Aikyam-Lab/Synoptic-Bench huggingface dataset:
Conditions will gradually improve behind the front but expect very chilly temperatures in the low to mid teens this afternoon. As a ridge of high pressure across the western United States continues to build, the pressure gradient across the area will remain fairly tight. Tomorrow will be drier and warmer across the area.
1128 AM CST Wed Dec 6 2017 Dry and seasonably chilly weather will prevail today ahead of an reinforcing cold front. Strong cold air advection with 850 MB temperatures around minus 10 degrees Celsius will allow temperatures Thursday to only reach the lower and middle 30s.
A deep upper long wave trough over the Great Lakes will result in periodic reinforcements of cold air, which will in turn boost the lake effect.
Low pressure to the northeast and a high to the west will continue to bring a decent gradient, 925mb winds will be 30 to 35 kts and there should be good mixing.
This will keep temperatures similar to yesterday before a post frontal trough moves through the region late in the afternoon. Once the trough passes through, CAA will return. Normally, this set up would produce some snow flurries or light snow however, with continued northwest flow and very low relative humidities in the low levels, the chances for any precipitation is nearly non-existent for the short term. Thursday night, the upper level trough will transit to the east and ridging from the west will build into the region.
Combination of cold air advection and increasing cloud cover will only allow high temperatures to climb into the lower and middle 30s. At the start of the period, an upper trough dominates the eastern half of the CONUS with high amplified ridging building into the west. This ridge slowly spreads eastward over the weekend and raises temperatures.
934 AM MST Wed Dec 6 2017 Current surface analysis shows a Canadian cold front sliding south across the forecast area. Upper level analysis shows low pressure over southern Hudson Bay, with large trough covering a good portion of the US. A ridge lies along the west coast. Temps currently range from the upper teens across northwest SD to around freezing over far southwest SD. Upper level analysis has highly amplified flow with large trof across the central and eastern CONUS, and sharp ridge along the West Coast. Clipper system and associated cold front will drop south through the forecast area this morning, bringing continued light snow for much of the area, along with gusty northwest winds.
Winds are gentle from the east/southeast and temperatures along the island chain are in the lower 80s. A broad area of high surface pressure will lose influence across central Florida over the next 24 hours while a cold front sags across the northern half of the state. Confidence continues to increase as far as the timing a cold front across the Keys and surrounding waters.
Clouds with the cold front are well to our east now. After a near normal December afternoon, temperatures will mainly range through the 20s tonight with some around 30 readings in the warmer locations in the southeast. High temperatures will range the upper 20s to the lower 40s. Enjoy the day as the winds will be lighter too! Global model and ensemble guidance remains in very good agreement on the maintenance of high latitude blocking pattern featuring an amplified ridge-trough configuration over the West Coast and eastern NOAM. Finally, there appears to be multiple waves of low pressure lifting north along a western Atlantic front from late week into the early weekend timeframe, with guidance varying on specifics.
A few deeper valleys in the far east are still experiencing a bit of a split of 3 to 5 degrees compared to neighboring ridges. A reinforcing cold front is then on track to move through the state this evening/into the overnight, with little changes in the weather expected other than a continuation/slight increase in clouds across the SE portion of the CWA. This is supported by continued strong longwave troughing across the eastern conus, giving an alleyway from which cold Canadian/Arctic air can flow southward and into the Ohio Valley. The overriding theme of the period will be cold temperatures, as a deep large scale upper trough dominates the central/eastern CONUS.
Can't totally rule out some patchy spots of mixed precip as air column further cools, but overall terminal impacts will be negligible with surface temps remaining well above freezing and no frozen accumulation will occur.
The general longwave pattern remains in place for the next 7 days, with a ridge over the western CONUS and a trough over the east.
Very little additional warming south of Interstate, but mid lvl decks to slowly erode from the north this aftn as high pressure increases. /issued 323 AM CST Wed Dec 6 2017/ 700mb trough lagging behind surface boundary allowing for southwest flow in lower-levels to overrun cold airmass across the ArkLaTex. Periods of widespread rain to continue throughout the day and into tonight mainly south of interstate 20 before gradually clearing on Thursday as 700mb trough finally eases across the region. Temperatures today to climb into the low to mid 50s with overnight lows forecast to fall into the 30s.
The air mass behind this cold front is the coldest so far this season with 850 mb temperatures progged to be -7 to -11C for Thursday afternoon.
This activity should exit stage right after 00z this evening with attention then shifting to the inbound cold front that will result in a significant cooldown as Arctic air surges southward following its passage.
A large trough over the northern plains will continue to sink southward into southwest Kansas tonight. Depending on when the cloud deck erodes completely and the driest of the air moves in overnight lows could fall into the low 10s but kept it at the mid 10s at this point. Sunshine should be prevalent through the region as an area of high pressure moves in from Nebraska. As the high moves eastward through the day winds looks to pick back up especially for areas near the Colorado border. There will be a Hudson Bay low staying fairly stationary in eastern Canada with a large upper level ridge over the western half of the US.
319 PM CST Wed Dec 6 2017 Highly amplified pattern will persist through the next several days with western ridge/eastern trough in the mid/upper levels.
Will continue a mention of flurries through about mid-morning across the northern CWA, until this trough passes. Several of the high-resolution models eke out some light precipitation with this feature, though the period of deeper moisture is fairly limited. Temperatures today should be a tad cooler than yesterday, with 40s likely south of I-72.
A cold front pushing through will maintain northerly surface winds with some gusts this afternoon and near the end of this forecast period.
A cool and breezy day is expected as high pressure builds across the region. Light snow across southwest North Dakota will continue to diminish this morning as high pressure moves in.
957 AM MST Wed Dec 6 2017 Minimal changes to latest forecast as a deep trough remains over the eastern half of the country while a large ridge has set up over the West Coast. The anomalous NOAM Left Coast ridge will shift just enough inland late in the week that any cold air dropping down the backside will be directed well to our east.
High pressure will remain over the region for the next few days. Amplified ridge in the mid/upper levels will remain well anchored over the west coast. The lower levels remain relatively dry with this ridge aloft. For the San Joaquin Valley, this means daytime highs mainly in the middle to upper 60s with overnight lows in the lower to middle 30s.
While surface temperatures will struggle to fall due to an extensive cloud shield over the region, they will come very close to the freezing threshold across western Val Verde, much of Edwards and Real counties, and into Gillespie and Kerr counties. Regardless, with surface temperatures likely to hover at or just above freezing for these areas, and still quite a bit above freezing elsewhere, little to no accumulations are expected. Perhaps more of a concern is any standing water due to today's rainfall activity freezing on bridges and overpasses where temperatures will be the coldest, again in the Hill Country and Plateau areas.
Southwest Kansas was in between two upper tropospheric jets, with the southern jet extending from Baja California through New Mexico into the Lower Mississippi Valley.
Temperatures have stayed mainly above freezing, with the exception of the Guadalupe Mountains where temperatures have dropped below freezing with light snow this afternoon. Soundings indicate a transition to all snow in the mountains, and I-10/I-20 split, by late afternoon which will aid temperatures dropping below freezing in these areas. Precipitation amounts over Southeast New Mexico and the Permian Basin will be lighter, so even if rain changes completely to snow, surface temperatures will stay above freezing, so little accumulation is expected. Although much of the Permian Basin and Southeast New Mexico Plains will see a rain/snow mix, or all snow, overnight, surface temperatures mainly above freezing, along with lighter precipitation amounts, will limit accumulations to an inch or less.
Thursday will be a much colder day with continued CAA as the main trough moves through. Highs will struggle to reach freezing across the area.
Few changes are expected to the general weather pattern over the short term period, with a NW flow continuing through the lower levels (below ~750 mb), and a W-SW flow at and above 700 mb that will continue to keep broken to overcast midlevel clouds overhead. We will have a cold front that is currently across northern IL/IN and MI that will be moving into our area late tomorrow, but it will have very little impact this period other than a shift of surface winds to N and perhaps an increase in low clouds late in the day. With temperature advection ahead of the front being near neutral and mid/high clouds perhaps being a little thinner, Thursday's high temps should be warmer than today, mainly in the mid to upper 40s.
Northerly winds will remain between 10 to 15 knots, with the higher gusts near the coast.
Although clouds are expected to diminish this afternoon, temps will be limited to the lower 40s for highs over south central KY. Deep and vertically stacked low pressure will move across James Bay today, but broad cyclonic circulation extends well into the Ohio and Mississippi Valleys.
From tonight through Thursday, a dry cold front will bring a round of below normal temperatures and strong northeast winds to locations along and southwest of the Mogollon Rim.
An area of low pressure over MN embedded in northerly flow aloft is helping to generate some scattered flurries over the northeast corner of the South Dakota over into west central MN. North to northwesterly flow remains at 500mb, with a large trough extending from north central Canada through Hudson Bay, the Great Lakes, and into the south central U. At the same time a high amplitude ridge is over the western U.
/issued 310 AM CST Wed Dec 6 2017/ A filling mid level low was located across the desert SW within a dampening mid level trof axis. East of the trof axis zonal flow has tapped into a fetch of Pacific mstr while an embedded 3h jet of 100-110kt moves across the area this morning. Meanwhile at the surface an anticyclone will be in place across the PB today. Mid/upper level lift with Pacific mstr is enough to generate -RA this morning which will serve to moisten up/cool the low levels (which were very dry as of this writing). To further complicate the forecast there will be a shrtwv trof in the nw flow moving thru the 4 Corners region around 06Z/Thur which will renew lift/mstr and potential for SN thru the day on Thur, especially across the mtns.
A weak cold front will continue to push southward across Nebraska for the remainder of Wednesday. Highs only rise into the low to mid 30s on Thursday with lows tonight dropping into the upper single digits and low teens (warmest temperatures across southwest Nebraska).
High pressure continues to strengthen along the west coast, leading to a dry northerly flow over western Montana and central Idaho.
Strong high pressure centered to the west of Utah will maintain a stable northerly flow across the Great Basin through the end of the week. With building heights under a ridge of high pressure to the west, the big weather concern over the next few days will be the developing inversion.
Rather chilly conditions will hold over the CWA today through Thursday as the area remains under northerly upper flow between a positively tilted upper trough from the Great Lakes area southwestward and a narrow upper ridge over the far western CONUS.
345 PM CST Wed Dec 6 2017 Wx map shows cold high pressure continuing to build south across the region, providing fairly strong offshore flow with marine warnings issued. Radar showing Surface temperatures are expected to remain above freezing, so no accumulation of frozen precipitation is expected this afternoon or overnight across the region.
Issued by National Weather Service GRAND RAPIDS MI 351 PM EST Wed Dec 6 2017 Water vapor imagery shows a couple features of note rotating around the broader upper low centered just south of Hudson Bay. An even stronger PV max has entered IA as part of a broader area of enhanced PV rotating around the low.
1119 AM MST Wed Dec 6 2017 Current surface analysis shows a Canadian cold front sliding south across the forecast area. Upper level analysis shows low pressure over southern Hudson Bay, with large trough covering a good portion of the US. A ridge lies along the west coast. Temps currently range from the upper teens across northwest SD to around freezing over far southwest SD. Upper level analysis has highly amplified flow with large trof across the central and eastern CONUS, and sharp ridge along the West Coast. Clipper system and associated cold front will drop south through the forecast area this morning, bringing continued light snow for much of the area, along with gusty northwest winds.
218 PM CST Wed Dec 6 2017 Current water vapor imagery showing the upper trough beginning to drop southeast across the cwa. The longer term concerns remain the eastern CONUS trough and timing and strength of resultant short waves rotating around the Hudson Bay circulation. Initially we have a weak trough dropping southeast over the region into Thursday night.
After lows in the 20s tonight, readings on Thursday will struggle to top freezing over portions of southern IL/sw IN.
This moisture plume is located south of a broad mid- level trough axis and is associated with a stout ULJ. Where the heavier precipitation aloft lingers longer it has been able to gradually moisten the lower-levels, like at O'Donnell where the WTM has recently measured 0. Thankfully though with surface temperatures generally above freezing we don't anticipate any big problems on the roadways unless a heavier snow band lingers in one spot, which appears unlikely at this time. The upper trough axis and better lift is forecast to sag southward through the day. Outside of the precipitation chances, it will remain cool today, with highs into the lower 40s across the southern zones, where clouds will be thickest and precipitation chances highest.
with the cold front. The longwave trough pushes through the Ohio River Valley with rising heights over the Plains.
Main concerns for today and tonight are the amounts and location of snow especially across the higher elevations of Crockett County, the nearby Edwards Plateau and north towards Mertzon. Although MOS guidance continues to warm the temps into the mid and upper 30s today, it should be cold enough at the surface for snow especially in the higher elevations. According to WPC, snowfall amounts should be around an inch in the higher elevations of the Northern Edwards Plateau that include Ozona, Eldorado and Sonora.
Northerly flow aloft is still in control, but the west coast ridge of high pressure starts to nudge it's way ever so slightly eastward, cutting off all chances of precipitation here through the remainder of the week.
Even though temperatures are above freezing, wetbulb temperatures fall below freezing just above the surface. Little recovery is expected during the day with temperatures likely staying below freezing during the afternoon for most folks.
This may also be reflected in a southward moving cold front that will re enforce the modified arctic air mass currently in place. If any precipitation is able to form it will encounter relatively dry surface air and temps in the lower 40s so would expect the main precip type to be sprinkles. By late week, the strong mid-level trough will still be stretched across the eastern U. As a result, expect the coldest conditions Thursday and Thursday night with highs only reaching near the freezing mark and overnight lows plunging into the teens.
1041 AM MST Wed Dec 6 2017 Rather chilly conditions will hold over the CWA today through Thursday as the area remains under northerly upper flow between a positively tilted upper trough from the Great Lakes area southwestward and a narrow upper ridge over the far western CONUS.
Cold front is now exiting Sullivan County NY-Pike County PA after having gone through the remainder of the area. Amplified upper trough is overtaking the Midwest through Northeast, marking the change to our cooler pattern. Embedded within that trough, a weak wave will pass through this evening.
A high amplitude upper level ridge is over the western U. The axis of this ridge runs along 127W longitude. This ridge still looks to be on track to remain strong, but to shift to a position near 124W by Thursday morning. The fog in the lower Columbia Basin will decrease and lift, but will probably not completely dissipate.
Clouds with the cold front are well to our east now. After a near normal December afternoon, temperatures will mainly range through the 20s tonight with some around 30 readings in the warmer locations in the southeast. High temperatures will range the upper 20s to the lower 40s.
Deep and vertically stacked low pressure will move across James Bay today, but broad cyclonic circulation extends well into the Ohio and Mississippi Valleys.
Upper air analysis last evening showed a broad trough across most of the country with nearly zonal flow over Texas. At the surface, the cold front has moved off the coast. The upper level trough axis will swing down into the southern plains during this period. As the trough swings southward it will bring colder mid-level air into the region and a chance for a mix of rain and snow across our northern area starting this afternoon and continuing through Thursday morning. Surface temperatures will stay mainly above freezing so we don't expect any accumulation. However, some parts of northern Edwards county may get down to freezing and a dusting of snow is possible.
A large trough over the northern plains will continue to sink southward into southwest Kansas tonight. Depending on when the cloud deck erodes completely and the driest of the air moves in overnight lows could fall into the low 10s but kept it at the mid 10s at this point. Sunshine should be prevalent through the region as an area of high pressure moves in from Nebraska. As the high moves eastward through the day winds looks to pick back up especially for areas near the Colorado border.
250 PM MST Wed Dec 6 2017 This evening, isolated to scattered snow showers will occur along the higher north facing slopes, with accumulations up to 2. Lows tonight are forecast to be cooler due to cold air advection. Thursday afternoon there will be another surge of moisture bringing show to the high country and a isolated to scatter snow showers to the plains. A strengthening ridge over the western CONUS with a trough over the east will continue to bring NNW flow over Colorado. For Thursday evening the upper jet will be over the eastern portions of the state with the exiting trough over NM.
345 PM EST Wed Dec 6 2017 The pattern across the region will start to change on Thursday as high pressure continues to move away from the region. At the same time, an amplifying mid level trough will continue to dig further southward and it will send a cold front towards Florida during the next few days. This will help to begin to increase the low level moisture in the area during the day on Thursday and into Thursday night.
220 PM CST Wed Dec 6 2017 The upper level pattern will continue to be dominated by a trough over the eastern U. with a ridge over the western U. A short wave trough will occasionally move down the back side of the eastern U. trough and across the Panhandles through this forecast. One such short wave trough will move across the region on Thursday. Another shot of colder air will move into the region in association with this trough. A few flurries can not be ruled out tonight into Thursday with this system, but at this point it looks like the lower layers of the atmosphere will be too dry to allow many flakes to make it to the ground, so will leave the mention of them out of this forecast.
318 AM EDT Sun Jul 9 2017 High pressure will build into the area today bringing dry and sunny weather.
1203 AM CDT Sun Jul 9 2017 Increasing heat and humidity are on tap for the week ahead as upper-level ridging builds eastward and the thermal ridge axis bulges into the central and then eastern Plains. As such, the highest potential for storms throughout the week will be in northeast Missouri where storms that form across NE/IA are most likely to trek, but still can't rule out propagation into areas further west like the KC metro, especially toward the end of the work week as the upper flow amplifies again to the west. Slightly cooler conditions look possible this weekend when the ridge re-strengthens to the west and northwest flow redevelops, but again will be a waiting game to see whether or not this change in the pattern occurs and how long it takes to arrive.
The western extent of the Bermuda Ridge extended across the southern Gulf of Mexico- with a weakness in the ridge over the eastern Gulf. Our forecast area was south of the base of an upper trough, with the Q-G forcing associated with this trough to our north. The upper level trough will remain over the area as a cold front edges closer to the region. The low level ridge axis will remain south of the areas providing a favorable flow regime for sea-breeze induced convective coverage. Max temperatures will be near normal in the lower 90s, although many will get some relief in the afternoon from thunderstorm outflow.
Those boundaries will probably be enough to initiate widely scattered thunderstorms, with minimal support aloft under a strengthening ridge. A broad southwesterly flow will be in place in the low levels, resulting in considerable drying. Downsloping wind component and strengthening ridge aloft will result in temperatures warming into the upper 90s to lower 100s.
A short wave trough coming over the western upper level ridge will ride southeast into the eastern part of our region into Sunday evening. At the surface, a low pressure area/trough and cool front will be pushing into our region. Until then, conditions should be ideal for a big warm up on Sunday with all models showing 925h temperatures rising into the lower to mid 30s C across central and north central South Dakota. The low will shift to our southeast at or shortly after midnight Sunday night, with high pressure building across the forecast area Monday and into eastern SD and MN Monday evening.
424 AM EDT Sun Jul 9 2017 Cold front which moved into the area last evening will remain across the this morning and stall across the southern Midlands this afternoon. Satellite imagery currently shows cloudiness over the eastern Midlands with surface obs showing the weak cold front stretched across the central Midlands and CSRA. The weak cold front will move very slowly southward through early afternoon then stall across the southern Midlands and CSRA.
we'll call it "less hot" side of the boundary with highs in the lower 90s.