Aikyam-Lab/Synoptic-Bench huggingface dataset:
The NAM MOS has trended slightly warmer whereas the GFS MOS has held steady. Both show below freezing or near freezing temperatures overnight away from the coast. The greatest threat window for freezing temperatures will be in the 3AM-8AM timeframe. In the upper levels a ridge will move into the region from the Great Plains. At the surface cool, dry air will remain in place as high pressure dominates the Southeast. Highs will be in the mid to upper 60s on Monday afternoon and in the lower 70s on Tuesday afternoon. Lows will be in the low to mid 30s on Monday night and in the low to mid 40s on Tuesday night.
Quiet weather for the next couple of days as deep layer moist cyclonic flow is gradually replaced by prominent upper ridging forced by continued western US height falls. This will in turn support a slight improvement in temps, especially southeast of the ridge, and perhaps a few hours of sunshine at least over the SE half of the CWA. Recovery in the wake of the thermal trough will support highs in the upper 30s.
Upper ridge will dominate the weather today and tonight with light winds, scattered cirrus and mild temperatures in the upper 50s to middle 60s this afternoon. The next feature to affect the forecast area is the upper trough currently moving onshore along the West Coast as seen in weather vapor imagery. Latest numerical guidance shows the trough making steady progress eastward toward the Four Corners area tonight and Monday, lifting out over the High Plains Monday night and Tuesday.
High pressure at the surface and slightly rising H5 heights will keep the region dry through at least Tuesday morning. A warm front associated with a developing system over the central plains will lift northeast across our CWA Tuesday morning but due to a lack of moisture it should remain dry. As the system/associated cold front draws nearer, precipitation chances increase and spread eastward across our CWA Tuesday evening through the overnight hours.
Raised wind speeds some behind this cold front given the fairly tight pressure gradient in its wake.
1122 PM CST Sun Nov 20 2016 Rather progressive pattern progged over the next several days with a series of longwave trofs. upper ridge over the cntrl U. begins to break down in response to lead longwave trof pushing ashore over the west coast. Models in pretty good agreement developing pcpn just west of the CWA Monday evening along a warm front.
Current surface observations showing temps in line with latest guidance and continue to expect min temps briefly near freezing in northern Levy county with lower to mid 30s the rest of the Nature Coast.
1140 PM CST Sun Nov 20 2016 A large upper level ridge sits over the central portion of the country with an elongated area of high pressure extending along the Mississippi River creating dry conditions with average temperatures around the region. With clear skies temperatures will drop back down below freezing for most areas with the KC metro area staying slightly above freezing tonight. Initial precipitation will form up early Tuesday morning along the nose of the LLJ and isentropic lift with strong WAA in the low levels.
340 AM CST Mon Nov 21 2016 High pressure ridge over the dvn cwa providing clear skies, calm to light winds and cold temperatures. Today: The morning will start out clear and cold but gradually winds become southeast allowing for somewhat of a warmer day. The ridge will shift east of the cwa this afternoon with weak warm air advection kicking in. Towards morning stronger forcing begins to spread into the cwa but the low levels of the atmosphere will still be quite dry. The clouds along with a gradual increase in southeast winds will make for a warmer night, compared to the past few nights.
320 AM CST Mon Nov 21 2016 Its already a much warmer morning than the previous two. This appearance of the perennial and hot upper ridge will not last long though when a front moves through Oklahoma during the day Tuesday.
252 AM CST Mon Nov 21 2016 A few breezy southeasterly winds will be possible this afternoon as the pressure gradient remains between he exiting ridge over WI and the nearing trough nudging into western SD. The 500mb trough extending along the west coast early this morning will remain an open wave as it pushes into and across the Plains States early Tuesday morning.
Our surface winds are showing the back edge of the ridge axis with still NE at MLU and S/SW over much of our Western half or so. However, we will will keep some freezing temps in play again overnight East and with dewpoints returning still in the 20s much of the area will be below average once again. Either way, all of our sites have reached or dipped below the freezing mark verifying last night's freeze warning area wide.
/ISSUED 938 PM CST Sun Nov 20 2016/ Surface ridging continues to maintain its influence on the region, but evening surface analysis shows that this feature has begun to shift east of the region. As a result, expect overnight temperatures a few degrees warmer than what was observed this morning with lows in the mid 30s to mid 40s inland and low 50s along the coast. /ISSUED 353 PM CST Sun Nov 20 2016/ A bit cooler last night than expected for northern areas of the FA. Light onshore winds are expected to develop tonight and then strengthen by tomorrow afternoon as the next upper trof begins to move in from the west. This first upper trof will help to drag a cold front across the region starting late in the day on Tuesday.
High pressure Monday afternoon through Tuesday. A weak cold front mid week. Winds in the higher elevations have not have gusts over 40 mph since mid evening. Upslope stratus deck will gradually dissipate this morning as warm air advection occurs in the lower levels. Clouds will be on the increase across the area on Tuesday, as a warm frontal boundary lifts north across the region.
408 AM EST Mon Nov 21 2016 Skies are clear with temperatures ranging from the lower to mid 60s in the Upper Keys to the mid and upper 60s elsewhere. Surface wise, high pressure is centered over the western gulf states with a lengthy ridge reaching through the Gulf of Mexico and across the southern portion of the Florida peninsula. An expansive deep tropospheric anticyclone centered over the western Gulf of Mexico will build eastward and strengthen across the Sunshine State over the next several days.
SHORT TERM (Today through Tuesday): During the forecast period, a mid- level ridge of high pressure over the Lone Star State will shift east as a 500 mb trough of low pressure pushes into the western half of Texas. At the surface, high pressure across the Gulf of Mexico will interact with low pressure moving east through the Central Plains, resulting in warming and above normal temperatures.
415 AM EST Mon Nov 21 2016 Cool high pressure will prevail into the middle of the week.
Weak low-level warm advection will begin to slowly draw a bit more moisture northward overnight, but the main push will wait until Monday and Monday night ahead of an approaching low pressure system. /ISSUED 255 PM CST Sun Nov 20 2016/ Low level warm air advection will increase across the region through Monday night ahead of a developing low pressure system currently off the West Coast. The increase in low level moisture will result in a much warmer night tonight with overnight lows generally in the 40s. Shower/thunderstorm chances will return to the entire region Tuesday as the upper level trough moves into the Central and Southern Plains and a cold front sweeps across the region. Although some warm air advection showers will be possible ahead of the cold front the best storm chances will be along the front Tuesday afternoon/evening.
High pressure Monday and Tuesday. A weak cold front mid week. Cold, strong west to northwest flow continues this period, as a large, stacked low pressure system slowly pivots into the St. The advisory for snow and wind across the high terrain continues through tonight unchanged with small additional snow accumulations. Clouds will be on the increase across the area on Tuesday, as a warm frontal boundary lifts north across the region.
1123 PM CST Sun Nov 20 2016 At h5 deep trough along the west coast with strong ridge over the Rockies and strong closed low over the northeast CONUS. Dry conditions continue as an upper level ridge continues to build over the central US. Recent snowpack combined with warmer temperatures aloft could allow some patchy fog to develop in this location. Overnight lows remain below guidance as recent snowfall will continue to keep temperatures cooler than anticipated. Lows drop into the low to mid 20s. Despite the increasing clouds, temperatures will still rise into the low 50s. Nam is colder and the availability of cooler air with this system will determine precipitation type.
248 AM CST Mon Nov 21 2016 Early morning water vapor imagery detects a well-defined upper low spinning just off the southern CA coast. The best chances of storms may hold off until late Tuesday afternoon/early evening (primarily across southeast OK/western AR) as the cold front eventually overtakes the dryline and the main upper trof punches into the area. Drier and cooler weather expected behind the front for the remainder of the week. with another weak (and dry) cold front moving through Thanksgiving night.
1226 AM EST Mon Nov 21 2016 Cool and dry high pressure continues to build into the Ohio Valley today, with temps really struggling in the face of the low-level thermal trof. North-south oriented ridge will settle roughly overhead tonight, and winds should drop off for favorable radiational cooling conditions. Expect min temps a few degrees cooler than this morning, with more of a ridge/valley spread. Below normal temps will continue on Monday, but should still be about 5 degrees warmer than this afternoon. Progressive pattern will prevail for most of the week, keeping temps just barely on the low side of climo.
235 AM EST Mon Nov 21 2016 Low pressure over Quebec province will remain nearly stationary through early Tuesday. This low will maintain a blustery westerly flow across the area along with a few upslope snow showers mainly across the higher terrain.
258 AM CST Mon Nov 21 2016 Cold high pressure was sitting over the Mid State this morning. Daybreak temps will be in the low to mid 20s, with some teens in the usual colder spots. Through the day, sunshine will boost temps into the lower 50s with light winds. Tuesday will bring better temperature recovery as the high pressure center moves off to the east.
430 AM EST Mon Nov 21 2016 High pressure will build across the region today and Tuesday.
The central part of the state appears to be the favored location for the lower visibilities and have gone with areas of fog in that region. Thermal profiles still suggest warm enough air aloft to support a period of light freezing rain before changing to snow. Low pressure across central Montana will move eastward slowly, reaching western ND Monday evening.
Cross sections and forecast soundings already indicate moist levels above 500mb and this trend will continue as moisture infiltrates the lower levels. Currently, the upper level trough and surface cold front are moving ashore along the West coast. The models have indicated some banding setting up as the trough moves overhead late Monday evening through Tuesday morning for those areas. Lingering snow showers will continue for the higher terrain Tuesday as northwest flow sets up behind the trough and cold front. Expect high temperatures to drop several degrees Tuesday thanks to cooler air advecting in.
Cold high pressure extending from Hudson Bay Canada to the Gulf of Mexico will move southeast and provide clear skies. Another cold night tonight across the inland areas with light winds/decoupling and have gone with previous forecast of slightly cooler than guidance with low in the lower/mid 30s inland which will fall just short of a freeze warning but will most likely have patchy frost most areas away from the river/coast with a few pockets of near freezing across the normally colder locales.
For Monday, upper level ridging moves over the area as breezy southeast winds develop.
A 1030 mb high pressure ridge sprawled across the MS river valley, will drift slowly eastward across IL and into IN by sunset Monday. Meanwhile an upper level ridge over the High Plains will drift east toward the MS river valley by early Monday evening. The low stratocumulus clouds (bases 3-4k ft) will stay ne of Hoopeston/Vermilion county rest of today, associated with strong 523 dm 500 mb low exiting over New England.
Surface analysis this afternoon places a 1029 mb ridge of cold high pressure over the Lower Mississippi Valley. A ridge of high pressure will continue to bring rain free weather to the Mid-South tonight through Tuesday.
1230 AM EST Mon Nov 21 2016 High pressure builds into the region into Monday.
1241 AM EST Mon Nov 21 2016 High pressure will build over the region through Tuesday.
The southeastern ridges will be a little tricky. However, the coldest air over the ridges will begin to retreat northward later this morning, so this should really decrease snow coverage by late morning. Upper level heights finally begin to rise tonight and through Tuesday as a broad ridge builds into the Tennessee Valley. Once the warmer air heads eastward, the persistent cloud cover will quickly erode.
338 AM CST Mon Nov 21 2016 Relatively quiet weather will continue across North and Central Texas today as an upper ridge remains in control of the region. Activity will then surge east during the late evening and overnight hours, with cooler and drier air spreading in on the back side of the trough and behind the cold front. A stronger trough will move quickly southeast from the Great Basin into the Southern Plains as we move through the weekend.
303 AM EST Mon Nov 21 2016 Aloft - Ridging centered over the Gulf of Mexico extended to the Canadian Prairies while a low was above New England. Surface - High pressure over western Ontario sprawled south. The upper ridge shifts eastward with an axis from FL to Hudson Bay while the upper low slips over the Canadain Maritimes. The only location that may reach freezing is Levy but briefly. A generally dry stable and cool air mass prevails but slowly moderates as the ridging. As a result the low level flow shifts from northerly today to north- easterly by Tue.
1148 PM CST Sun Nov 20 2016 High pressure will move east of Arkansas today. with temps a few deg warmer for Mon morning lows. with a cold front moving east across OK towards AR. Better chances for precip across a larger portion of the state will come Tue night into early Wed as the cold front progresses east across AR.
Expect the lowest temps of the season so far tonight over interior areas around Glades and Hendry counties with morning lows near 40. Generally dry and benign weather will continue on Monday and during the next couple of days across South Florida with broad high pressure well in control of the region. Expect the colder temperatures of the season with portions of South Florida experiencing morning lows in the lower 40s, especially Glades and Hendry counties, and areas around Lake Okeechobee. Winds will continue to subside through Monday as broad high pressure spreads across the region. Morning temps on Tuesday will be a little warmer.
/issued 322 PM CST Sun Nov 20 2016/ The upper level ridge responsible for our gorgeous blue skies and warmer temperatures today will begin to break down on Monday, allowing the approach of an upper level trough. Models are in fairly good agreement on the placement and strength of this trough by the end of the forecast period, with the center over central AZ. Lift associated with the upper trough will pass over the area Monday evening. Dry front to sweep across the area Tuesday as the trough swings across the central plains.
345 AM CST Mon Nov 21 2016 (Today and Tonight) Currently, an upper level ridge is over Texas, and an upper level trough is entering the California coast. The upper level ridge will weaken and shift east into the lower Mississippi Valley today, while the upper trough moves east across the Great Basin and Desert Southwest. Temperatures will be warmer today with highs expected to be in the mid 70s across much of our area. The aforementioned upper trough will move east across the central and southern Rockies tonight, with the lead portion of the trough lifting northeast into the central High Plains by early Tuesday morning. But given the forecast track of the upper trough and associated lift, along with limited moisture return into our area, decided to hold off with any mentionable PoPs for now.
On Monday, a cold front will move into Arizona lowering snow levels and bring some light snow accumulations to the high country during the afternoon and evening hours. Dry and warmer weather will return on Tuesday, lasting through the week. There will be a break in shower activity as the plume moves east and the cold front approaches. A cold front will move from west to east across northern AZ on Monday.
Dry northwest flow aloft will meanwhile persist across our forecast area on the northeastern and northern periphery of an upper level ridge of high pressure building across the Gulf of Mexico. Ridging aloft will extend northward over our area Monday as the parent upper high continues to build across the south central and southeastern Gulf of Mexico.
250 AM EST Mon Nov 21 2016 High pressure will build southeast from the upper Midwest to over the mid-Atlantic region through late Tuesday.
Will go with slightly better chances for areas east of the KS Turnpike, where some model solutions suggest the low level moisture will have the best chance to return. Not expecting much of a cool down on the backside of the Tue system, with cooler air with the cold front actually pushing temps back towards climo normals for Wed. Lee troughing continues to slowly strengthen over the high Plains and this is expected to continue as the upper wave approaches.
It will push eastward overnight with southeast Oregon and the lower Snake Plain drying out by 06Z, while southwest flow aloft will keep shower activity in the southwest Idaho mountains through the night. The showers extend west to the coast and were associated with an upper trough. The axis of the trough was located near the west coast. The showers will shift eastward tonight through Monday morning as the upper trough and weak cold front move through the region. Total snowfall amounts of up to 2 inches are expected in the higher mountains. An upper ridge will traverse the region Monday night. Mostly clear skies and light winds could lead to patchy late night and morning fog in the Lower Treasure Valley (e. The upper ridge will shift east, replaced with a dry southwest flow aloft on Tuesday.
An upper level trough and Pacific storm system will move into the central plains to start off the workweek. On Tuesday the Pacific system will push the low into western and central Kansas leading to some spotty rain showers. Lows tonight are expected to be in the lower 30s. A trof will move out across the Plains Tuesday morning. The low will cause the pressure gradient to increase and thus Tuesday will be on the breezy to windy side. Cooler highs are expected in the wake of the system.
145 pm PST radar shows a line of precipitation extending along a cold front from Yosemite National Park south through San Luis Obispo.
320 AM CST Mon Nov 21 2016 Compact upper low offshore of Los Angeles early this morning is on track to become an open wave later today while lifting across the Four Corners. With deeper moisture deficits looming over the eastern High Plains, the feeling is that nothing more than an opaque middle cloud deck with some sprinkles will enter our western zones this afternoon, before expanding east tonight ahead of the trough axis and aggressive drying/clearing toward daybreak. Max temps were adjusted a bit cooler in our NW where clouds will be most prevalent, while raising values farther east in tune with the milder MAV and ShortBlend guidance. Dry front on Tuesday pushes south-southeast across our area below a secondary vort max at the base of the exiting trough to our east.
Looks like current temp trend is on track to get down into the low to mid 20's for overnight lows.
347 AM CST Mon Nov 21 2016 Early this morning satellite imagery shows the region under the influence of a progressive upper level ridge with a notable trough seen swinging onshore across the West Coast.
310 AM CST Mon Nov 21 2016 An upper level ridge is spreading east across the Plains early this morning and will spread over the region today. Southerly winds will usher warmer conditions into the area from west to east. An upper level trough and front will approach from the west and spread across the region Tuesday and Tuesday night. Showers may linger into the overnight hours with the passage of the trough. Slightly cooler conditions will spread into the area behind this system for the rest of the week with highs in the 50s and lows in the 30s expected each day.
109 AM EST Mon Nov 21 2016 Cool high pressure will prevail into the middle of the week.
temps look on track to reach previous forecast mins, maybe a couple degrees warmer in a few spots. The large high pressure ridge over the central U. High pressure to the north drifts eastward, crossing the Carolina/mid Atlantic coast during the mid week.
As this continues overnight, ample radiational cooling will allow temperatures to fall well below freezing in most locations. An upper ridge extending from the western Gulf of Mexico northward through the central Plains will shift east into the lower MS Valley by late Monday.
1130 PM EST Sun Nov 20 2016 Cool high pressure will build into the Carolinas today, then settle overhead Monday and Tuesday.
335 AM EST Mon Nov 21 2016 High pressure will build southeast from the upper Midwest to over the mid-Atlantic region through late Tuesday.
The southeastern ridges will be a little tricky. However, the coldest air over the ridges will begin to retreat northward later this morning, so this should bring and end to any lingering snow by late morning. Upper level heights finally begin to rise tonight and through Tuesday as a broad ridge builds into the Tennessee Valley. Once the warmer air heads eastward, the persistent cloud cover will quickly erode.
VFR conditions expected through the next 24 hours with high pressure in the vicinity. Light and variable winds and CAVU overnight as high pressure remains in the vicinity.
As high pressure filtered into the region, the pressure gradient relaxed which resulted in calmer winds today. Given the dry ground, we are expected to get cooler tonight for most locations than last night/this morning and another widespread freeze is expected. Upper level ridging will also take hold and this will allow for a dry, sunny and slightly warmer day. North/northeastern locales may only top out in the lower to mid 60s after a much colder anticipated start. Still went with a limited risk for fire danger in the east given the low RH values. The regular trough passages will keep temperatures closer to seasonal normals as there will be no prolonged periods of warming or cooling during the week.
Synoptic Setup: short term begins with a series of Ridges and trouGH setting upstream from eastern Montana. First ridge lies over eastern Montana and Runs down the High Plains into Texas. First Trough lies over the Pacific Coastline stretched from California to British Columbia. The Next ridge/trough couplet lies over the Gulf of Alaska. Today through Tuesday: Ridge will exit the area and the trough will enter by Tuesday Morning.
1252 AM EST Mon Nov 21 2016 Upper level low pressure over New England is gradually moving away from the Ohio Valley.
Height rises aloft are expected as an upper ridge builds ahead of a strong upper trough that will track from the sw USA into the central Great Plains.
944 PM MST Sun Nov 20 2016 Broad upper-level ridging remains intact over much of the western/ central CONUS this afternoon. A weak upper ridge translates east across the region Tuesday night with small PoPs for snow in the evening across the Sierra Madre and Snowy Ranges.