Aikyam-Lab/Synoptic-Bench huggingface dataset:
Satellite imagery clearly shows an upper low circulation centered over the British Columbia/Idaho/Montana border this morning. The low is weakening and will remain nearly stationary through this evening. Circulation around the low is sending clouds and moisture into the northern third of the area today. Models are showing some instability over the Washington Cascades and the higher terrain of the Northeast Oregon mountains. With the low weakening, expect that thunderstorms will cut off fairly rapidly in the late afternoon though the Washington Cascades may see a few rain showers into the late evening. With the low weakening expect that temperatures will be up a degree or two from yesterday. An upper level low will drift east across southern Canada today. Southwest flow from this low will bring moisture and instability to the Cascades and from central to northeast Oregon.
1008 AM EDT SAT JUL 16 2016 An upper-trough will swing through the eastern Tennessee Valley and Southern Appalachians this afternoon. Chattanooga Airport, TN 92 70 93 73 / 40 30 30 20 Knoxville McGhee Tyson Airport, TN 90 69 91 71 / 50 20 20 10 Oak Ridge, TN 90 68 91 72 / 50 20 20 10 Tri Cities Airport, TN 87 64 89 68 / 40 20 20 10.
622 AM CDT SAT JUL 16 2016 A broad high pressure ridge is dominating much of the Midwest this morning, with a stalled frontal boundary draped along the Ohio River Valley. The cooler airmass will keep todays highs in the upper 70s and lower 80s with generally light winds out of the east/southeast. Tonight will be a little warmer, into the 60s with increased cloud cover inhibiting a rapid cool down as the next weather system moves into the region. As the massive 597 dm upper high remains anchored over the Kansas/Oklahoma area, possibility of some ridge-rider MCS's tracking over our area exists.
A ridge of high pressure will build back towards the Panhandles throughout the day today.
945 AM EDT SAT JUL 16 2016 Southeasterly flow has deepened this morning with ridge nudging very slowly northward. Low-level ridge axis drifting slowly north from the central toward northern peninsula into Sunday.
Other sensible weather will feature a light NNW wind with highs a bit cooler than yesterday in the mid to upper 80s. Surface ridging and relatively benign zonal flow aloft will allow for a dry period of weather to end the weekend. After lows in the mid and upper 60s tonight, Sunday night lows will be milder in the lower 70s. Sunday will be noticeably warmer with highs mostly in the low 90s.
In the mid levels, a weakness in the ridge persists. Models are progging a shear axis to move through today, before ridging begins to build in later tomorrow. With the upper ridging trying to build eastward on Sunday, convective coverage may be a bit more suppressed.
Otherwise cloud cover ranges from FEW to BKN allowing for temps to rise into the low/mid 80s as of 15Z. The cold front is still back in southern IL and MO but the upper- level short wave will be enough to trigger off scattered showers and thunderstorms today. Then, a weak cold front may bring the possibility for -TSRA btwn 16/19Z-19/01Z.
A ridge axis of high surface pressure will pass eastward through our region today, beginning a slow transition to easterly, then a southerly low level flow over the weekend. The mid/upper levels will undergo increasing ridging this weekend, making measurable pcpn unlikely across the region, though the northern stream should remain active with periodic MCSs just to our north.
The surface cold front was situated from northern KY to along the AR-MO border. Looking for highs today to easily reach the lower 90s before thunderstorms develop.
1021 AM CDT SAT JUL 16 2016 Temps this morning starting out a degree or two cooler than yesterday at this time. Suspect cloud cover will thin out enough whereas readings rebound close to the highs observed yesterday.
915 AM MDT SAT JUL 16 2016 Upper-level low pressure system remains nearly stationary over southeast corner of BC and far northern ID. The low is expected to drift only slightly eastward today, keeping clouds/showers/isolated thunder over most of the forecast area, though southwest MT will see less cloud cover and precip than central/Hiline areas. A few scattered showers/thunderstorms will continue to move northeastward through the region through the period as a slow moving upper level low begins to stall out just north of Glacier Park.
1032 AM EDT SAT JUL 16 2016 Aviation sections updated High pressure will result in dry conditions through tomorrow.
629 AM CDT SAT JUL 16 2016 A large convective complex continues to push across SW OK at this time, with most of the low level moisture transport feeding this complex. Ketcham Expect the subtropical ridge to continue to build across the plains for the beginning of the week. The higher surface dewpoint air will probably keep max temps in the upper 90s as heating goes to burning off the higher dewpoint air, but expect heat index values of 100-105 by the Mon-Thu. Tonight as the pressure gradient holds strong and the low-level jet develops across the region, expect the gusty winds to linger through the overnight hours.
1135 AM EDT SAT JUL 16 2016 High pressure will provide another day of seasonably cool and less humid conditions. except a bit cooler near Lake Michigan.
Expect VFR conditions to prevail across the Rio Grande valley and northern ranchlands today as the 500mb ridge across the southwest United States and northern Mexico continues to provide subsidence across the area. /issued 429 AM CDT SAT JUL 16 2016/ SHORT TERM (Today through Sunday): 500mb ridge across the southwest United States and northern Mexico extending into Texas this morning will continue to provide subsidence across the CWA today before a weak 500mb low/inverted trough across the western Gulf of Mexico this afternoon moves westward towards the lower TX coast tonight and moves inland across northeast MX and deep south TX Sunday. Temperatures will continue to be hot today and with higher dewpoints across the lower TX coast.
Weak ridge remains over the area with vigorous short wave pushing into western North Dakota from Montana. Upper low continues to slowly track to the east while the next potent short wave ejects and gets wrapped into broad cyclonic flow to the southeast of aforementioned Hudson Bay system. Still some question on how far north this will develop with the fly in the ointment being the effect the morning convection will have on this along with lingering cloud cover and cooler temperatures to the north of a warm front. Broad ridge builds into the area to start the upcoming work week with a warming trend developing. Occasional weak disturbances moving through the ridge will bring low chances for thunderstorms to portions of the area from time to time.
As the high pressure pulls east, pressure gradient will begin to tighten into the afternoon with increasing south winds. Despite the increasing warm advection, temperatures will remain below normal for another day as thermal trof lingers just east of the state today.
526 AM MDT SAT JUL 16 2016 08z surface analysis had low pressure over central WY with frontal boundary into central SD. Today and tonight, upper low over southeast BC will elongate and shear out as it stretches out over the US/Canadian border. Atmosphere should destabilize quickly today as plume of steep 700-500mb lapse rates overtops dew points pooling in the lower 60s. As upper trough digs across the northwest US, upper ridge builds into the CWA. Upper level ridge over the central CONUS will amplify as a trough develops over the Pacific Northwest.
Additionally, upper ridging continues to dominate Texas this morning but this feature is weaker than 24 hours ago. The combination of disturbances rotating under the ridge (taking a more northerly trajectory across the region) and increasing moisture raises concerns for greater convective coverage along the sea breeze later today. /ISSUED / Upper ridging from near SHV to DRT will help to keep the heat on and limit rain chances to mainly the eastern and coastal areas today. The upper flow should veer a little today and in combination with the gradual increase in low level moisture will carry 20-30 pops generally along and southeast of the Highway 59 corridor.
An upper level low will drift east across southern Canada today. Southwest flow from this low will bring moisture and instability to the Cascades and from central to northeast Oregon.
With nearly 40 knots of bulk shear in the lowest km, could see an isolated tornado in the early evening hours, but think the focus will really be on the wind potential. Highs will reach the lower to mid 80s.
High pressure over the southern Rockies will gradually shift east through the weekend. An upper level low along the Canadian border near the Idaho/Montana shared border will remain nearly stationary through the day today. A gradually deepening upper level low off the coast of the Pacific Northwest will help to induce a southwesterly gradient across the desert southwest. A weak cold front will stall across northern Utah today.
720 AM EDT SAT JUL 16 2016 Aviation High pressure will bring fair weather into Sunday.
High pressure will then build into the region tonight. The high will depart to the east on Sunday. A southerly flow on the back side of the high will lead to an increase in humidity.
KILX and KDVN soundings suggest that previous highs were a bit on the high side as well given well mixed forecast temps remaining in the upper 70s in this band. A broad high pressure ridge is dominating much of the Midwest this morning, with a stalled frontal boundary draped along the Ohio River Valley. The cooler airmass will keep todays highs in the upper 70s and lower 80s with generally light winds out of the east/southeast. Tonight will be a little warmer, into the 60s with increased cloud cover inhibiting a rapid cool down as the next weather system moves into the region. As the massive 597 dm upper high remains anchored over the Kansas/Oklahoma area, possibility of some ridge-rider MCS's tracking over our area exists.
Dew points are in the low teens and skies are clear so temperatures will likely continue to fall slowly through sunrise. Morning lows may get to 15 in the coldest locations with most of us in the low to middle 20s. Latest surface analysis depicts strong arctic high pressure centered over northern Missouri, with resulting northerly surface flow over the local region. 21z H5 analysis depicts a longwave trough axis extending from eastern Canada southward along the Atlantic seaboard, with a ridge axis over the western half of CONUS.
There will be a window where freezing drizzle will be possible across far northeast Oklahoma as evaporative cooling offsets the WAA. Temperatures will begin to rise above freezing late tonight as southerly winds continue to increase.
103 AM EST Fri Dec 16 2016 Cold high pressure will build over the area tonight and Friday. The high will slide offshore Friday night with a warm front lifting north through the region late Friday night and early Saturday.
The coastal trough/warm front is expected to remain near the coast overnight but gradient may increase over the offshore waters for southeast winds to approach SCA.
105 AM EST Fri Dec 16 2016 High pressure over the Ohio Valley will build into Pennsylvania tonight.
348 AM CST Fri Dec 16 2016 Leading edge of strong upper trough moves onto the OR/CA coast early today with the base of the trough swinging ashore this evening.
South of a warm front and in the warm sector, highs should peak into the lower 70s. To the northeast, much cooler temperatures with values peaking in the 30s is expected. In the meantime, freezing fog is starting to thicken across the region and will continue through the morning hours. By this evening, a strong cold front will slam southward across the forecast area. Otherwise, other than some freezing drizzle early this morning across the southeast zones, today should be precipitation free. At the low levels, a very strong baroclinic boundary is expected.
Some relief from these cold temperatures is on the way tomorrow when this high pressure slides off the Atlantic seaboard and starts us into a strong southerly flow. Look for isolated/scattered showers after 00Z at BNA & CKV and MVFR ceilings with the approach of a strong cold front.
Further south, moisture remnants from yesterday's warm front will keep a threat for flurries or brief light snow across SE WA and lower Idaho Panhandle with the potential for up to an inch of light and fluffy accumulations. temps will plummet to or below zero with the potential for freezing fog aft 06z.
Falling temperatures will result in impacts to roadways over the higher passes soon if not already an issue. However, high density snow and surface temperatures still above freezing in many mountain areas likely not allowing much accumulation until later this evening when the Winter Storm Warnings go into effect. Max temperatures Friday are expected to moderate to above normal at most locations within our CWA ahead of the cold front. Cold front still looks to enter NW corner of our CWA in NE Utah Friday afternoon and then gradually spread southeast across our CWA through Friday evening. The upper trough will be moving east of our CWA Saturday afternoon, with snowfall gradually decreasing from the west.
Active aviation weather period this evening, freezing drizzle will continue for the first 2 to 3 hours of the period across central Oklahoma, impacting both KOKC AND KOUN. With south winds increasing overnight, temperatures will steadily climb back above freezing across the region, with drizzle and MVFR fog remaining possible. Freezing drizzle may develop later tonight at KPNC as well, as moisture increases. Kept temperatures in north central Oklahoma a bit cooler to account for lingering cloud cover. This warmth will not last long, however, as a cold front rushes in on Saturday. Kept wind speeds above guidance for Friday and Saturday as model blends look to be washing out the higher speeds. Kept timing on the faster side of guidance for the incoming cold front.
Low pressure will bring a wintry mix of snow, freezing rain, and rain to the region tonight through Saturday night. A brief push of warmer air will accompany this system with temperatures pushing into the 30s to low 40s on Saturday.
First off, all models are in decent agreement in deepening a sfc lee trof on Friday. Attention then turns to a strong arctic cold front which will deliver the coldest air to the region so far this season. Have sped it up just a bit over the models due to past history with these arctic cold frontal boundaries.
Gusty northwest winds will follow the frontal passage as temperatures drop below freezing behind the front. Less certain with the Western Magic Valley which will see rain change to snow around 14Z Friday morning, but having been warmer expect it to take longer to see ice and snow accumulation. Otherwise have added patchy dense fog to the forecast for this evening into early Friday morning for the lower Snake Plain. Snow levels 3-4k ft north and 6k-7k ft msl along the Nevada border at 06z lowering to the valley floors by 12z following a cold front.
Most of the very light precip is not making it to the lower 1k to 2k feet above the ground level. There will be the potential for some very light drizzle or freezing drizzle this morning over the western half of the area into central Missouri as the lower atmosphere tries to saturate. A low pressure area will develop this morning across Kansas and move eastward today. Temperatures may be in the 50s across south central Missouri around daybreak while it may be in the low 30s across west central Missouri into southeast Kansas.
Further south, moisture remnants from yesterday's warm front will keep a threat for flurries or brief light snow across SE WA and lower Idaho Panhandle with the potential for up to an inch of light and fluffy accumulations.
419 AM EST Fri Dec 16 2016 Today-Tonight: Frontal boundary has moved into the Florida Straits early this morning, leaving a slightly cooler and drier, though still above normal, atmosphere across South Florida.
First, Freezing drizzle on Friday into Friday evening that will likely result in travel problems.
Visibilities are down to 2 to 3 miles under this snow band (once the low levels can saturate) and we could pick up a half inch from this. Snow should then increase from the northwest mid to late morning as the main trough and cold front approach. Northwest winds will likely be breezy by later Saturday into Sun morning behind the cold front.
The hemispheric view shows a wave number of 3 around the globe with two strong blocking highs over the Pacific Ocean and Western Europe. west coast as a long wave trough now over the area will move off to the east Friday. The highs Friday will be 5 to 10 degrees below normal over most of the area. The lows Friday night will be below freezing everywhere but most of the immediate coast.
The early morning freezing drizzle should give way to drizzle as temperatures will warm up enough to prevent freezing. With temperatures so cold, the dendritic growth zone is very low making the low and mid level moisture plume enough to produce snow but is likely to be preceded by a short period of freezing drizzle. Fortunately, the trough associated with the frontogenesis is progressive and will not hang around long. This fast moving trough and frontogenesis will prevent significant snows from occurring.
447 AM EST Fri Dec 16 2016 A wintry mix of precipitation is expected with weekend low pressure. The overall setup would indicate snow late this evening then a slow change over to freezing rain from south to north overnight. Eventually, the ground will warm and freezing rain will change over to just plain rain on Saturday. It should be noted that even though thermometers readings will go above freezing, this does not represent what ground temperatures are. So for the forecast, did not indicate a change over to rain once model data indicated a rise above 32 degrees, but held on to freezing rain until temperatures rose closer to 35. So this will eventually allow for a much warmer day Saturday, compared to temperatures of the past week.
but remain mainly south of the Highway 200 corridor. As the low strengthens, winds will shift to the northeast and usher in the cold, dry airmass across western Ontario.
These low/mid clouds will be sticking around through tomorrow afternoon (perhaps along with a few stray showers) as the warm front moves inland from the Gulf.
Low level flow should continue to veer around to the southwest overnight which will result in the lower cloud deck to advance eastward. Ceilings heights with the lower deck are just a few hundred feet above MVFR categories but should be slowly lowering overnight as they advance eastward. Meanwhile, the stratus deck is tough to follow under the high clouds, but obs of ceiling height show it to be following the late afternoon trend in clearing line working to the NW into NE TX.
18z models and 00Z NAM continue to show a strong cold front with origins in the Canadian Yukon and Arctic will plow through South Central Texas Saturday evening.
High pressure will be North of the region Today, with an inverted coastal trough developing. The trough will produce enough convergence to provide the chance for a few coastal showers this afternoon. The trough will weaken Tonight as high pressure builds to the East. We begin the period with a zonal upper level flow across the southern tier of states with a short wave trough digging into the upper Great Plains by Saturday night. At the surface, a ridge will have shifted well offshore with a southerly flow across the area and offshore waters. A few showers will develop over the eastern coastal waters in the periphery of the ridge.
Latest hourly MOS Guidance is also showing warmer temperatures overnight and updated forecast to reflect warmer readings and increased cloud cover. Latest hourly MOS Guidance is also showing warmer temperatures overnight and updated forecast to reflect warmer readings and increased cloud cover.
Water vapor loop shows a positively tilted trough digging into the northwestern CONUS and this should move into the Northern Rockies by late afternoon. Arctic air will begin to sink into the northern counties this afternoon as high pressure starts to build into the area.
and light rain or drizzle continuing to develop as a weak coastal trough across the lower Texas coast provides overrunning conditions. Expect MVFR conditions to prevail this evening before IFR conditions develop late tonight into early Friday morning as a weak coastal low develops along the lower Texas coast/northeast Mexican coast allowing lower ceilings to develop as well as reduced visibilities with mist/light drizzle. With weak surface coastal troughing and overrunning, coverage should continue into the evening hours across mainly the Lower Rio Grande Valley as 850mb winds out of the south increase tonight atop northerly winds at the surface.
419 AM EST Fri Dec 16 2016 A wintry mix of precipitation is expected with weekend low pressure. The overall setup would indicate snow late this evening then a slow change over to freezing rain from south to north overnight. Eventually, the ground will warm and freezing rain will change over to just plain rain on Saturday. It should be noted that even though thermometers readings will go above freezing, this does not represent what ground temperatures are. So for the forecast, did not indicate a change over to rain once model data indicated a rise above 32 degrees, but held on to freezing rain until temperatures rose closer to 35. So this will eventually allow for a much warmer day Saturday, compared to temperatures of the past week.
Temperatures will steadily rise through the day and into the night ahead of the arctic cold front which will push into far NE OK around midnight. A narrow zone of rather strong lift will develop with precip spreading from the High Plains eastward. An initial onset of sleet and snow mix will transition to light snow with the highest chances for measurable snow currently appearing toward the OK/KS border and points northward.
High pressure is building across the eastern United States centered on the Great Lakes. A large upper level low is moving northeastward over the Canadian Maritimes while an upper ridge over old Mexico is building northward across the Intermountain West.
255 AM MST Fri Dec 16 2016 Warm front currently located across northeast Colorado will sag southward today. The far southwestern part of the forecast area will be on the warm side of the front and temperatures could briefly reach the lower 60s, but most of the area will be on the cold side where highs will be in the 20s and 30s.
Strong high pressure will then settle in over the region, bringing bitterly cold temperatures and wind chills with it.
Highs will be in the mid-upper 70s and lows tonight mostly in the lower-mid 60s. Stratocumulus does not look real extensive over the Atlantic yet, and with the initial dryness in the low levels, expect partly sunny skies, though a few mostly cloudy periods are possible along the coast. late week zonal pattern aloft transitions to southwest flow between anticyclone east of the NE Bahamas and evolving, broad long wave trough stretching from the Great Lakes to the Desert Southwest. broad upper trough flattens and moves from midwest toward eastern seaboard. 75 inch) precipitable water sets up quasi-stationary from the lower Gulf to central peninsula Mon- Wed as surface boundary reaches CWA, stalls and gradually loses identify as upper support wanes. Shallow northerly flow gradually bridges the weakening boundary. Scattered showers through the period as frontal trough stalls.
1039 PM MST Thu Dec 15 2016 Upper level analysis has broad trof across the east with broad ridge across the west. Another trof is diving south off the coast of BC. At the surface, arctic high resides across the Northern Plains and Midwest, with weak low pressure across the central and northern Rockies. Deep arctic trough will remain in place over central Canada through the weekend.
Temperatures will climb well above normal for this time of year, with highs ranging from the lower 70s along the I-10 corridor, to the upper 70s across the Big Country.