Aikyam-Lab/Synoptic-Bench huggingface dataset:
Dry weather continues through the week ahead with an upper level ridge remaining parked just offshore. High pressure moving south from British Columbia and Alberta Monday night will give easterly winds into Tuesday morning.
Most locations have the chance to see some snowflakes through the end of the day, as the aforementioned trough is moving quite slowly to the east. On Monday, a clipper will move through the region, with another cold front and continued cold air advection keeping high temperatures in the upper 20s to mid 30s. Otherwise the remainder of the work week looks quiet, with high pressure moving into the Northern Plains and daytime highs generally in the 30s.
The cold front associated with this deep trough continues to progress south as well, showing a stark contrast in temperatures across the forecast area. Still expecting the central Colorado mountains to hold the highest accumulations. near a foot on the highest peaks.
Initial cold front has moved through much of the area this morning and although currently we have a relatively dry airmass in place will see a gradual increase in lower level moisture today. This may expand southward, in the form of freezing rain, toward central Oklahoma by Tuesday morning. Low level waa develops quickly during the day on Tuesday in advance of much larger trough to the west.
223 AM EDT Mon Oct 28 2019 High pressure over the Ohio Valley will build into Pennsylvania early in the upcoming workweek.
Weak ridging aloft will turn more southwesterly while SFC/LL high pressure keeps our next pending storm system well west. by Wed morning a fairly defined inverted LL trough sets up across the region, leaving a warm front cutting across our northwest. and sharp upper trough dropping out of the northwest goes through some deepening as it moves into the plains. Closed upper low even likely to develop Wed night. The plains upper low/deep trough is expected to move from the plains up into the great lakes Thu night and this will drive a cold front across and to our east by days end. deep upper troughing will slowly dampen over several days as well.
Tonight - Monday: A cold front moved through earlier in the day but the colder air is lagging behind the surface front. As the upper wave moves east, we'll lose cloud ice so there could be a transition to freezing drizzle Monday night to Tuesday morning. But temperatures will likely be 20+ degrees below normal with highs in the lower 40s expected.
1020 PM MDT Sun Oct 27 2019 An upper trough across the northern Plains through the Great Basin continues its slow eastward push.
134 AM EDT Mon Oct 28 2019 High pressure will move across the area tonight and continue off to the east on Monday. A cold front will move into the region on Tuesday and then stall. Low pressure tracking along the cold front will bring unsettled conditions for the middle of the week. This has allowed for temperatures in outlying areas to drop off fairly quickly, where temperatures have fallen into the lower to mid 40s in spots.
Snow band from west of Scottsbluff to Horse Creek and Albany that produced heavy snowfall from Rawlins to Douglas and east along the Pine Ridge earlier continued a slow drift southward. The next upper level disturbance is progged to arrive from the northwest as early as Monday night, accompanied by a closed upper level low. This indicates that this system is rapidly evolving, and common with closed low pressure systems, erratic and difficult to forecast.
There appears to be a window of 1 to 3 hours where snowfall rates could be on the higher side with strong lift collocated with the dendritic growth zone. With ground temperatures above freezing, much of the accumulation will be slushy and some of the snow will melt on contact. However, with higher rates possible at times and air temperatures falling into the upper 20s, there will probably be some slushy accumulation on road surfaces potentially leading to slippery travel in spots especially on ridge tops and colder areas over central Wisconsin.
242 AM CDT Mon Oct 28 2019 A deep upper trough will continue to dominate the pattern in the short term, keeping the Dakotas entrenched in a cold airmass. This cold air will be reinforced at the sfc as a cold front sweeps through late this afternoon. Cold air remains the story of the extended with a semi-permanent upper trough over the region through the period.
Scattered showers and potential isolated storms will be possible in the aftn and into the evening hours, as a weak warm front lifts slowly northwest tonight. This line is slightly ahead of the actual cold front, which at 18Z stretched roughly from Waycross, GA southwest to Keaton Beach, FL as seen in the tight dewpoint gradient in the surface obs. The coolest air won't make it quite into the area however, with temperatures only dipping to the low-mid 60s in SE GA and low 70s in NE FL. The stalled front will retrograde northward, returning as a warm front Monday night and keeping the area under warm, muggy conditions with scattered showers and possibly some isolated thunderstorms through around mid-week.
Much cooler temperatures are expected Tuesday. Have gone between the cooler Hi-res model temperatures and the warmer global model temperatures as expect some modification of the airmass due to it being shallow, about 1,000 feet deep, while global models keep the front north of our area.
331 AM CDT Mon Oct 28 2019 A clipper will move through the region today, with another cold front and continued cold air advection keeping high temperatures in the upper 20s to mid 30s.
1124 PM EDT Sun Oct 27 2019 High pressure over the Ohio Valley will build into Pennsylvania early in the upcoming workweek.
SREF is favoring areas generally west of I-45 and north of I-10 for the lower vsbys and don't plan on changing much from the 00z TAFs. /ISSUED 1009 PM CDT Sun Oct 27 2019/ High pressure center located over the Mississippi River Valley and lower surface pressure over southwestern Texas in response to an approaching Great Basin upper trough has veered winds onshore. The only near term caveat will be the higher probability for early Monday morning (pre-dawn) patchy fog formation across the far northern interior.
Unsettled conditions will return midweek as another low pressure system moves through the area. High pressure will ridge into the forecast area from the north today with a frontal boundary stalled offshore. Lows will be mainly in the low to mid 60s.
342 AM EDT Mon Oct 28 2019 Mid level ridging centered near the Bahamas will sprawl across FL and much of the Gulf of Mexico through Tue as a long wave trough stretches from Hudson Bay to the Great Basin. At the surface - a frontal boundary strung out from northern FL to the Yucatan Peninsular early this morning will slowly track north as a warm front - reaching the central Gulf coast late Tue. Atlantic high pressure gradually builds in across the state to the Gulf with a relaxed gradient. From Wed through Sun: The mid level ridging initially across the area is shunted southward as the long wave trough rotates into the eastern states - ushering a cold front eastward. High pressure from the Atlantic dominates through the work week with a relaxed gradient allowing afternoon sea breezes to form.
Wind shift associated with cold front has now moved into southeast OK, with light south winds across northwest Arkansas. Cold front making steady progress through NE OK this evening but is expected to slow tonight as it encounters the higher terrain of far NW AR and far SE OK.
351 AM CDT Mon Oct 28 2019 Water vapor loop indicated an upper level low over northern ALTA and was moving south at 25-30 knots. Trough will move into southern MAN this afternoon and into northwest Ontario by 00Z Wed. However the main part of the upper low will drop into the Desert Southwest with the trough extending northeast into Ontario. A cold front will move out of ALTA/SASK today and sweep across the Red River Valley this afternoon and tonight. Upper trough will will become more positive tilted Tue.
Although the high pressure center will remain well off to the west, the pressure gradient will slacken. A trough will approach the region on Monday, switching winds to a west/west southwest direction. This dry surface flow along with warm air advection justified a Monday afternoon high temperature forecast a few degrees warmer than baseline guidance. Models agree well on timing of the cold front, reaching our western CWA late monday afternoon and quickly tracking across the region Monday night into Tuesday morning.
Lows tonight are expected to range from the low teens across far western Kansas to low 20s across south central Kansas.
MA Chattanooga Airport, TN 75 53 74 58 71 / 0 10 10 50 70 Knoxville McGhee Tyson Airport, TN 74 52 75 56 72 / 0 10 10 40 60 Oak Ridge, TN 75 52 73 56 71 / 0 10 10 40 60 Tri Cities Airport, TN 74 48 73 51 71 / 0 10 10 50 60.
625 AM CDT Mon Oct 28 2019 A deep upper trough will continue to dominate the pattern in the short term, keeping the Dakotas entrenched in a cold airmass. This cold air will be reinforced at the sfc as a cold front sweeps through late this afternoon. Cold air remains the story of the extended with a semi-permanent upper trough over the region through the period.
/issued 401 AM CDT Mon Oct 28 2019/ A strong upper trough will swing across NM today lifting across the TX Panhandle this afternoon.
451 AM MDT Mon Oct 28 2019 There has been some freezing drizzle thru the night from the Pueblo area southward to around the Trinidad area. Indications are that the freezing precip should come to an end early this morning. An upper level trof will be moving across CO thru the day, and will exit the state to the east by evening.
Temperatures on Monday should climb into the middle 50s across West Texas, as the low clouds prevent deeper boundary layer mixing. Winds back (shift counterclockwise) to the north and northeast by Tuesday night in response to strengthening surface anticyclone in the Intermountain West, causing surface temperatures to drop beneath a strong temperature inversion. As temperatures plummet due to the northerly surface wind component, a potent trough will rotate into the southern Rocky Mountain region and western High Plains. This will augment the development of light precipitation within the low-levels, with vertical thermodynamic profiles supportive of freezing rain (ZR) and/or freezing drizzle.
A weather system brushing the area will bring cooler temperatures and a slight chance of showers to the White Mountains today.
Chattanooga Airport, TN 76 54 76 63 / 0 0 10 40 Knoxville McGhee Tyson Airport, TN 75 52 74 60 / 0 0 10 30 Oak Ridge, TN 75 52 75 58 / 0 0 10 30 Tri Cities Airport, TN 75 50 74 56 / 0 0 10 10.
401 AM CDT Mon Oct 28 2019 A strong upper trough will swing across NM today lifting across the TX Panhandle this afternoon.
The next cold front is entering northwest North Dakota. A clipper will move through the region today, with another cold front and continued cold air advection keeping high temperatures in the upper 20s to mid 30s.
324 AM MDT Mon Oct 28 2019 Cold front moving south this morning across the region, generating a few snow showers on the way. Upper trof will continue to drop to the southeast, with ridge folding over into western Canada through midweek.
Water vapor loop indicated an upper level low over northern ALTA and was moving south at 25-30 knots. Trough will move into southern MAN this afternoon and into northwest Ontario by 00Z Wed. However the main part of the upper low will drop into the Desert Southwest with the trough extending northeast into Ontario. A cold front will move out of ALTA/SASK today and sweep across the Red River Valley this afternoon and tonight. Upper trough will will become more positive tilted Tue.
Surface analysis showing a ridge of high pressure extending southwest through the lower Mississippi valley into the western Gulf of Mexico. Aloft, region remains under a dry southwest flow between a high pressure ridge along the eastern CONUS and a positively tilted trof from the northern plains through the southwest CONUS.
428 AM MDT Mon Oct 28 2019 A broad trough covers the western and central states, with its axis stretching from Manitoba through southern CA. Meanwhile, a Canadian low will dive into the northern plains, and its associated cold front will approach the region. Behind the cold front, strong CAA and pressure rises of 3-4 mb/3 hrs will support breezy northerly winds.
857 AM CDT Mon Oct 28 2019 Light snow is continuing to move southeast just ahead of a cold front, which surface observations place in far northwestern North Dakota between Crosby and Tioga. The next cold front is entering northwest North Dakota. A clipper will move through the region today, with another cold front and continued cold air advection keeping high temperatures in the upper 20s to mid 30s.
As we go through tonight, increasing southwest flow aloft ahead of a digging western CONUS trough may help to increase low level flow sufficiently for breaking up the stratus deck.
448 AM CDT Mon Oct 28 2019 (Today and Tonight) The mean position of an upper trough today and tonight will be from central Canada southwest across the northern Plains to the Intermountain West. A wave rotating through the base of this trough (currently near the Four Corners area) will move northeast into the central Plains by late this afternoon. The shallow cold front is sagging into the southern third of our area, and is expected to stall near the I-10 corridor between 7 AM and 10 AM. After the warm day yesterday, temperatures will be considerably cooler today, most notably across the Big Country and northern Concho Valley. Forecast highs today range from the lower 50s across the northern Big Country, to 70-75 across the far southern part of our area.
1050 AM EDT Mon Oct 28 2019 High pressure will drift northeast across the Commonwealth this morning before becoming located over the New England states later today.
/issued 342 AM EDT Mon Oct 28 2019/ Mid level ridging centered near the Bahamas will sprawl across FL and much of the Gulf of Mexico through Tue as a long wave trough stretches from Hudson Bay to the Great Basin. At the surface - a frontal boundary strung out from northern FL to the Yucatan Peninsular early this morning will slowly track north as a warm front - reaching the central Gulf coast late Tue. Atlantic high pressure gradually builds in across the state to the Gulf with a relaxed gradient. From Wed through Sun: The mid level ridging initially across the area is shunted southward as the long wave trough rotates into the eastern states - ushering a cold front eastward. High pressure from the Atlantic dominates through the work week with a relaxed gradient allowing afternoon sea breezes to form.
WV imagery indicates a southwesterly flow aloft prevailing across the Western High Plains downstream of an upper level trough shifting eastward across the Four Corners Region. Near the surface, high pressure is shifting southeast across the high plains of eastern Wyoming and western Nebraska. Lows tonight are expected to range from the low teens across far western Kansas to low 20s across south central Kansas.
Associated with this trough will be an upper level jet of around 90 to 100 knots just over the middle of the FA by 18Z Monday. Just enough positive theta-e advection ahead of the trough will introduce some low level moisture for light snow in the western Oklahoma Panhandle and surrounding areas. Highs are expected to be in the mid 40s for the far southern and eastern Texas Panhandle, getting closer to at or below freezing in the northwest FA.
Improvements in ceilings this afternoon may be quickly lost tonight should the low stratus remain over the area. As we go through tonight, increasing southwest flow aloft ahead of a digging western CONUS trough may help to increase low level flow sufficiently for breaking up the stratus deck.
Gusty east-northeast ridgetop winds will relax across the region by midday.
The low level ridge axis is positioned from Vero Beach to Tampa means, as indicated by RAP analysis. North of the ridge axis (Orlando to Titusville northward) the flow is south/southwesterly, and this is the favored area for afternoon convection.
With the upper low continuing to move to the southeast the synoptic flow is weakening, and in spite of a deepening thermal trough on the coast the decrease in the synoptic winds are resulting in much lighter offshore winds this morning. The thermal trough weakens this afternoon before deepening ahead of the next system that slides down the back of the strong offshore ridge tonight into Tuesday morning. With the timing of the system the ridge humidities will be not as low overnight into Tuesday morning, but with the colder and dry air mass that move in the afternoon humidities will be in the teens for the majority of the forecast area.
310 PM CDT Mon Oct 28 2019 Large scale pattern consisting of a deep longwave trough pretty much encompassing the CONUS this afternoon. At the surface, high pressure was in control over across the central Plains. Tonight As the upper trough pushes farther east, large scale ascent will increase late this afternoon and into the early evening hours. By early this evening, max layer temps aloft will fall below freezing thus supportive for all snow.
300 PM MDT Mon Oct 28 2019 Scattered snow showers have diminished over northeast Montana ahead of the cold front from Canada. For the rest of today and overnight, temperatures will continue to drop as an upper level trough proceeds eastward.
The low ceilings will be slow to break tomorrow morning with many sites carrying MVFR into the 18z time frame and beyond.
This will drive another arctic cold front southeast and reach northwest Nebraska by Tuesday morning. The arctic front will continue southeast across western and north central Nebraska Tuesday as a potent upper low continues to Dive south to near Salt Lake City by Tuesday evening.
345 PM CDT Mon Oct 28 2019 A cold front will sink south across the cwa tonight into Tuesday morning.
Believe snowfall will begin about midnight tonight in the westerly orographic flow and dynamics east of the closed low. As the low center travels south over central UT, more dynamic uplift will spread over most of western CO and northeast UT. Light snowfall in the lower west-central CO valleys as will.
Right now valley fog looks likely to redevelop, although with the warmer start to the evening do expect it to take a bit longer to develop than last night. Once the morning fog dissipates, tomorrow should still feature quite a bit of sunshine through the high clouds and a warm afternoon.
405 PM EDT Mon Oct 28 2019 19z sfc analysis shows high pressure in control of the weather yielding sunny skies and light winds. Temperatures responded to the sunshine rising into the low to mid 70s while the dewpoints are generally in the mid 50s. Most of the energy stays off to the northwest of the area closer to the center of the trough. Enough clear skies through the night will promote a decent ridge to valley temperature split and areas of dense valley fog into Tuesday morning - but nowhere near as thick as it was this morning. High pressure slides off to the east tonight with a cold front approaching, but dying out before it gets too far into Kentucky Tuesday morning.
Considering winds are expected to be light and variable much of the night with some breaks in cloud cover possible by early Tuesday morning, look for lows generally down into the teens(F) with the lower 20s(F) still possible in south central Kansas. Expect highs up into the 30s(F) in west central and much of southwest Kansas Tuesday afternoon with the lower 40s(F) possible in south central Kansas.
In the bigger picture, WV imagery shows an upper-lvl trough moving into West Texas and Southeast New Mexico, which could bring enough lift into the area overnight from a chance of -SHRA tonight/Tue over the ern zones, exacerbated by isentropic upglide set to develop in the trough's wake. In the meantime, a secondary trough is forecast to drop out of Canada, and dig to the Four Corners by 12Z Wed. Just ahead of this feature, a strong cold front will drop into the area, w/fropa at KMAF Wed morning at around 12-13Z. A rebound attempt is made Fri, but a secondary cold front Fri night will take temps back down into the 50s/60s Sat afternoon.
Winds are increasing in the northwest behind the cold front, which surface analysis places in between Garrison and Bismarck as of 17Z. Finally starting to get some temperatures in the low 30s, but overall still a chilly, windy day. Light snow is continuing to move southeast just ahead of a cold front, which surface observations place in far northwestern North Dakota between Crosby and Tioga. The next cold front is entering northwest North Dakota. A clipper will move through the region today, with another cold front and continued cold air advection keeping high temperatures in the upper 20s to mid 30s.
357 PM EDT Mon Oct 28 2019 High pressure will move off the New England coast later today.
Most areas will struggle to reach the lower 30s, with locations in NW Iowa having potential to reach 40.
1136 AM MDT Mon Oct 28 2019 There has been some freezing drizzle thru the night from the Pueblo area southward to around the Trinidad area. Indications are that the freezing precip should come to an end early this morning. An upper level trof will be moving across CO thru the day, and will exit the state to the east by evening.
227 PM EDT Mon Oct 28 2019 High pressure will move off the New England coast later today.
There has been some freezing drizzle thru the night from the Pueblo area southward to around the Trinidad area. Indications are that the freezing precip should come to an end early this morning. An upper level trof will be moving across CO thru the day, and will exit the state to the east by evening.
402 PM EDT Mon Oct 28 2019 High pressure east of the region will continue to extend across the area into Tuesday. A cold front will track into the area Tuesday night and stall.
Patchy to areas of fog is likely develop across interior portions of the state by early morning hours as the frontal boundary analyzed north of the Interstate 4 corridor slowly advances poleward as a warm front over the next 24 hours or so. The high pressure builds off to the north providing us generally southeast flow.
Expect the low clouds to continue slowly eroding, although our westernmost counties will likely not break free of the low clouds today. Throughout the short term, we will be in broad southwesterly flow aloft as an expansive upper level trough continues to deepen over the western CONUS and an upper ridge remains centered over the southeastern U. At the surface, a weak cold front will approach the area tomorrow from the northwest, but without deeper moisture available or any noticeable lift, conditions will likely remain dry.
Not much going on today with only high cirrus streaming in from the southwest with west to southwest surface winds in advance of a low pressure area. Mid 30s to the lower 40s look good for afternoon highs. A deep upper trough will continue to dominate the pattern in the short term, keeping the Dakotas entrenched in a cold airmass. This cold air will be reinforced at the sfc as a cold front sweeps through late this afternoon. Cold air remains the story of the extended with a semi-permanent upper trough over the region through the period.
With this snow falling at night and higher snow rates (maybe up to 1 inch per hour), there will be likely some accumulation of roads despite the warmer roads.
1115 AM MDT Mon Oct 28 2019 A broad trough covers the western and central states, with its axis stretching from Manitoba through southern CA. Meanwhile, a Canadian low will dive into the northern plains, and its associated cold front will approach the region. Behind the cold front, strong CAA and pressure rises of 3-4 mb/3 hrs will support breezy northerly winds.
1024 AM CDT Mon Oct 28 2019 Shallow cold front is hung up in the higher terrain areas of southeast Oklahoma and northwest Arkansas this morning and is expected to make little progress through the day Today.