Aikyam-Lab/Synoptic-Bench huggingface dataset:
The main story for Sunday night through the week will be troughing and more troughing with continued cool temperatures and precipitation chances. Many of those in the high country will probably remain below freezing through the week and a reinforcement of cold air will bring the chilliest air yet this season to all the U.
1148 PM CST Sat Nov 12 2022 Trying to figure out a reason why the low clouds across much of the Mid-South will clear out overnight. The 850 mb thermal trough over the region attm will slowly move east overnight as upper ridging builds into the area.
Flurries are continuing under portions of the low- level cloud deck as well, with the only area of clear skies being across south central SD at this time. Increasing southeasterly winds and high cloud cover will develop through the Sunday morning hours, as high pressure drifts further east. Freezing fog will be possible, with the highest chance over western Corson County. Elsewhere, we start to lose some of the lower level moisture after daybreak Sunday. While to low itself will be sinking south from CO to NM, a trough will extend across our area during the day Sunday. It will shift over our eastern counties Sunday night, enhanced by the 500mb trough sinking across eastern MT and through the Dakotas. The extended opens on Monday with a deep upper trough over the plains.
1045 PM CST Sat Nov 12 2022 It's a cold evening across the area with temperatures mainly sitting in the low 30s. (This afternoon through Sunday Night) Water vapor imagery this afternoon shows an upper-level trough over the Great Lakes region with drier air rounding its base pushing into TN. Much colder air is certainly in place today in the wake of last night's cold front, and temperatures at this hour are still in the 30's areawide. That aforementioned trough will exit to the NE late tonight, and cloud cover will slowly clear out, leaving behind mostly clear skies for Sunday.
Vort max at the base of the upper level trough axis will be swinging through the Ohio Valley at the start of the period. High pressure currently over the Dakotas will build in over the Ohio Valley by tomorrow. Good subsidence along with increasing heights as upper ridging develops will provide mostly sunny skies. Temperatures will be warmer than today but still 10-15 degrees below normal as highs will only top out in the low 40s. As a result, expect low temps well into the 20, with even some upper teens possible in some of the cooler spots.
1254 AM EST Sun Nov 13 2022 Cold west to northwest wind and a crossing trough of low pressure will spread scattered snow showers across the region today. The trough axis will cross the region today before high pressure and subsidence fill in late day nudging the upper level disturbance toward New England. Shower activity will thus dwindle west to east through the day, lingering longest near the I-80 corridor as NW flow on the backside of the low provides some lake enhancement. Expect clouds to increase late in the day amid warm advection aloft ahead of the next low pressure system.
High pressure begins to build over the Gulf which will send a plume of drier air over our area through the day on Monday which should lead to an even drier day than Sunday. High temperatures will run in the low-to-mid 80s through the period with nightly lows in the low-to-mid 60s.
123 AM MST Sun Nov 13 2022 Water vapor imagery shows an upper low over southern Saskatchewan dropping south to southeast into eastern Montana. This low had strong dynamics but limited moisture. As the lows drops into the area it will pull a weak cold front through and generate areas of light snow. High temperatures will be a little cooler today behind the cold front.
Meanwhile, a rapidly weakening cold front is draped from the northeastern Gulf of Mexico to the western Bay of Campeche and is indirectly responsible for maintaining a light confluent southwesterly flow through the lower levels. Short Term Update - Through the overnight period the Gulf of Mexico cold front will inch its way southeastward and will play a hand in affirming a weak prevailing northwest to northerly flow. This will be in the mid 70s, with some interior and protected locations likely able to scrub temperatures down into the lower 70s. A weakening cold front will continue to work its way southeastward through the Gulf of Mexico through the overnight period, but will remain a long ways off by morning.
A dusting of snowfall is possible across the higher elevations. Light snow showers across the higher elevations due to orographic lift. Due to the sharp inversion just above this shallow boundary moisture layer, the mixing out of the low-clouds will be slow and will trend toward more cloudiness today.
A 500 mb trough extending through the lower peninsula will allow for enough upper level instability to aid snow generation through the mid to low levels. A positively tilted mid to low level trough will pivot over the Michigan Indiana border and shift the winds from north to northwest. Expect skies to slowly clear as a ridge of high pressure build in tonight into Monday morning. --Cold air will dominate the upcoming week with chances for snow-- As that high pressure build it will allow for temperatures to remain cold. The mid week will be dominated by an upper level low that breaks off and swings southward across the northern plains. Michigan will remain on the cold side of the system with much of the low to mid level flow coming from the east.
Brisk northwesterly winds are making things feel quite chilly out there at the moment with most locations already near or below the freezing mark. So with cloudy skies for much of the day (and if you're going to be outside today), bundle up as Highs will struggle to reach the lower 40s this afternoon. (Monday Night through next Sunday) Clouds and moisture rapidly increase Monday Night as the next low pressure system approaches the area.
The trough passage has also shifted the wind more toward the north above the surface which keeps scattered snow showers off Saginaw Bay just east of the terminal corridor. Some partial clearing in the wake of this wave will allow temperatures to fall into the mid to upper 20s area-wide tonight as the cold air mass assoicated with the main upper trough deepens over the area. Moderate northwest flow with gusts up to 25 knots at times over the open Lake Huron waters will remain in place through the remainder of the weekend with a fairly tight pressure gradient between high pressure across the central US and low pressure tracking up the eastern seaboard associated with the remnants of Nicole. Nearshore conditions along the Thumb will then improve heading into Monday as northwest flow weakens with building high pressure.
Very weak WAA in place with highs just a tad warmer than today, in the mid 30s to mid 40s. Despite increasing clouds on Monday, temperatures will warm up into the low to mid 40s.
355 AM EST Sun Nov 13 2022 Cold west to northwest wind and a crossing trough of low pressure will spread scattered snow showers across the region today. A trough axis will cross the region today before high pressure and subsidence fill in late day nudging the upper level disturbance toward New England. Shower activity will thus dwindle west to east through the day, lingering longest near the I-80 corridor as NW flow on the backside of the low provides some lake enhancement. Expect clouds to increase late in the day amid warm advection aloft ahead of the next low pressure system.
That process will support warmer temperatures (i. Monday and Monday night: The 12z models indicate a multi-stream trough moving through the Great Plains ahead of a vigorous upstream system digging southeast through the northern High Plains.
Heights rise (150 dm) aloft and high pressure at the surface shifts eastward, becoming centered over the Great Lakes & Ohio Valley Region. However, overnight lows will remain on the cold side with high pressure centered over the region tonight, clearing skies, and clam to light winds.
Continued NW flow aloft in the 250mb level allows for waves to translate down from NW Canada and Alaska that ride along the amplified ridge in the Gulf of Alaska.
A low pressure system will move through the forecast area this morning, resulting in increased north winds across the area and light snow showers in the southwestern Great Basin. Primary impact will be gusty north winds that will peak this morning as the cold front passes. Winds will approach Wind Advisory criteria, but locations that reach 40+ mph will be isolated in both time and location, favoring the higher terrain. Winds will subside on Monday, though breezy north winds will persist along the Colorado River Valley as the closed low moves eastward. Minor ridging will set up in its wake, but temperatures are not expected to vary much from day-to-day.
A cold front continues to push through central Florida this morning with scattered showers and a few storms expected through the morning and into the afternoon. Scattered showers and an isolated storm possible through the afternoon as a cold front pushes through the eastern gulf waters. High pressure builds into the eastern U.
328 AM MST Sun Nov 13 2022 Current surface analysis shows arctic frontal boundary remaining mostly along the lee of the Rockies into the southern Plains, with high pressure to the east and northeast of the region. Upper level analysis still has large scale trough covering a good portion of the US, with embedded systems across the intermountain west, south central Canada, and north of the Great Lakes.
Be cautious of any slick spots, especially on bridges and overpasses this morning.
Tonight, low chances for snow remain over the area with temperatures dipping to near zero in the west, a tad warmer the further east you go but still frigid.
(Today through Monday) Persistent cloud cover over Central Alabama has kept temperatures warmer than expected, and cancelled freeze warning that was in effect for this morning. Monday will be much warmer as surface winds become southeast. The next upstream short wave trough will advance quickly eastward across Texas and Louisiana on Monday, with showers entering west Alabama Monday evening.
An upper level closed low is moving south of Reno and into southern Nevada early this morning. The low will move through the Las Vegas area this morning and then across northern Arizona this afternoon and evening, before exiting tonight. Showers quickly come to an end after midnight when the trough axis tracks east into New Mexico. A cool day follows for Monday with locally breezy northerly winds in the wake of the trough passage. Cool and mostly dry conditions are looking likely through the remainder of the week as a longwave trough pattern sets up across much of the central and western U.
High pressure and drier conditions will build into the region tonight and Monday.
(Today and tonight) The upper low currently over Nevada/northern California will continue to dig southeastward towards the Four Corners region today through this evening as weak upper ridging dominates over the FA. The upper low is expected to be approaching the Texas/New Mexico state line by sunrise tomorrow morning bringing with it a cold front and the possibility for light precip possibly in the form of a wintry mix. While there will be decent lift from diffluence just ahead of the upper trough, moisture across all levels will be lacking as moisture being transported by the storm system will just be on the fringes of the FA.
Temps have dropped down into the low 20s to low 30s so far. Temps may even get near freezing in the higher terrain of the Ouachitas late Mon afternoon. a wintry mix will be possible by sunset across the higher terrain areas of WRN AR. Temps will likely only drop down to around freezing with the snowfall. and remain in the mid to upper 30s across the lower elevations and portions of central AR. with amounts over 1 inch in the highest terrain. especially in the higher terrain of the Ouachitas and Ozarks.
Of course, it will remain warmer than this past mornings temps thanks to increasing thicknesses and slight scouring of 850mb cold, but we'll see widespread 30s for lows with 20s over the northern tier to begin the period. Highs will reach into the 50s and 60s this afternoon, about a few degrees warmer areawide thanks to the return flow setup and breezier southerlies. Have upgraded the High Wind Watch to a warning for late Sunday night through Monday morning. A swift moving cold front will drive southeast out of NM on Monday AM leading to gusty W/NW winds and modest cold air advection pattern the end of the period.
Forecast Discussion: The upper air pattern remains progressive with the coldest air associated with an upper trough now over the upper MS Valley into the western Great Lakes and Ohio Valley regions. A cut off upper low is diving south into northern and central California regions. An expansive cold Canadian high pressure cell is in control over the central CONUS. Warmer temperatures are in store for today across the area as ridging builds aloft and a southerly breeze returns. Highs still well below normal topping out in the low 40s across the forecast area. Some shorter term models are trying to hint at a reinforced cold air push with the northern stream trough which leads to enhanced forcing from mid level frontogenetical forcing.
543 AM CST Sun Nov 13 2022 (Today through Monday) Persistent cloud cover over Central Alabama has kept temperatures warmer than expected, and cancelled freeze warning that was in effect for this morning. Monday will be much warmer as surface winds become southeast. The next upstream short wave trough will advance quickly eastward across Texas and Louisiana on Monday, with showers entering west Alabama Monday evening.
At the surface, an area of high pressure will move east of the region allowing weak southeasterly return flow to increase throughout the day. Highs should top out in the mid 30s to low 40s with increasing southeasterly winds keeping wind chills generally in the low to mid 20s.
As long as the low level winds are not turning towards a direction that supports some drying, the stratus will likely remain in place.
Another slightly less cold airmass has centered itself over the Canadian Shield with a weak trough reaching back out of it through southern Saskatchewan, Montana, southern Idaho, and terminates over Nevada. A large ridge has developed off the west coast running from off of California, the PacNW, and British Columbia where it terminates over the Gulf of Alaska.
Three separate areas of low pressure surround ERN Idaho this morning currently situated across the NRN Great Plains, SRN Great Basin, and Pacific Coast respectively as a ridge of high pressure further offshore in the Pacific Ocean continues to strengthen. Being on the ERN edge of this upper level ridge, broad northerly flow from WRN Canada continues leading to a prolonged period of well below normal temperatures this mid-November. The two low pressure systems to our south and west will track further away as that ridge of high pressure to our west gains strength forcing moisture up and over the region.
303 AM MST Sun Nov 13 2022 Current surface analysis shows arctic frontal boundary remaining mostly along the lee of the Rockies into the southern Plains, with high pressure to the east and northeast of the region. Upper level analysis still has large scale trough covering a good portion of the US, with embedded systems across the intermountain west, south central Canada, and north of the Great Lakes.
and Monday High pressure will build in across the western Great Lakes region today, bringing drier air into the area. High pressure will drift off to the east tonight with a cool night in store with light winds across the area.
642 AM EST Sun Nov 13 2022 Clearing skies along with much cooler and drier weather will be over the region through Monday.
732 AM EST Sun Nov 13 2022 Cold west to northwest wind and a crossing trough of low pressure will spread scattered snow showers across the region today. A trough axis will cross the region today before high pressure and subsidence fill in late day nudging the upper level disturbance toward New England. Shower activity will thus dwindle west to east through the day, lingering longest near the I-80 corridor as NW flow on the backside of the low provides some lake enhancement. Expect clouds to increase late in the day amid warm advection aloft ahead of the next low pressure system.
259 AM MST Sun Nov 13 2022 The upper ridge axis will continue to shift east into the central plains today as two systems approach Colorado later in the day. Temperatures will be slightly cooler given shallow upslope flow developing behind a weak cold front this afternoon and resulting reduction in 700mb temperatures. A positive tilted trough will arrive early Monday morning which will bring light snowfall through upslope flow.
High pressure is filling in behind an upper level low pressure system that is moving east across the Great Basin. A frost advisory is also in effect near the coast due to low temperatures falling into the low to mid 30s. Otherwise, the ECMWF and GFS show a low pressure disturbance moving south across the region during early Monday morning. Otherwise, northerly winds from 5-10 kt along the coast this afternoon will become light tonight as weak offshore flow develops across the coastal ridges and spreads west over the near-shore waters.
425 AM MST Sun Nov 13 2022 The upper ridge axis will continue to shift east into the central plains today as two systems approach Colorado later in the day. Temperatures will be slightly cooler given shallow upslope flow developing behind a weak cold front this afternoon and resulting reduction in 700mb temperatures. A positive tilted trough will arrive early Monday morning which will bring light snowfall through upslope flow.
517 AM CST Sun Nov 13 2022 (Today and tonight) The upper low currently over Nevada/northern California will continue to dig southeastward towards the Four Corners region today through this evening as weak upper ridging dominates over the FA. The upper low is expected to be approaching the Texas/New Mexico state line by sunrise tomorrow morning bringing with it a cold front and the possibility for light precip possibly in the form of a wintry mix. While there will be decent lift from diffluence just ahead of the upper trough, moisture across all levels will be lacking as moisture being transported by the storm system will just be on the fringes of the FA.
A cyclone aloft will pass east of California today, resulting in a few snow showers in the Sierra Nevada this morning.
739 AM EST Sun Nov 13 2022 Cold west to northwest wind and a crossing trough of low pressure will spread scattered snow showers across the region today. A trough axis will cross the region today before high pressure and subsidence fill in late day nudging the upper level disturbance toward New England. Shower activity will thus dwindle west to east through the day, lingering longest near the I-80 corridor as NW flow on the backside of the low provides some lake enhancement. Expect clouds to increase late in the day amid warm advection aloft ahead of the next low pressure system.
Upper low center near KTPH this morning and progged to continue a SEly track as upstream short wave ridging moves into the CWA. 24 hr changes showing cooler temperatures in the Sacramento valley attm under clearing skies and lowering dewpoints. Further south, temperatures running warmer and dewpoints higher, which could allow for some patchy mist or light fog development in the Northern San Joaquin Valley. High temperatures today expected in the lower 60s across interior NorCal with mid 60s in the Delta where downslope off the Vaca mountains will enhance surface heating.
High pressure begins to build over the Gulf which will send a plume of drier air over our area through the day on Monday which should lead to an even drier day than Sunday.
(This afternoon through Monday night) Upper trough over NV this morning swings across AZ today and into NM tonight. This trough will pass across SE NM Monday and across W TX. While this is happening a new upper low will work down the CA coast Monday and Monday night. As the trough approaches wind speeds across the mountains will increase, High Wind Warning tonight into Monday morning for the Guadalupe and Delaware Mountains. The upper trough will also push a Pacific front through the area Monday with a very gusty W to NW wind.
1050 AM CST Sun Nov 13 2022 (Today through Monday) Persistent cloud cover over Central Alabama has kept temperatures warmer than expected, and cancelled freeze warning that was in effect for this morning. Monday will be much warmer as surface winds become southeast. The next upstream short wave trough will advance quickly eastward across Texas and Louisiana on Monday, with showers entering west Alabama Monday evening.
A well defined mid and upper level low was located over SW Utah and southern NV this morning. Some snow showers were observed with the low, and these are forecast to move into NW Coconino County early this afternoon. An upper level closed low is moving south of Reno and into southern Nevada early this morning. The low will move through the Las Vegas area this morning and then across northern Arizona this afternoon and evening, before exiting tonight. Showers quickly come to an end after midnight when the trough axis tracks east into New Mexico. A cool day follows for Monday with locally breezy northerly winds in the wake of the trough passage. Cool and mostly dry conditions are looking likely through the remainder of the week as a longwave trough pattern sets up across much of the central and western U.
Monday and Monday night: Loosely phased vorticity maxima over MT and the lower-CO Valley as of early afternoon will continue east-southeast with MT disturbance tracking through the Dakotas and NE tonight and into the upper Midwest Monday. In regard to snow accumulations, latest ensemble data are consistent with prior runs in suggesting the potential for a trace on the low end to upwards of 0. 0" on the high end.
The cold and clouds will be reinforced with help from the 500mb trough currently set up from southern Manitoba through western/central ND, and northwestern SD. The trough will only slowly shift along the SD/MN border and east during the daytime hours Monday.
Mainly dry weather conditions to prevail with periods of offshore winds across the higher terrain of the interior through midweek.
Southerly winds and warm-air advection will continue overnight, thus temperatures are only expected to fall into the low 30s to upper 20s. Monday, the upper-level trough that is currently digging across the southern Rockies will phase with a clipper system that is moving across the northern Plains. Freezing temperatures will likely be present along the back side of this inverted trough. Further to the south and east, warmer air is favored to wrap in ahead of the trough. Despite increasing confidence in a banded snow event due to increasing frontogenetical forcing along the leading edge of cold air, surface temperatures will be slower to fall below freezing than the rest of the atmosphere, so initial snowfall is favored to melt with the warmer ground temperatures.
High pressure and dry/cold conditions will prevail overnight, with lows falling into the upper 20s and low 30s once again. The flow will become more southeasterly and along with warmer temperatures, moisture will begin to increase.
In the upper levels the trough over the NE states will pull out and another trough will be digging into the Plains, gradually turning the upper flow over our area more southwesterly.
On Monday with more sunshine and southeast winds, temperatures will moderate a bit with highs in the low to mid 40s. In the meantime, the deepening trough over the southwestern CONUS, will begin to lift out towards the region on Monday. Once the snow does begin to make it to the surface, surface temperatures will be at or near freezing, so will see snow accumulate on most surfaces.