across the White Mountains Saturday morning. Otherwise, dry conditions elsewhere Saturday with the sky condition ranging from clear to partly cloudy. High temps Saturday will be nearly identical to temps achieved this afternoon across eastern sections, but will be a few degs warmer from Tucson westward into western Pima County and south-central Pinal County. Please refer to the additional sections for further detail. && .AVIATION...Valid through 06/06Z. There is a slight chance of -SHRA mainly across the White Mountains northeast of KSAD Saturday morning. Otherwise, SKC especially west of KTUS, and a FEW clouds around 8k-12k ft AGL with FEW-SCT clouds above 20k ft AGL elsewhere into Saturday evening. Surface wind variable in direction less than 12 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Dry conditions into Monday except for a few showers across the White Mountains Saturday morning. The next low pressure system will then bring a slight chance of showers east of Tucson around the middle of next week. 20-foot winds through Monday will be terrain driven less than 15 mph, then gusty east winds should occur by Wednesday due to the influence of the low pressure system. && .PREV DISCUSSION /257 PM MST/...The low has lifted just north of our area near the central Arizona border with New Mexico. A partial clearing trend with some cumulus popping up on recirculated boundary layer moisture. Greenlee county will still be going for a few more hours, but most of the activity will be north and east of our area. Patchy fog possible in eastern areas Saturday morning. The latest HRRR shows diminishing dew point trends, and along with the partial clearing, a few spots will drop a degree or two lower tonight. Tonight and Saturday night we will see chilly seasonal temperatures with coldest isolated eastern valley locations in Cochise county dropping into the middle to upper 30s. Daytime highs will climb a few degrees as a shortwave ridge phases across the area from the west over the weekend, but not far from seasonal averages for early November. However, the main strength of the ridge will probably stay west of our area with impulses sagging back into the front of the ridge and into New Mexico. Some easterly spill-over from that could bring a few showers to eastern areas the second half of the new week. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Francis/Meyer Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Area Forecast Discussion
National Weather Service Lincoln IL
234 AM CDT Sat Nov 5 2016 .SHORT TERM...(Today and tonight) ISSUED AT 232 AM CDT Sat Nov 5 2016 Main concern initially is the extent of fog early this morning. RAP soundings in Bufkit indicate we could spike down with some locally dense fog again around sunrise in many locations of central and southeast Illinois. Hydrolapse plots show increasing moisture with height in the lowest layer of the air mass, which is one primary indicator of fog formation. HRRR and RAP visibility forecasts are focusing fog west of Decatur to Bloomington and south of Peoria to Canton. Therefore, have expanded fog into a majority of the forecast area for the first couple of hours of the morning. Not confident enough to issue a dense fog advisory at this point due to uncertainty on coverage, but will monitor closely as the night progresses. High surface pressure will dominate the remainder of the short term forecast, with mostly sunny skies today and mostly clear skies tonight. Light fog will be possible again late Saturday night due to little change in air mass, and have included patchy fog in many areas again. High temperatures today look to climb above normal, with the help of southerly winds and nearly full sunshine. Guidance numbers were generally followed with highs expected to reach the upper 60s west of I-55 and the mid 60s east of I-55. Lows tonight should bottom out in the lower 40s, based on expected lowest afternoon dewpoints. && .LONG TERM...(Sunday through Friday) ISSUED AT 232 AM CDT Sat Nov 5 2016 Main theme for next week continues to be with temperatures remaining well above normal for early November. While the GFS and ECMWF have some significant differences with the Tuesday wave, both keep the colder air over Canada. By late in the week, a pattern change starts to set up, with a slug of colder air dropping into the Great Lakes. Will watch this for the upcoming forecast cycles as this is largely beyond the current forecast range, but current indications are that it would be short lived. Regarding the wave in question, the latest models are in reasonable agreement through Monday evening, with the wave extending across the eastern Dakotas to along the Manitoba/Ontario border. However, the latest ECMWF breaks off a piece of energy along the southern part of the wave early Tuesday, and drops it southwest into Texas by Thursday morning. This is a significant shift from the morning run and rather suspect at the moment, so went with a blend of the current GFS and the old ECMWF instead. With the greater lift near the Great Lakes, have kept PoP`s in the slight chance range for Tuesday and Tuesday night. The late week short wave passage currently appears dry. && .AVIATION...(For the 06Z TAFS through 06Z Saturday night) Issued at 1110 PM CDT Fri Nov 4 2016 Some patchy fog with MVFR vsbys still possible in the 09z-13z time frame, otherwise VFR conditions will prevail for the remainder of the forecast period. High pressure centered over east central Illinois will drift slowly away from the area through Saturday. A band of cirrus clouds was tracking east out of west central Missouri and will push into west central Illinois by morning, otherwise a mostly clear sky is expected overnight. Forecast soundings indicate the most favorable moisture profile in the low levels will be near SPI by dawn Saturday with the current dew point spreads the lowest in that area this hour as well. Not entirely convinced the remainder of our forecast sites won`t see any shallow ground fog form towards dawn, but the fact that the low levels of the atmosphere mixed out well this afternoon and some high level clouds were expected to push into west central through central Illinois by morning should keep any development patchy at best and not as dense as what we saw in parts of our forecast area Friday morning. Light and variable winds tonight will become southwest at less than 10 kts on Saturday. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Shimon LONG TERM...Geelhart AVIATION...Smith
Area Forecast Discussion
National Weather Service Morristown TN
341 AM EDT Sat Nov 5 2016 .SHORT TERM (Today and Tonight)... A much cooler start to the morning than just 24 hours ago. A wide range of temperatures at 3 am generally ranging from the upper 30s to the mid 50s. These values are still above normal for early November but much cooler than yesterday morning. Expect there could be a few isolated areas of frost in the cooler portions of SW VA and NE TN but do not anticipate anything widespread. Current water vapor imagery and RAP upper air analysis indicates a ridge across much of the Central U.S. with a trough just off the Atlantic Coast. PW values remain in the 0.3-0.4 inch range throughout the short-term forecast with sunny skies expected today. Upper level heights will continue to increase today as the ridge builds in from the southeast. With plenty of insolation and continued dry conditions, went towards the higher side of guidance with highs today in the upper 60s to low 70s for most valley locations. Ideal radiational cooling conditions will setup once again tonight with clear skies, light winds, and high pressure. However, expect lows will be similar to slightly warmer than this morning with lows in the mid 30s to upper 40s. Again, any frost tonight should be isolated and limited to SW VA and NE TN. .LONG TERM (Sunday through Friday)... Little change in the weather pattern early in the extended with a strong ridge of high pressure remaining in control. This will maintain the dry and unseasonably warm conditions. Highs will continue to climb into the upper 60s to mid 70s range with relative humidities lowering to 35 to maybe around 25 percent Sunday through Tuesday. This will continue to impact the fire danger potential. Through the rest of the extended... confidence quite low. Current run of the GFS has quickened the arrival of an approaching weak cold front...bringing it into the region Tuesday night into Wednesday. The ECMWF maintains and a slower movement of Thursday night into Friday. The strength and amount of associated precip also remains in question. For now... will keep pops on the low side...generally 20 to 30...and go with the more consistent slower timing. However...may begin trending faster with the system based on future model runs. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 74 47 74 45 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 72 43 71 43 / 0 0 0 0 Oak Ridge, TN 72 43 71 43 / 0 0 0 0 Tri Cities Airport, TN 66 36 68 40 / 0 0 0 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...None. TN...None. VA...None. && $$ MA/MJB
Area Forecast Discussion
National Weather Service Denver/Boulder CO
950 AM MDT Sat Nov 5 2016 .UPDATE... Issued at 930 AM MDT Sat Nov 5 2016 Upper low near the four corners with weak mid level qg ascent over southwest and south central CO. HRRR runs have been generating some pcpn over Lincoln County late this morning and aftn as pcpn shifts gradually northward. The pcpn decreases as it advects northward so will confine the mention of pops to zones 41..46 and 47 for now. Some adjustment to slightly less cloud cover as well over the northern tier counties this morning...otherwise the rest of the grids appear to be on track. && .SHORT TERM...(Today and tonight) Issued at 314 AM MDT Sat Nov 5 2016 An upper level low near the Four Corner will continue to slowly lift north-northeast today and tonight as it weakens. Mid and upper level moisture will increase through out the day. This is expected to bring scattered showers to the mountains, with the best chance south. For the Front Range and eastern plains, the low levels look too dry for precipitation today. The airmass will remain warm with the snow level in the mountains being 10000 to 11000 feet. High temperatures will be cooler today due to the increased cloud cover but still well above normal for this time of year. Scattered mountains showers will continue into the evening and decrease overnight. Not a lot of moisture makes it into the northern half of Colorado. Looking at light snow amounts for the mountains with a few locations seeing up to 2 inches. Low level moisture will increase over far eastern Colorado. This will likely lead to low clouds. There is just a slight chance for rain with this. If any occurs it will be very light. .LONG TERM...(Sunday through Friday) Issued at 314 AM MDT Sat Nov 5 2016 An open shortwave trough is progged to make its way across Colorado on Sunday bringing scattered light rain/snow showers to parts of the high country and gusty nwly winds to the Front Range and adjacent high plains. Winds appear to strengthen some through the day with increasing subsidence displacing downward momentum aloft on the back side of the trough. Speeds not expected to reach high wind criteria but we could see speeds in the 30-50 mph range on the mtn ridges and foothills. By evening...winds should subside and the high country showers should come to an end with drying aloft. Clearing skies and light breezes overnight will lead to another night of chilly temperatures but readings by morning still warmer than normal for the date. By Monday...the upper trough moves east as the mean upper ridge regains its strength over the Great Basin. A powerful Pacific jet stream crossing the northern Pacific Ocean roughly between 40-60 deg latitude...will continue to buckle and produce large quasi- stationary mid-latitude troughs off the west coast of North America according to the models. This will help to re-establish the upper ridge over the western CONUS consequently steering moisture bearing maritime storms well to our north and preventing any major intrusions of arctic air from Canada. However...models still show a weak cold front advancing down the front side of this upper ridge and into northeast Colorado on Monday. Could see a 4-8 deg f cool down as well as some cloud cover with its passage. Overnight clearing skies and light breezes are expected to produce sub-freezing temperatures for most areas. For the remainder of the week...the western upper level ridge gradually gains strength and shifts east setting the stage for above average temperatures...low relative humidity...few clouds and virtually no chance for precipitation for the forecast area. Temperatures will run anywhere from 5 to 10 degs f above average for the first part of November. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 930 AM MDT Sat Nov 5 2016 VFR...with mid and high clouds over the region today. Ceilings are expected to remain at or above 10000 feet through tonight. There is a chance for low clouds over far eastern Colorado towards 12z Sunday. At this time, they are still expected to stay well east of the Denver area. Winds are expected to be on the light side through tonight. A weak Denver Cyclone may form later this morning and produce a boundary across the Denver area. Sfc winds west/southwesterly at this time...progged to become east/southeasterly this aftn. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Cooper SHORT TERM...Meier LONG TERM...Baker AVIATION...Cooper
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
951 AM CDT Sat Nov 5 2016 .MORNING UPDATE... Increased PoPs for the northern third of the CWA due to the current radar and satellite trends. Latest HRRR /TTU- WRF indicate shower development in the Austin area through the middle afternoon as well. Increased to CHC PoPs and modified QPF to compensate. Uncertain on coverage in the afternoon as possible outflow may impact the current environment. May increase PoPs farther if that indeed takes shape. Also tweaked hourly forecast grids to ob trends. && PREV DISCUSSION... /ISSUED 415 AM CDT Sat Nov 5 2016/ SHORT TERM (Today through Sunday)... An upper level trough over Texas will pull away taking the showers and thunderstorms currently over Central Texas with it by midday. Patchy fog is possible early this morning. Deep moisture with PWs averaging around 1.5 inches remains over South Central Texas. Even though dynamics are lacking, weak upward forcing on this moisture should generate isolated showers through this evening with thunderstorms possible around peak heating this afternoon. An upper level low currently near the Four Corners region opens up and moves across the Southern Rockies tonight into the High Plains Sunday. Upward forcing, assisted by a favorable upper level jet quadrant, increases along the Rio Grande late tonight and across the remainder of South Central Texas on Sunday. Showers and thunderstorms become more numerous out west late tonight and areawide on Sunday. PWs will rise a little and combined with the possibility of training and slow moving cells, locally heavy rainfall is possible. This may cause minor flooding, especially in areas that received heavy rains over the last couple of days. Clouds and rain will keep temperatures close to normal. LONG TERM (Sunday Night through Friday)... The upper level trough slowly moves across the Southern Plains early next week. Continued upward forcing and upper level diffluence on slightly above normal moisture levels will maintain scattered to numerous showers and mainly isolated thunderstorms Sunday Night and Monday with locally heavy rains possible. A piece of energy dropping down the back side of the trough will carve out another upper level low over the Southwestern/Plains States and/or Northwestern Mexico mid to late week. The models show differing tracks and evolution of this new low. Rain chances will continue mid to late week, however, they slowly decrease as lower level moisture decreases due to surface ridging building into South Central Texas. Temperatures will average near normal. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 74 62 74 63 74 / 30 20 60 70 60 Austin Bergstrom Intl Airport 75 61 75 63 74 / 30 20 60 70 60 New Braunfels Muni Airport 77 63 75 64 75 / 20 20 60 70 60 Burnet Muni Airport 71 60 71 61 71 / 30 20 60 70 50 Del Rio Intl Airport 75 66 75 65 77 / 20 40 60 30 30 Georgetown Muni Airport 72 59 72 62 72 / 30 20 50 70 60 Hondo Muni Airport 79 65 75 64 78 / 20 20 60 50 50 San Marcos Muni Airport 76 62 75 64 74 / 30 20 60 70 60 La Grange - Fayette Regional 77 61 77 65 75 / 30 20 50 70 70 San Antonio Intl Airport 78 65 74 65 76 / 20 20 60 70 60 Stinson Muni Airport 79 65 76 65 78 / 20 20 60 60 60 && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Mesoscale/Aviation...24 Synoptic/Grids...TB3
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1008 AM CDT Sat Nov 5 2016 .UPDATE... Other than bringing the forecast into line with observations, the main aim of this update was to handle precipitation associated with a passing upper trough in the far northwestern parts of the area. Much of the earlier high res guidance had brought the current area of rain to an end right around...now. Clearly that isn`t the case, so keeping the afternoon rain chances in place, and even expanding them southeast just a touch in case there is enough heating on the edge where outflow boundaries may spark new showers. Closer to the coast, drier northeast flow should keep things pretty dry. But, the HRRR and RAP have been generating light showers in this area through the afternoon. With modeled PWATs in the 1.5-1.7 range, matching the morning CRP and LCH soundings, I don`t have the nerve to go totally dry just yet, and will leave just enough PoP to indicate a slight chance. && .PREV DISCUSSION... /ISSUED 624 AM CDT Sat Nov 5 2016/ AVIATION... The backdoor cold front was beginning to push in from the northeast. However, an upper level shortwave trough was generating showers near or at both KCLL and KUTS at 11Z. There were some MVFR conditions just to the west of KCLL and north of KUTS. Expect that there is a small chance MVFR or lower conditions could develop at either site. However, that would be short lived and expect VFR ceilings for most of the day. 40 PREV DISCUSSION... /ISSUED 406 AM CDT Sat Nov 5 2016/ DISCUSSION... A weak s/wv over Central TX is spawning some weak showers over the northwest half of SE TX. The disturbance should continue to influence the region with showers mainly this morning with the precip coming to an end this aftn after the s/wv exits the region. Slightly drier air will work into the region from the NE this afternoon. Max temps will trend slightly cooler but will remain above normal over the southern zones and near normal over the north today. Tranquil weather will dominate tonight. Some showers will develop near the coast toward morning with some speed and directional convergence. An upper level low over the desert SW will will move east on Sunday. Lift will increase over SE TX and PW values will increase to 1.60 to 1.70 inches. Fcst soundings look semi-saturated by afternoon and would expect showers to increase in coverage. Have tapered PoPs highest in the SW zones and lower to the NE. The trough nudges ever so slowly to the east Sunday night and Monday. Fcst soundings look saturated with PW values between 1.70 and 1.90 inches. Jet dynamics still look rather impressive with SE TX in a 75 kt LFQ and a well defined splitting jet structure. Would expect widespread precipitation Sunday night into Monday. The dynamics and subtle negative tilt in the upper trough axis supports locally heavy rain late Sunday night into Monday. The ECMWF and GEM keep the rain going on Election Day and with the upper trough still to the west and an active jet overhead, feel it`s best to lean toward the more aggressive and wetter ECMWF. The upper level trough axis remains west of SE TX through the week but both the GFS and ECMWF develop a sfc low over the northern Gulf late Tuesday and this feature will drag most of the precip to the north and east of the area. The upper flow also becomes more confluent with time imparting subsidence over the region. Drier and cooler air will filter into the region Wednesday onward. Seasonal temps and dry weather will prevail for next weekend with a W-NW upper flow. 43 MARINE... Not many marine impacts are expected today. Tide levels only reached 2.6 feet last evening and the overall tides were only between one- half and one foot higher than normal this morning. Starting on Sunday, the early part of the new week may again see some marine impacts. Showers and thunderstorms will return on Sunday and become more likely Sunday night through Monday night. Northeasterly winds are expected to reach caution levels by Sunday night. The moderate northeast to east winds will help raise the tide levels along the coast and may again begin affecting at least the Bolivar Peninsula during the times of high tide late Sunday night and Monday. Diminishing impacts are expected by late Tuesday or on Wednesday. 40 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 74 60 77 62 73 / 30 10 40 60 70 Houston (IAH) 80 63 80 64 75 / 20 10 40 60 70 Galveston (GLS) 78 72 79 68 77 / 20 20 40 60 70 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ Discussion...25
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
411 AM PDT Sat Nov 5 2016 .SYNOPSIS... Above normal temperatures and dry weather will prevail across central California this weekend and through the upcoming week. Otherwise, patchy fog will be possible throughout the San Joaquin Valley each morning. && .DISCUSSION...High pressure aloft remains in control with clear skies and light winds prevailing over central California. Fog is the main concern again this morning but thus far has not formed. Visibilities in the San Joaquin Valley have generally been in the 1-3 SM range, though Madera and Hanford have both fallen to 3/4 mile. But GOES GEOCAT LIFR probability has increased along and west of the Hwy 99 corridor from Merced to Hanford in the last half hour. The HRRR shows vsbys in this area dropping further through sunrise, but it was showing the same thing yesterday and they did not. So will continue to monitor the potential for some dense fog but it does not seem likely at this time. Water vapor satellite imagery shows an upper trough off the Pac NW coast with an impressive band of moisture (PWAT ~ 1.5") ahead of it. Models agree that this moisture will stay to our north as the trough moves inland tonight, with just a few mid/high clouds for our area. The trough will increase the onshore surface pressure gradient today, resulting in windy conditions through and below the Kern County mountain passes tonight into Sunday. Westerly wind gusts are not expected to reach advisory levels but 30-40 mph is likely in some areas, such as around Mojave. Winds will diminish Sunday night as the gradient relaxes and turns offshore on Monday with light easterly winds through the week. Dry conditions are are also expected to prevail throughout the upcoming week as a positively tilted upper ridge amplifies over the western CONUS. Conditions will be favorable for fog in the SJ Valley each night. Temperatures today will be similar to yesterday with some areas up a degree or two. The trough tonight will knock temps down slightly on Sunday, but they will rebound under the ridge early next week. Highs will generally be around 7-10 degrees above climatological norms, with the exception of Sunday when they briefly lower to around 5 degrees above normal. && .AVIATION...In the San Joaquin Valley, areas of MVFR visibilities due to haze for the next 24 hours. However, IFR with local LIFR visibilities will occur in fog between 12z and 18z Saturday. VFR conditions can be expected elsewhere over the central California interior during the next 24 hours. && .AIR QUALITY ISSUES... On Saturday November 5 2016...Unhealthy for sensitive groups in Kings County. Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Fresno...Kern...Kings...Madera...Merced and Tulare Counties. Further information is available at Valleyair.org && .CERTAINTY... The level of certainty for days 1 and 2 is high. The level of certainty for days 3 through 7 is high. Certainty levels include low...medium...and high. Please visit www.weather.gov/hnx/certainty.php for additional information an/or to provide feedback. && .HNX Watches/Warnings/Advisories... NONE. && $$ public...DCH avn/fw...Riley synopsis...DCH weather.gov/hanford
Area Forecast Discussion
National Weather Service Lincoln IL
1023 AM CDT Sat Nov 5 2016 .UPDATE... Issued at 1023 AM CDT Sat Nov 5 2016 See little to change in forecast this morning as high pressure continues to dominate the region today. High clouds may temper the MaxT forecast suggested by 12z KILX sounding which is in line with current package. Still 5-10F above normal for early November. && .SHORT TERM...(Today and tonight) ISSUED AT 232 AM CDT Sat Nov 5 2016 Main concern initially is the extent of fog early this morning. RAP soundings in Bufkit indicate we could spike down with some locally dense fog again around sunrise in many locations of central and southeast Illinois. Hydrolapse plots show increasing moisture with height in the lowest layer of the air mass, which is one primary indicator of fog formation. HRRR and RAP visibility forecasts are focusing fog west of Decatur to Bloomington and south of Peoria to Canton. Therefore, have expanded fog into a majority of the forecast area for the first couple of hours of the morning. Not confident enough to issue a dense fog advisory at this point due to uncertainty on coverage, but will monitor closely as the night progresses. High surface pressure will dominate the remainder of the short term forecast, with mostly sunny skies today and mostly clear skies tonight. Light fog will be possible again late Saturday night due to little change in air mass, and have included patchy fog in many areas again. High temperatures today look to climb above normal, with the help of southerly winds and nearly full sunshine. Guidance numbers were generally followed with highs expected to reach the upper 60s west of I-55 and the mid 60s east of I-55. Lows tonight should bottom out in the lower 40s, based on expected lowest afternoon dewpoints. .LONG TERM...(Sunday through Friday) ISSUED AT 232 AM CDT Sat Nov 5 2016 Main theme for next week continues to be with temperatures remaining well above normal for early November. While the GFS and ECMWF have some significant differences with the Tuesday wave, both keep the colder air over Canada. By late in the week, a pattern change starts to set up, with a slug of colder air dropping into the Great Lakes. Will watch this for the upcoming forecast cycles as this is largely beyond the current forecast range, but current indications are that it would be short lived. Regarding the wave in question, the latest models are in reasonable agreement through Monday evening, with the wave extending across the eastern Dakotas to along the Manitoba/Ontario border. However, the latest ECMWF breaks off a piece of energy along the southern part of the wave early Tuesday, and drops it southwest into Texas by Thursday morning. This is a significant shift from the morning run and rather suspect at the moment, so went with a blend of the current GFS and the old ECMWF instead. With the greater lift near the Great Lakes, have kept PoP`s in the slight chance range for Tuesday and Tuesday night. The late week short wave passage currently appears dry. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) Issued at 624 AM CDT Sat Nov 5 2016 Some patchy fog with MVFR vsbys are still possible in the 12z- 13z time frame, based on dewpoint depressions of 0-2F. Thin cirrus arriving from the west will limit any dense fog formation, so will not include any IFR visibility conditions this morning. Otherwise VFR conditions will prevail for the remainder of the forecast period. An axis of high pressure extending across Illinois from east to west will only drift slowly to the E-SE today. Expect minimal cloud cover through tomorrow, with mainly cirrus clouds from time to time. Winds will start out light and variable this morning, then become southwest in the 7-10kt range by mid to late morning. Winds will become light southwest by sunset. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Barker SHORT TERM...Shimon LONG TERM...Geelhart AVIATION...Shimon
Area Forecast Discussion
National Weather Service Portland Oregon
329 AM PDT Sat Nov 5 2016 .SYNOPSIS...Today will be a wet day for much of the forecast area, as strong low pressure off the British Columbia coast drags a slow- moving but very moist cold front across SW Washington and NW Oregon. Areas east of Interstate 5 will probably have a dry morning, but the rain will increase quickly after late morning or midday. Rain may be locally heavy at times, even over the inland valleys, which may cause some localized urban or small stream flooding issues... especially where storm drains are clogged. An upper level trough will finally shove the front east of the Cascades this evening, with rain tapering to showers. A few showers will linger into Sunday, then high pressure and offshore flow will bring another round of dry and mild weather Monday and likely Tuesday. && .SHORT TERM...(Today through Monday)...After a day of record warmth at some locations across the CWA Friday, big changes are in store today as a very moist frontal system slowly moves onshore and crosses Western WA/OR. Heavy rain has already moved onshore in Washington, where personal weather stations on the Long Beach Peninsula have already reported around 0.50 to 0.75" of rain just since midnight. Higher amounts have occurred on the Olympic Peninsula where 2+ inches have already fallen near Forks. This is a testament to the moisture- rich air mass along and ahead of the front, where precipitable water values are up near 1.50". The surface cold front appears to be right over KLGX radar, evident on the lower elevation velocity and reflectivity products. Some locally gusty S winds up to 40-50 mph will be possible along the front for the beaches, headlands, and exposed areas in the Coast Range. The front is moving eastward/ onshore at a proverbial snail`s pace, likely less than 10 mph. With precipitable water values at 3-4 standard deviations above normal for the time of year, strong dynamics, but a slow moving front, the potential is there for substantial rain totals as this front slowly crosses the Willamette Valley. S-SW winds on the order of 35-45 kt at 850 mb will provide good orographic enhancement on favored slopes. The typical higher amounts will occur along the coast and Coast Range, where 2-4 inches of rain are possible by the time rain tapers to showers on the cold side of the front. However, the real potential for problems may be over the interior lowlands and urban areas as rain develops later this morning and intensifies during the afternoon hours. Satellite water vapor imagery shows a nice batch of convection developing along the front off the northern CA coast, the debris of which will likely become absorbed by the front and produce a solid steady rain as the front moves slowly across the forecast area later today. Weak waves of low pressure along the front - likely impossible for models to really initialize well over the ocean - will further hold up the front`s progress as it tries to get across the Willamette Valley today. Meanwhile, higher resolution models such as the HRRR and WRF show excellent surface convergence along the front, while model soundings show a well-saturated atmosphere from the surface almost all the way up to the tropopause. Conditional instability and favorable right- entrance jet position/dynamics will also be in play. A sharp and slightly negative-tilt upper trough now just north of 40N/140W will finally shove the front eastward later this afternoon into tonight as it approaches and pivots E-NE through Oregon. All of this points to the potential for a 1-3 hour period of very heavy rain rates in the Willamette Valley near the front this afternoon, somewhat similar but probably not quite as intense as the Halloween event in 2015. Some locations could exceed an inch in that short time period, with some upside potential. Who gets impacted by this will largely depend on where the front and moisture axis are as the approaching upper trough enhances synoptic lift. The most likely area appears to be along or just east of the I-5 Corridor, which would likely impact portions of the Portland, Salem, and Eugene metro areas. Areas with poor drainage, clogged storm drains, and/or flashy small streams may have some minor flooding issues as a result. It is highly recommended that those who live in urbanized areas take one more look at their storm drains this morning before rain really starts to increase. Will likely issue a Special Weather Statement, as confidence on impacts and whether all these ingredients will come together over urban areas is not quite high enough to warrant an Areal Flood Watch yet. Of important note for media and those following along with their favorite weather apps is that the main radar for NW Oregon, KRTX on Dixie Mtn, remains down due to a major mechanical failure. The rain will not show up as heavy as it should on composite radar imagery, or possibly not at all the further south one gets from Portland and Tillamook. The main point of mentioning this is a reminder that what you see on radar imagery may not accurately reflect the situation this afternoon. We will monitor closely using all the other tools at our disposal, such as rain and stream gages, satellite imagery, weather spotters, and numerous other tools. The steady/heavy rain will quickly taper off from west to east this evening as the upper trough moves onshore, pushing the deepest moisture east of the Cascades. There may be just enough instability with the upper trough for a couple thunderstorms along the North Coast, so left those in the forecast. Snow levels may briefly lower enough to dust Santiam and Willamette passes with a little wet snow Sunday, but impacts should be minor. A warm front may spread just enough isentropic lift over the area Sunday night/early Monday morning for some areas of light rain, mainly for the NW portion of our CWA. Otherwise, the trend will be for warmer and drier weather Monday as high pressure builds northward across the area and puts us back into a similar mild and dry offshore flow pattern to what we had Thu/Fri. Widespread 60s will be possible again Mon/Tue, especially if skies remain partly to mostly sunny. Weagle .LONG TERM...Strong upper level ridging is expected to build across the Western CONUS behind Monday morning`s weak warm front. 00z deterministic models are coming into better agreement on holding off rain associated with the next frontal system well into Tuesday, which is somewhat expected considering the strength of the downstream ridge and the drying offshore flow Mon/early Tue. The past couple days, most models have been trending toward keeping the Western CONUS ridge strong through midweek, which would likely make it difficult for the midweek front to pack much punch rain or wind-wise. Best chances for rain will be along the North Coast, with lesser chances to the SE Tue through early Wed. Given this, decided to decrease PoPs a good bit south and east of the Coast Range Mon/Tue. The upper ridge then reasserts itself after this system, with another round of mild and dry offshore flow expected Thursday before upstream jet energy from the Pacific forces the ridge to lean over with a positive tilt Friday...possibly enough for the next front to bring a decent chance for rain by Fri/Sat. Weagle && .AVIATION...Very slow moving cold front offshore will push inland this am, and will be over the Cascades by late afternoon. Will see and abrupt lowering of cigs as the rain spreads inland this am, with VFR transitioning to MVFR over much to the interior after 16z. Generally, MVFR and areas of IFR conditions will remain along the coast through the day, though may see slow improvement to VFR towards evening. Expect mtns to become obscured in precip and clouds most of the day. KPDX AND APPROACHES...VFR this am, but as rain increases after 16z, expect MVFR cigs to increase soon after. Still thinking that 17Z to 01Z will be generally MVFR conditions, mainly as CIGS but occasionally with rain. Showers tonight, but think may take bit longer for CIGS to increase to VFR. Typical with slow moving fronts to have CIGS slow to respond after frontal passage mainly due to lingering low level moisture behind the front. rockey. && .MARINE...Getting gusts in the 30 to 35 kt range this am, so current Gale warning looks on track. With the front moving rather slowly, now sure if will see Gales completely diminish by 5 am. Still think that front will be close enough to the coast that strongest winds will have eased, with gusts 20 to 30 kt likely for rest of this morning. Seas running up to 15 to 16 ft this am, but as winds ease, so will the seas somewhat. But baseline westerly swell of 14 to 15 ft will build later today, with mostly 16 to 18 ft tonight into Sun am. Higher swell will be over the outer waters. Another system approaches late Sunday and into Monday will possible gales again. But seems to be a repeat of what have seen on Fri, with south to southeasterly winds being the stronger well offshore. Will trend forecasts in that direction. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Gale Warning until 5 AM today on all coastal waters. Small Craft Advisory for Rough Columbia River conditions today through Sunday am. && $$ Interact with us via social media: www.facebook.com/NWSPortland www.twitter.com/NWSPortland This discussion is for Northwest Oregon and Southwest Washington from the Cascade crest to 60 nautical miles offshore. The area is commonly referred to as the forecast area.
Area Forecast Discussion
National Weather Service Denver/Boulder CO
243 PM MDT Sat Nov 5 2016 .SHORT TERM...(This evening through Sunday) Issued at 130 PM MDT Sat Nov 5 2016 An upper low located near the Four Corners region this aftn is progged to move slowly east/northeast through Sunday. For tonight the flow aloft will continue to be southerly, then the flow aloft will weaken and become west/northwesterly on Sunday as the trough moves eastward. Weak mid level qg ascent coupled with some aftn instability has allowed for sct to nmrs rain and snow showers in the high country today, especially south of interstate 70. Overall will maintain sct pops in the mountains overnight. Not much in the way of accumulating snowfall expected at this time. Across the northeast plains, isold showers from around denver southward are progged to weaken as they move northward this aftn and evening. The latest HRRR runs continue to reflect this trend. Will keep isold pops in the grids mainly along and south of the interstate 70 corridor. The mdls continue to show low level moisture/stratus over the eastern plains tonight...and continue to keep it east of Denver Sunday morning. On Sunday, weak qg ascent will continue ahead of the upper trough axis with increasing mid level subsidence fm west to east. Will keep scattered pops in the mountains through early aftn with isold pops on the far eastern plains, should see them all decreasing in the afternoon. .LONG TERM...(Sunday night through Saturday) Issued at 130 PM MDT Sat Nov 5 2016 The potential for showers will diminish over the high country and far eastern plains Sunday night as a shortwave ridge moves in, however following close on its heals a shortwave trough will push in Monday morning. Due to the limited depth of moisture and downward QG motion, have kept out any chance of precipitation over the high country, however there may be a few flurries/sprinkles Monday morning. A cold front will push south over the plains Monday for highs to be about 5 degrees cooler. Some clouds in the morning should give way to mostly clear skies later in the day. The rest of the week and into the weekend will feature abnormally warm and dry weather as the strong upper ridge over the western states and into the Northern Rockies prevails. A weak cool push is expected Thursday to surge down the plains for a slight cool down. Otherwise temperatures will be 10 to 15 degrees warmer than average for this time of year. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 130 PM MDT Sat Nov 5 2016 VFR conditions expected through the period. Generally southerly winds this aftn and overnight. Weakening showers moving across Denver from south to north not expected to impact the terminals as they pass across the Denver area. Could see brief bkn cigs in the 080-10kft range this aftn, but overall cigs will be much higher. Mdls continue to show stratus over the plains of northeast and east central CO tonight into Sunday morning, but this remains well east of the Denver area. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Cooper LONG TERM...Kriederman AVIATION...Cooper
Area Forecast Discussion
National Weather Service Buffalo NY
412 PM EDT Sat Nov 5 2016 .SYNOPSIS... High pressure ridged from the Ohio Valley to the Upper Great Lakes will slowly drift eastward to the Atlantic coastline through Tuesday... while maintaining dry and seasonably mild weather across our region. A weak cold front will then cross the area Tuesday night along with some scattered showers...with dry and quiet weather then returning for Wednesday and Thursday. && .NEAR TERM /THROUGH SUNDAY/... High pressure will persist across Western New York tonight, providing another mainly dry night. A weak shortwave is forecast to track across the North Country tonight, but with limited moisture this will should bring only an increase in cloud cover this evening, before drier air moves in later tonight. HRRR and other higher resolution models show a cloud streak across the eastern end of Lake Ontario to the Tug Hill Plateau area, but no indication of precipitation. Even with a northwesterly wind overnight, expect neutral temperature advection so there will not be substantial cooling. Low temperatures in many areas will be in the upper 30s to lower 40s. High pressure remains across the region on Sunday, with the center of surface high pressure settling in across the easter Great Lakes and Western New York. Some thin high clouds may stream across the region on a north-northwest flow far aloft, but otherwise it will be a mostly sunny and dry day. High temperatures will climb to the lower 50s across Western New York west of the Genesee Valley with mid to upper 40s over Central and Northern New York where temperatures aloft will be a little cooler. && .SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... Monday into Tuesday will be characterized by fairly quiet weather and a warming trend to above normal temperatures again. By late Tuesday into Wednesday night a cold front will cross the region, bring some scattered showers followed by a return more normal high temperatures Wednesday. Looking at the details, Sunday night will be quite chilly across the region. As we get caught between the departing low pressure system off the New England Coast and the amplified ridge axis building in across the upper Great Lakes, the surface high will settle over the area Sunday night. This cool, dry airmass, along with light winds under the center of the surface high will result in optimal radiational cooling conditions. Freezing temperatures are likely across most locations expect for the lake plains locations, which are more likely to remain just above freezing in the mid 30s. Areas of frost will likely develop overnight, especially east of Lake Ontario and across the Southern Tier. Monday into Tuesday will give a warming trend as the sharp ridge axis over the upper Great Lakes moves across the region Monday and across New England by Tuesday. As the surface high tracks off the Mid-Atlantic coast, so will the shallow cool airmass, bringing a return to southwesterly warm advection ahead of the next approaching shortwave to cross region the Tuesday night into Wednesday. Tuesday looks to be fairly breezy across the region as the wind is accelerated ahead of the approaching wave and cold front, with gusts 25 to 30 mph across the typical breezy lake plains locations and Niagara Frontier. There will be a gradient in temperatures across the region Monday, with low 60s from the Genesee Valley westward, tapering off to the low 50s across the North Country, which will remain closer to troughing aloft and cooler temperatures. By Tuesday, the deepening southwesterly flow across the area will result in fairly mild temperatures across western and north central NY. Downslope regions from the Genesee Valley across the northern Finger Lakes may surge into the low to mid 60s, while most other locations see highs in the upper 50s to low 60s. By late Tuesday afternoon into Tuesday evening, a fast moving shortwave trough will move from the upper Great Lakes to the lower Great Lakes, breaking down and shunting the upper level ridging off the East Coast. The wave and associated cold front should pick up just enough mid-latitude moisture from the central plains to result in at least scattered showers across the region Tuesday night. On Wednesday, the synoptic forcing and deep moisture will already be displaced well to our east into New England. However, the cold advection in the northwesterly flow behind the wave, along with shallow synoptic moisture will likely result in some lingering lake enhanced and orographic enhanced areas of drizzle and low cloud cover, especially southeast of the lakes. High temperatures on Wednesday will be near seasonal normals in the low 50s. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... The long term forecast is starting to trend toward a pattern more conducive for unleashing snaps of colder air across the Great Lakes and northeast from mid-November through probably the end of the month. The key to this pattern change remains the anomalously strong ridge now across the central CONUS. Global ensembles agree on maintaining and redeveloping this strong ridging while retrograding it slowly westward with time. By late next week, this ridge is expected to amplify to record high H25 heights for this time of year (per NAEFS climo) over the inter- mountain west as far north as the arctic circle in western Canada. The result for us here in western NY will be the development of northerly flow from the arctic circle to the Great Lakes, allowing for an outbreak of cold air across the Great Lakes for the weekend. GFS and EC ensembles are coming into much better agreement on this troughing and colder air now, with the operational runs showing 850 mb temperatures of -9 to -10 C over NY State Saturday afternoon. Have used a consensus of the raw model guidances for temperatures into the weekend, as much of the MOS and bias corrected guidance will not perform well at this range and under a significant pattern change. This could result in high temperatures in the low to mid 30s on Saturday and in the mid 20s to low 30s for Friday and Saturday nights. Temperatures this cold under the upper level trough tracking from the Hudson Bay to Maine will result in a lake response in the northwesterly flow. This lake response will be aided by any shortwaves rotating around the parent trough and synoptic moisture trapped within the parent trough. Some locations southeast of the lakes may see some of their first lake effect snow of the season, though it is much to soon speculate on placement and intensity. Looking farther ahead, through the end of the month, longer range models such as the CFS are showing a more persistent pattern of ridging across western Canada and into Alaska and along the west coast, which would help keep the door open to colder outbreaks of air across the Great Lakes and northeast CONUS. The most recent 3 to 4 week outlook from the Climate Prediction Center also highlights the Great Lakes region for potential below normal temperatures to end the month of November. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... A weak shortwave will approach this evening which will bring increasing cloud cover to parts of Central and Northern New York. There are also indications of lower ceilings across the Southern Tier, with possible IFR to the east of KJHW. Have included SCT IFR cloud at KJHW for a period from 03Z to 10Z. Expect VFR conditions across the rest of the region, and for the entire forecast area during the day on Sunday. Outlook... Sunday night through Tuesday...Mainly VFR. Tuesday night...MVFR/IFR in showers. Wednesday and Thursday...MVFR/VFR. && .MARINE... Winds and waves have fallen to below advisory levels on western Lake Ontario...allowing for the cancellation of the small craft advisory for that region. Elsewhere...brisk winds and choppy conditions will persist across Lake Erie and eastern Lake Ontario into this evening...for which small craft advisories remain in place. Winds and waves will diminish later tonight and Sunday as high pressure builds across the region, with winds varying from northerly early Sunday to southerly by Monday morning. Stronger southwest winds will develop on Tuesday, then a cold front is expected to move through on Tuesday night with a shift to northwesterly flow. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...Small Craft Advisory until 11 PM EDT this evening for LEZ040- 041. Small Craft Advisory until 11 PM EDT this evening for LOZ044-045. && $$ SYNOPSIS...JJR NEAR TERM...WCH SHORT TERM...CHURCH LONG TERM...CHURCH AVIATION...WCH MARINE...JJR/WCH
Forecast discussion for routine afternoon forecast issuance

.SHORT TERM...Tonight and Sunday Issued at 220 PM CDT Sat Nov 5 2016 The latest RAP analysis and satellite/radar imagery show a massive high pressure system centered over the Ohio Valley. Besides just some wispy cirrus, skies are mostly clear across the region, and also upstream over the northern Mississippi Valley and Dakotas. With the surface high moving little through the end of the weekend, temps and prospects for fog are the main forecast concerns. High pressure through the column will remain across the region tonight and Sunday. The airmass within this high remains very dry, so looking at mostly clear and calm conditions over the period. These conditions will support another night of ground fog late tonight into early Sunday morning away from the lake. Because winds in the boundary layer are weaker than last night, think fog has potential to be more widespread and dense so increased wording in the forecast. Not much change to temps over the next 24 hours. Projected 925mb temps on Sunday look similar to todays, so highs should continue to top into the middle to upper 60s. .LONG TERM...Sunday Night Through Saturday Issued at 220 PM CDT Sat Nov 5 2016 Well above normal temperatures and a few opportunities for light showers will be the general rule for the upcoming extended period. A cold front will sweep through the western Great Lakes Monday night, bringing the chance for light showers late Monday across the northwest cwa, and through the rest of the area Monday night. Rain chances will be relatively low given the limited moisture available to this northern stream system, mainly in the chancy category. The push of cold air behind this system will be relatively unimpressive, with temperatures on Tuesday although they will be several degrees cooler than Monday, will still be several degrees above normal for this time of year. The next system of consequence tracks to the north on Thursday and brings a cold front through the area during this time period. The fropa itself will be dry given very limited moisture. However there will be a chance for some showers across the northern cwa on Friday behind the front as a mid level shortwave takes advantage of a favorable fetch for some lake effect moisture to make it into the column for some rain shower activity. Even with this setup rain chances will be relatively low given the lack of deep moisture available to the shortwave. Some showers are possible in northern Wisconsin on Friday as a cold front and some mid level short wave energy pass. The front will bring the coldest daytime highs that the forecast area has seen for a while. Even so, it will still be warmer than normal with highs mostly in the 45 to 50 degree range. Temperatures behind the departing cold front Friday and Saturday will be quite cool compared to recent temperatures. Despite this cooler weather temperatures will only cool to around climatological normals for this time of year. && .AVIATION...for 18Z TAF Issuance Issued at 1235 PM CDT Sat Nov 5 2016 High pressure will remain in place through the end of the weekend. Only aviation concern is the potential for fog development late tonight into early Sunday morning away from Lake Michigan. Like the last few nights, ground fog may form after 9 or 10z tonight and last through 14z or so, with some places falling below airport minimums. Any fog that forms will dissipate after 15z and then more excellent flying weather for Sunday and Sunday evening. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......Kurimski AVIATION.......MPC