Aikyam-Lab/Synoptic-Bench huggingface dataset:
The increase in rain chances and cloud cover will keep the northwest areas cooler, with highs in the mid 70s versus low to mid 80s in the southeast today and Wednesday. Upper level flow across the central United States will remain southwesterly on Wednesday, but upper ridging over the southeast US will build to the west into Arkansas.
1224 PM EDT Tue Oct 3 2017 High pressure will cross the region today then move south tonight. A cold front will cross the region Wednesday night.
528 AM MDT Tue Oct 3 2017 Line of showers and thunderstorms along the cold front will exit the forecast area by 12z. Satellite however shows the low clouds lingering well behind the front, and latest HRRR shows a slow north to south progression of the clouds today.
704 AM EDT Tue Oct 3 2017 VFR conditions expected throughout the forecast period with high pressure remaining in control of the weather pattern over the eastern US.
737 AM EDT Tue Oct 3 2017 High pressure over northern New England will bring moderating temperatures and mainly dry weather for the next several days.
Dry and stable conditions expected today as a 5950 meter 500mb ridge builds over the area. This strong of a ridge would normally bring much above normal temperatures to the area, but a cooler low level easterly flow will temper afternoon temperatures. Temperatures will be much warmer than yesterday, with highs today in the lower to middle 80s.
Mostly clear skies prevail across much of interior Northern California, save for a few mid-level clouds associated with a closed upper level low over the region. Temperatures plummeted last night in wind-sheltered areas and under the cold airmass, with some locations dropping into the lower 40s across the Valley. As the upper low slowly shifts eastward today, a few snow showers are likely to develop over the higher elevations of the northern Sierra this afternoon.
Freeze Warning for the Western Magic Valley was allowed to expire as temperatures have climbed above freezing. Upper low will be to our southwest so forecast still looks dry for today. Upper trough over the interior west will close off a low in ne Calif/wrn Nevada today. Clouds and pcpn will moderate diurnal temperatures on the Idaho side with milder lows tonight and cooler highs Wednesday.
Overall, favored the 10 UTC NBM for most fields for the remainder of the day given its stronger wind solution southwest per observed trends this morning and cooler highs for the day. The main concerns in the Short Term are precipitation chances today, then the potential for freezing temperatures southwest tonight.
The clouds and showers will also help hold temperatures down, and have lowered afternoon highs a few degrees in most areas, 08z/3am surface analysis shows sprawling ridge of high pressure extending from Maine to the Gulf Coast. Temperatures will likely be a few degrees cooler than yesterday though. Given the cloud cover, highs today will generally remain in the lower 80s.
609 AM CDT Tue Oct 3 2017 MVFR ceilings at all terminals to begin the 12Z TAF cycle with a cold front dropping into the Oklahoma Panhandle. There could be a brief drop in ceilings behind the cold front but think they will recover quickly. The cold front is expected to move through KGUY and KDHT between 12Z and 13Z. Convection will also be a concern once the cold front moves through with all terminal having prevailing thunder from 00Z onward. An upper high to the east of the Panhandles and a closed upper low over the Great Basin region will allow for an active southwesterly flow pattern aloft today through the middle of this week.
Coupled with a stable atmosphere underneath a mid-level ridge, rain is not expected.
Rain showers and a few thunderstorms will accompany a cold front tonight into Wednesday.
Light additional amounts are expected from Great Falls to Lewistown, with favored upslope areas from Augusta to Cascade to Raynesford seeing the highest amounts. High pressure building in tonight will allow generally light winds beneath mostly clear skies. On Wednesday, a mid-level warm front will move north, bringing another chance of rain/snow to Southwest Montana and southern sections of Central Montana with light accumulations possible.
For 12z Aviation discussion below The axis of heavy rainfall set up from a Redwood Falls to Buffalo to Cambridge line overnight.
524 AM MDT Tue Oct 3 2017 Positive tilted trough extending from southern Canada, southwest towards the southwest CONUS.
Have allowed the Freeze Warning to Expire at 10 AM MDT as temperatures have warmed above Freezing for nearly all of the Arco Desert, Eastern Magic Valley and Snake Plain. Upper low will still cut off around Reno this afternoon, while the other upper circulation in eastern Montana loses its wrap-around influence to our Central Mountains.
641 AM CDT Tue Oct 3 2017 Forecast concerns will be ongoing showers and thunderstorms and temperatures/winds at the cold front slowly slides southeast.
Daytime heating, with highs rising into the lower 80s may result with a few fair weather cumulus this afternoon. Short range models indicate the 5h ridge positions will bridge itself further west into TX by Wed-Thu.
945 AM PDT Tue Oct 3 2017 A deep trough over the West will bring another cooler than average day today with a deep marine layer west of the mountains.
will continue to ridge south southwest into the Gulf of Mexico with the breezy east to northeast flow persisting.
/issued 349 AM CDT Tue Oct 3 2017/ SHORT TERM (Today through Wednesday): Deeper moisture profile building inland this morning, as the inverted midlevel trough sweeps inland. The midlevel trough drifts west tomorrow, taking some of the instability, but moisture remains, along with daytime heating and negligible cap, will produce more showers and thunderstorms.
931 AM MDT Tue Oct 3 2017 Fog is lifting/has lifted across the area while most temperatures have reached above freezing.
Winds are southeast at 5 to 15 mph with temperatures ranging from the mid 60s in the east to warmer low 70s west.
1222 PM EDT Tue Oct 3 2017 High pressure extending into the area from the northeast will shift slowly to the east over the next few days. Upper level ridge axis remains just to the north and west of the area. Temperatures rising into the lower 80s most locations.
1102 AM EDT Tue Oct 3 2017 Onshore winds will increase some today as the local pressure gradient tightens between strong high pressure to our north and a weak tropical wave to our south. Small craft advisory conditions continue due to long fetch of onshore winds with strong high pressure north of the area.
This activity will continue to move towards the coast, helped by the passage of an inverted trough and a huge plume of Gulf moisture. Some drying across the east is expected as mid-level ridging begins to build in from the east.
1049 AM EDT Tue Oct 3 2017 High pressure over northern New England will bring moderating temperatures and mainly dry weather for the next several days.
WV imagery indicates a positively tilted upper level trough of low pressure situated across the Intermountain West while a southwest flow aloft prevails across the Western High Plains. Near the surface, a slow advancing cold front extends from north central Kansas southwest into the Oklahoma Panhandle. A strong cold front was rolling across central and southwest Kansas early this morning. Cloudy and much cooler weather will be spreading into western Kansas today behind the front. The frontal boundary will be lifting north as upper level high pressure over the lower Mississippi Valley retrogrades westward into the southern Plains.
So widespread freezing temperatures are still expected to occur, dropping to the lower 20s by Wednesday morning.
Expect temperatures to increase into the lower 50s by midday with increasing subsidence from WSW flow aloft. There is a strong southwest flow aloft across Colorado today with one exiting upper low entering the Dakotas while another low is forming over Northern California. Temperatures will be a little warmer today with more sunshine expected, especially over northern sections and readings expected to be in the mid to upper 50s. A disturbance in the southwesterly flow aloft on Wednesday, combined with moisture southeasterly surface flow will bring warmer temperatures and scattered showers. A few thunderstorms are possible in the afternoon over the high terrain, then as the wave passes further east, a few weak thunderstorms may push northeast over the plains during the early evening.
Weak cold advection and a pressure gradient suggests that I lean towards the higher end of guidance with gusts around 30mph across northwestern counties. The center of the high will move into western South Dakota tonight with a ridge axis that extends to the southeast. The rest of the forecast is dry as the high moves due east.
1035 AM EDT Tue Oct 3 2017 High pressure will remain overhead through Wednesday.
1240 PM EDT Tue Oct 3 2017 High pressure will maintain dry and warm weather through Wednesday.
831 AM EDT Tue Oct 3 2017 High pressure will maintain dry and warm weather through Wednesday.
744 AM EDT Tue Oct 3 2017 High pressure extending into the area from the northeast will shift slowly to the east over the next few days. Upper ridge axis just to our N and W, stretching from the Gulf Coast NE into the Central Apps. Some upper impulses rotating clockwise around the E periphery of the ridge progged to shift SW along the coastal Carolinas. Will continue to trend on the high side of guidance on max temps based on recent observed biases.
947 AM EDT Tue Oct 3 2017 High pressure will cross the region today then move south tonight. A cold front will cross the region Wednesday night.
Inverted trough will move to the west into Mexico underneath the Subtropical Ridge centered from the Ohio Valley to lower Mississippi Valley. The Subtropical Ridge shifts to the west and becomes centered over Texas on Wednesday. The deeper moisture lingers over our area, however, a slight drying begins across the Highway 77 corridor.
Some of the early morning convection along the cold front across western Kansas may push into western parts of central Kansas before waning somewhat after sunrise. The cold front will move slowly east across central Kansas during the day with renewed convection expected along the front this afternoon. The frontal boundary looks to become quasi- stationary near the Oklahoma border on Wednesday with upper ridging progged across the area.
1111 AM EDT Tue Oct 3 2017 An upper level ridge centered over the western Gulf of Mexico reaches well to the northeast past the Great Lakes. The surface anticyclone centered over the northeastern United States happily stretches to the southwest beneath the mean layered ridge. Winds across the Florida Keys have responded to the tightened gradient along the southern flank of the anticyclone. The high tides of October and November are usually the highest predicted tides of the year.
High pressure remains anchored over the Mid Atlantic region, providing another day of mild sunny weather for our area.
and Wednesday A weak cold front in Minnesota will be slow to move east today due to southwest upper flow and a surface wave moving northeast along it. Despite the passage of the cold front, highs will still be 5 to 10 degrees above normal.
1042 AM EDT Tue Oct 3 2017 High pressure in control through mid week. The upper ridge axis will shift to the east coast tonight.
The main exception to this appears to favor the SW Panhandle where a cold front is progged to stall this afternoon and serve as some impetus for precip. This push of lower 70 dewpoints alone is likely not enough for widespread precip development, however surface and satellite analyses are sampling an inverted trough (just offshore of the TX Gulf Coast at 3 AM) moving NW. Areas north of the Highway 70 corridor should benefit the most from the stationary front in the vicinity for at least the first half of the day, before retreating north thereafter as heights slowly build signaling the approaching subtropical high.
Improvement is forecast at KROW between 16-18Z, but conditions at KTCC will deteriorate behind a backdoor cold front about the same time.
They will be strongest beyond 10 nm from shore as a thermal trough deepens along the coast.
High pressure will settle down the Missouri River Valley late tonight and allow light winds to develop in south central SD. Tail of upper jet pulls away on Wednesday through the northern Great Lakes on Wednesday, allowing ridging aloft to become reestablished across the region.
High pressure remains situated to our east with Middle Tennessee under a warm, southerly flow. Model soundings do indicate an increase in the low-level flow, which will contribute to an increased potential for LLWS, but not strong enough to warrant mention in the TAF's.
Fairly strong high pressure still aligned along the eastern seaboard with a tight pressure gradient in place.
A cool upper trough will remain across the northern and western Great Basin through mid week. Cold upper trough developing over western Nevada and northern California this morning will consolidate into a closed low by this evening and move east northeast across Nevada tonight.
A breezy day expected for the region today with temperatures a few degrees warmer than yesterday. Gusty, southerly winds will develop this afternoon ahead of a weak cold front with gusts in the 30 to 40 mph range likely; outside of the Las Vegas valley where gusts will remain closer to 25-30 mph.
Upper high pressure area over the southeast states will retrograde westward, becoming centered over east Texas and the lower Mississippi River region by late tonight. The high pressure areas will keep dry weather conditions across the forecast area.
Ceilings are expected to drop IFR in the evening and VCSH will become more widespread in advance of an approaching cold front. The cold front is expected to enter the region after 06Z and move SE bringing -SHRA and TEMPO TSRA during the overnight hours.
Another Pacific Northwest trough will dig into the southwest. With the increasing downslope flow, should see temperatures warm up a little more, with highs across the central and western zones getting to near freezing for highs today and above freezing for Sunday.
Automated station at Galesburg suggests a bit of sleet may still be occurring, but temperatures are above freezing and no surface impacts have been received recently. Deep trough over the southwestern portions of the country continues the southwesterly flow into the Midwest aloft. and being under the highest qpf through tonight. However, details are missing as the position of the low is still a bit amorphous with an elongated trough associated with this wave. For now, much of the forecast area is in a Marginal Risk, and the southeast in a Slight Risk, with the best chances to see some warmer temperatures.
A passing trough will bring increasing clouds, breezy westerly winds and a slight chance for snow showers along Arizona's northern border overnight.
Especially since amounts are on the lower side of expectations. Do not doubt there will be some minor drifting and refreezing though, especially across north/south roads, as winds will gust to 25 mph at times.
220 PM CST Sat Feb 24 2018 An upper trough is over the lee of the Rockies with the base of the trough over the CWA. Strong winds at the base of the trough are mixing downward towards the surface resulting in high winds in the Guadalupe Mountains. The upper trough will lift northeastward and another trough from the Pacific Northwest will move over the region on Sunday. Temperatures on Sunday are expected to be as warm or warmer than today with downslope warming taking place.
That threat will at the highest as storms move from West TN, then the threat will gradually decrease as the storms move eastward.
Should fog develop as currently forecast, keep in mind that with temps expected to fall into the 20s area-wide, this would mean the potential for freezing fog.
Severe threat will begin to increase now through early this afternoon across the Arklatex region as upper trough ejects out out onto the High Plains.
/issued 944 AM CST Sat Feb 24 2018/ A warm front currently stretches from near Batesville, Arkansas to Paducah, Kentucky this morning. Although, the best chances for severe weather will come later in the afternoon with the expected line of convection ahead of the cold front. tapering off to the low 50s in Northwest Arkansas.
24/18Z TAF CYCLE Warm front wl cont to lift NWD acrs N AR this aftn. The system will drag a cold front into the region, with widespread showers/thunderstorms ahead of the front. As the system tracks through the southern Plains, a warm front over southern sections of the state will slowly lift to the north.
339 PM CST Sat Feb 24 2018 An upper trough will push east across the Panhandles tonight and a second upper trough will track east across the forecast area Sunday.
A Pacific cold front is pushing across the southern Edwards Plateau and then over the Hill Country next hour.
The higher terrain of western Montana and north-central Idaho should see periods of moderate to heavy snow for most of the day tomorrow, with up to a foot or more of snow possible. Strong winds at the ridge tops will likely downslope much of the broader valleys, such as the Missoula/Bitterroot and Mission/Flathead Valleys for most of the day.
The main batch of precipitation will move into the area early Sunday with the main cold front and upper level trough. Chattanooga Airport, TN 77 58 65 49 / 40 80 80 50 Knoxville McGhee Tyson Airport, TN 76 58 65 48 / 40 70 90 50 Oak Ridge, TN 75 58 66 48 / 40 80 80 30 Tri Cities Airport, TN 74 56 68 46 / 40 60 80 50.
This was helping sweep out the low stratus that has been entrenched across the area for the past few days. Given the drier conditions expected in the lower/middle levels of the atmosphere, only some scattered to occasionally broken mid/high clouds are expected. Model soundings are supporting temperatures a few degrees cooler than that so did not go too overboard in raising high temperatures. We could wind up being warmer though, depending on the amount of cloud cover and magnitude of the downslope.
The winds will decrease by Sunday morning as this low exits into the Great Lakes. Sunday is expected to be dry with sunshine as subsidence sets in as the upper trough moves off to the east.
Areas of freezing drizzle look to continue through mid morning for much of Kansas as isentropic lift looks to be favorable ahead of a low pressure center in eastern New Mexico. The conditions will quickly change as a cold front will sweep the majority of the low clouds and moisture away by around noon to the mid afternoon for the region.
303 PM CST Sat Feb 24 2018 H5 analysis from earlier this morning had a broad trough of low pressure extended from eastern Montana south into western New Mexico. Downstream of the central CONUS trough, high pressure was anchored over southern Florida with a ridge extending from the southeastern states into the upper Mississippi valley. Across the Central and High Plains, a trough of low pressure extended from the western Dakotas into the Nebraska Panhandle. Guidance came in some 10 degrees warmer than what we we're previously forecasting, so will follow the lead of the guidance and push those high temperatures up. AS soon as the sun broke out today, temperatures rapidly rose into the mid 30s, which was ~5 degrees warmer than anticipated.
The main question is how much snow will the area receive today? While the upper trough is positively tilted currently, it becomes more negatively tilted as it heads into the Dakotas/Minnesota later today. The deterministic NAM looks like the high end of guidance while the GFS deterministic is a bit more modest. Omega values as the trough transitions increases to 10 to 20 microbars between 15Z and 21Z with the GFS being a tad faster which is also the reason for the lower QPF. Again, this is mainly at the 600-500mb levels with less lift in the low levels, but it still appears that this will occur over a deep dendritic growth zone, which may push up the snow ratios some.
Areas that see the clear skies and light winds will see overnight temperatures drop into the low to mid 30s. Areas to the east will see overnight temperatures in the low 40s.
A cold front extending from eastern Texas up onto Arkansas late this afternoon is expected to move east toward the forecast area tonight and drop slowly southeast across the forecast area on Sunday, roughly extending along the I-65 corridor in Alabama by the end of the day on Sunday. Cooler temperatures begin to move in from the northwest on Sunday, with highs over northwestern zones only in the 60s and 70s.
The primary short term concerns are the potential for freezing precipitation across mainly the southeastern half of the GLD forecast area in addition to the potential for brief moderate to heavy snowfall extending from Yuma county into extreme southwest Nebraska and far northwest Kansas first thing this morning as the progressive system currently moving across the region continues eastward today. A lack of good cold air advection until after the precipitation area associated with the system moves east of the forecast area means areas of fog with drizzle and freezing drizzle could continue this morning mainly across the southeastern half of the forecast area. As the upper trough and associated surface features move east of the area by early afternoon, expect the airmass over the forecast area to dry out rapidly with clearing skies expected by late afternoon.
Ridge tops generally above zero with some wind, especially around the Little Rockies. Upper flow keeps a trof over the western states for most of the week, but with flow out of the Pacific instead of the Arctic into Montana.
Morning update: Bands of moderate to heavy snow producing 1-2"/hr are impacting Southeastern WA and the lower Idaho Panhandle.
236 PM CST Sat Feb 24 2018 An upper level trough is spreading across the Plains this afternoon. Ahead of the trough large scale lift resulted in yet another round of widespread moderate to locally heavy rainfall developing across the region this morning into this afternoon. This risk will still be on the low side in south central Missouri as the better instability remains to the south.
159 PM CST Sat Feb 24 2018 Progressive clearing is expected this evening from central into eastern Kansas in the subsidence region behind the departing upper trof. Another upper trof diving southeast from the Pacific Northwest will move across the Rockies tonight and turn eastward over the Plains during Sunday.
302 PM CST Sat Feb 24 2018 After the short wave trough currently affecting the region moves east tonight, another will be hot on its heels for Sunday afternoon. A low level thermal ridge will intersect the strongest 500mb winds north of the FA in the central Panhandle.
West winds and a bit warmer Sunday. With increased sunshine for at least the first half of the week and temperatures peaking near freezing, will likely see increased snow melt.
We don't have the warm Gulf Stream nearby to produce a huge snowstorm, but there is enough moisture for six inches of snow across far northcentral Wisconsin and lesser amounts of snow mixed with sleet, freezing rain or rain elsewhere.
The system's cold front and associated steady snow has exited most of the area, with precip now mainly showery in nature. Thus the lower elevations will see mainly rain showers this afternoon. Extended models have also come into better agreement for the later portion of the week as an upper low moves through.
Another weak upper trof will cross the Northern Plains on Sunday, but main energy and precipitation remain south of the forecast area. Weak ridging moves into the area late in the day and into Sunday night. Models are showing a low pressure system developing over southern CA early in the week, but most of the energy associated with this system should stay south of the CWA.