Aikyam-Lab/Synoptic-Bench huggingface dataset:
A little cooler today, but all-in-all, not a half bad day. This is an expected development as models tend to shift northward or southward with time, but what it means is the exact locations that will get the highest amounts is still yet to be determined.
641 PM EST Thu Feb 25 2021 High pressure will provide dry conditions tonight and Friday before a series of low pressure systems bring periods of rain through the weekend. Dry conditions and light winds will prevail under the high with low temperatures in the mid to upper 20s. A mid-level trough over the four corners region will begin to head east on Friday. Meanwhile, surface winds shift to the northeast and east with the departing high pressure.
943 PM EST Thu Feb 25 2021 High pressure will provide dry conditions tonight and Friday before a series of low pressure systems bring periods of rain through the weekend. Lows tonight range from the low/mid 20s in west-central/central Ohio to around freezing south of the Ohio River. Dry conditions and light winds will prevail under the high with low temperatures in the mid to upper 20s. A mid-level trough over the four corners region will begin to head east on Friday. Meanwhile, surface winds shift to the northeast and east with the departing high pressure.
For tonight, s/w ridging should serve to keep the region dry, although some cloudiness is expected to migrate over the region. For Friday a slightly warmer airmass is expected to advect into the region, with even warmer temperatures expected. Have struck a bargain between using the 75/90th NBM percentiles for the high, particularly given today's temperatures. Lows on Friday night should be a touch cooler given slackening winds across the forecast area.
A dry cold front has pushed through the area today bringing windy conditions out west and breezy conditions around Phoenix and the lower deserts as well as cooler temperatures.
443 PM MST Thu Feb 25 2021 The 12Z H500 hand analysis map is showing a fairly wavy pattern from the deep trough over the 4 Corners upstream to the highly amplified ridge over the E. The sounding this morning at GJT had us in the lower realm of normal but subsidence and drying behind the trough should put us deeper in deficit by the next balloon launch. There will be a thin line of moisture aloft moving through at the interface of the retreating ridge arriving trough by morning.
Dry weather will continue through much of tomorrow as high pressure tracks across the region. The higher level cloud shield will gradually shift east late tonight with skies becoming mainly clear after 06Z. Even as high pressure drifts east through the night. As the influence of subsidence weakens over the area and an upper trough approaches, models show a plume of moisture advancing northward into the southern stretches of the CWA. A low pressure system will lift northeast across the upper Midwest, Great Lakes and into Quebec this weekend.
733 PM EST Thu Feb 25 2021 High pressure will track overhead tonight into Friday morning.
749 PM EST Thu Feb 25 2021 High pressure will track overhead tonight into Friday morning.
Result of the clouds/winds may be less radiational cooling and there is potential that some locations hold steady around or above freezing. Colder spots would be in the 20s, still warmer than previous nights.
By tomorrow, another cold front is expected to approach southern Oregon. Travel impacts around the 3000 to 5000 foot level are more uncertain because of warmer sub surface temperatures keeping roadways relatively warm. These probabilities seem to hedge on the lower side based on what is usually observed in winter storms. With snowfall rates approaching 1 inch per hour Friday, there could be travel problems over the high Cascades during Friday. Because of the probabilities and snowfall rates, we decided to issue a winter weather advisory over the high central Cascades Friday.
319 PM CST Thu Feb 25 2021 High pressure will move through Illinois this evening.
/Issued 154 PM CST Thu Feb 25 2021/ Upper level open short wave trough just passing by the 4-corners region is expected to move across the Panhandles tonight with little fan fair.
Advection fog looks very favorable tonight as light onshore flow of 5 to 10 mph allows warmer air to pass over the cooler nearshore waters.
Temps have been very slow to fall off tonight and have had to make some adjustments, especially south of the warm front.
202 PM MST Thu Feb 25 2021 Weak ridging continues to sweep across the state, keeping things mostly tranquil this afternoon. Low pressure across Canada is tightening the gradient across the northern US, currently impacting the main central WY wind corridor and South Pass. The next weather system will sweep across the pacific northwest during the next 24 hours, bringing the first of two troughs across the western parts of the state Friday.
Clouds are expected to clear out through the overnight hours as lows dip below freezing.
553 PM CST Thu Feb 25 2021 High pressure will move through Illinois this evening.
304 PM CST Thu Feb 25 2021 Another dry day today, a little cooler than the last couple of days but still seasonable.
(Today and Saturday) Trough and associated precip is expected to be well east of the area by sunrise, however cloud cover will be slow to erode.
1000 PM MST Thu Feb 25 2021 Weak ridging continues to sweep across the state, keeping things mostly tranquil this afternoon. Low pressure across Canada is tightening the gradient across the northern US, currently impacting the main central WY wind corridor and South Pass. The next weather system will sweep across the pacific northwest during the next 24 hours, bringing the first of two troughs across the western parts of the state Friday. By Saturday morning snow showers will be ongoing across the area, mainly in the west and northern mountains, as the main trough axis continues to pull through the area with a front at the surface.
1037 PM EST Thu Feb 25 2021 High pressure will track overhead tonight into Friday morning. A weak area of low pressure will lift up the east coast Friday night into Saturday.
Will need to keep an eye on this overnight and see if lows will be slightly warmer than what is in the forecast at this time. A upper level trough will dig south across the central Plains resulting in a weak area of disturbance on the leeward side of the Rocky Mountains. With temperatures in the low 40s, any precipitation that does develop will likely start as rain before changing over to snow. Dry weather returns for the latter half of the weekend, however, temperatures will remain near normal (low to mid 40s) as the upper trough continues to dig further south and cooler air from Canada gets pulled into the region.
Near the surface, boundary layer convergence will enhance lift along the warm front. Tonight, low clouds and patchy showers or drizzle will continue across the area with highest rain chances across our northwest zones near the low-level frontal boundary. As the warm front lifts north, moisture will be on the increase for the weekend.
928 PM CST Thu Feb 25 2021 High pressure will move through Illinois this evening.
/Issued 154 PM CST Thu Feb 25 2021/ Upper level open short wave trough just passing by the 4-corners region is expected to move across the Panhandles tonight with little fan fair. Southerly winds will pick up ahead of it across the eastern Panhandles and the central Panhandles will likely have winds decrease in the afternoon with the trough in the area. The western Panhandles could see winds pick back up again to the west of the trough and just ahead of a cold front. A cold front moves through the Panhandles Saturday night ahead of an upper level trough moving south through Utah.
1037 PM MST Thu Feb 25 2021 The 12Z H500 hand analysis map is showing a fairly wavy pattern from the deep trough over the 4 Corners upstream to the highly amplified ridge over the E. The sounding this morning at GJT had us in the lower realm of normal but subsidence and drying behind the trough should put us deeper in deficit by the next balloon launch. There will be a thin line of moisture aloft moving through at the interface of the retreating ridge arriving trough by morning. Cold advection and orographics will help force snow development in the higher elevations from late morning Friday through Saturday evening. Right now the highest amounts continue to be focused on the highest terrain in the Park Range. Unfortunately as this trough digs into the 4 Corners late Saturday.
1213 AM EST Fri Feb 26 2021 High pressure will keep the region dry through Saturday morning. Building high pressure will maintain dry weather today. The synoptic setup over the weekend will feature midlevel ridging nudging into the SE CONUS allowing a return flow into the forecast area. This will set the stage for a wintry mix in the higher elevations Friday night before changing to all rain for Saturday and Saturday night.
1236 AM EST Fri Feb 26 2021 High pressure will provide dry conditions tonight and Friday before a series of low pressure systems bring periods of rain through the weekend. Lows tonight range from the low/mid 20s in west-central/central Ohio to around freezing south of the Ohio River. Dry conditions and light winds will prevail under the high with low temperatures in the mid to upper 20s. A mid-level trough over the four corners region will begin to head east on Friday. Meanwhile, surface winds shift to the northeast and east with the departing high pressure.
Friday night will be similar, with lows in the lower to middle 60's, warming into the upper 70's to near 80 Saturday.
Cloud cover will help hold temperatures in the upper 40s to lower 50s despite the warmer return flow, but will shift off to the east and not linger long enough to impact overnight temperatures tonight. Sunnier and warmer conditions are expected Saturday; and with breezy southerly winds, fire danger will be slightly elevated mainly west of the area where RH may be lower.
Increased clouds have kept temperatures cooler than yesterday with highs topping out in the mid 40s. The plume of moisture is quickly swept east by the mid level trough, although there could be a brief window where light rain/sprinkles is supported in the eastern half of the CWA. Temperatures in north-central Kansas will warm into the low to mid 50s while cloud cover over east-central Kansas will keep temps near the 50 degree mark. Southerly winds strengthen on Saturday as a lee cyclone deepens over southeast Colorado and southwest Kansas. Increased WAA will boost temperatures into the low to mid 60s Saturday afternoon. It will be worth watching the timing of this trough as winds behind it are more supportive of downslope flow, which would further lower RH values.
An upper trough was moving into the NW quadrant of the US today. This cold front drops south through the CWA late Friday with some isolated disturbances moving through in the NW upper flow late in the day. The lower levels look too dry to allow for much precip to reach the ground but felt it was enough to broadbrush low chance pops with little/no qpf Friday afternoon and Friday evening. Mainly clear skies are expected Saturday night before an upper ridge moves in for early in the week.
1147 PM CST Thu Feb 25 2021 High pressure will move through Illinois this evening.
On Friday, clouds will begin to gradually increase by afternoon with the approach of an upper-level trough and increasing mid-level moisture. As the aforementioned trough continues eastward across the Midwest Friday evening into the first half of the night, light rain will be possible for portions of the area. Pfahler Any remaining light rain showers should exit the forecast area by Saturday morning as the upper-level trough continues northeastward across the Great Lakes. In the trough's wake, a very nice spring- like day can be expected for much of the region.
An approaching upper broad trough and front will quickly shut the winds off Friday evening. Some light snow shower activity is expected with the cold front passing through Friday night, before more widespread, yet still light snow will occur behind it throughout Saturday.
The one factor to watch, however, will be the high clouds streaming in ahead of a surface pressure trough currently draped over eastern Montana. Winds will become breezy again Friday afternoon as a cold front approaches from the west. The aforementioned cold front approaches Friday night, bringing with it slight chances of rain or snow to the west with a better chance of snow (but still light and brief) across the north central. Highs during the afternoon will range from the single digits across the Turtle Mountains, to the lower 30s across portions of the south (so basically close to normal for this time of year, maybe just a bit below).
1019 PM CST Thu Feb 25 2021 (This evening through Friday) There is a chance of showers with an isolated thunderstorms tonight, as an upper trough moves across the West central Texas, lifting warm air over the cold air at the surface.
Currently a weak frontal boundary is holding down near the gulf coast, with a few LL weak trough axes extending up into the mid-south.
1231 AM EST Fri Feb 26 2021 High pressure will track overhead tonight into Friday morning. A weak area of low pressure will lift up the east coast Friday night into Saturday.
Clouds are expected to clear out through the overnight hours as lows dip below freezing. Brisk southerly flow and substantial warm air advection elevates temperatures Saturday into the low 60s.
223 AM EST Fri Feb 26 2021 High pressure will track overhead tonight into Friday morning. A weak area of low pressure will lift up the east coast Friday night into Saturday.
Deep ridging was aligned along 27 North Latitude in the western Atlantic in the lower troposphere, tilting southwestward with height. Weak high pressure ridging across the central Florida Peninsula was maintaining light to gentle east winds, except northeast over the Gulf waters beyond 5 fathoms.
There is a pretty decent dry area in the lower to mid levels of the atmosphere (see 00z SGF sounding) and pretty large dew point depression. Enough lift and moisture will cause some showers to make it into southern MO today, but mainly over the lower two tiers of counties. CAMS models are showing signs of fog developing (some dense) late tonight into Saturday morning and have added the lower visibiities and fog into the forecast. We are generally going with lows above freezing in the mid to upper 30s tonight, so we are not expecting any widespread freezing fog.
There is good model agreement in saturating the low levels southeast of the KS Turnpike today with some isentropic upglide within this saturated layer. Also did go ahead and insert some fog for southeast KS late tonight into Sat morning as moisture continues to increase in the low levels. This will result in a Pacific cold front/dry line extending through west-central KS.
Saturday will be a little cooler as the marine layer deepens and the onshore flow increases ahead of an approaching trough.
The active mid/upper pattern will continue into the weekend as a highly amplified longwave positively-tilted trough stretches across a good portion of the Lower 48.
This, along with cloud cover, is helping to keep temperatures region wide in the low to mid 30s. Usually with a cold frontal passage, north winds get fairly gusty.
1028 PM EST Thu Feb 25 2021 Currently - A weak high pressure system sits across Florida, resulting in light mostly northeast to east breezes across the Keys and surrounding waters. Short Term Update - Weak ridging will remain across Florida through the overnight period keeping winds light out of the northeast to east. Lower to mid level ridging will persist along with very dry air aloft. Temperatures will bottom out in the lower 70s. A bit warmer than last night due to the more veered flow. Weak high pressure across Florida will result in light winds becoming more east northeast to east by morning.
Another dry day today, a little cooler than the last couple of days but still seasonable. Saturday: Looks dry and warmer with more sunshine expected with highs in the 60s common.
On Friday this energy will form a strong upper trough over interior WA and OR and then swing right into our CWA, bringing heavy snow to our northern and central mountains and strong winds to cause blowing and drifting.
The higher coverage will be focused near the front, so generally along and north of a line from Tuscaloosa to Anniston with more scattered to isolated coverage expected to generally north of I-85. Elevated instability will produce some thunder along with the higher rain rates, but very poor sfc-3km lapse rates and weak upper-level support will limit any stronger storms. The highest PoPs will be located the the north of our forecast area in closer proximity to the front.
Nevertheless, it appears we'll see at least 40 mph gusts from late morning through mid afternoon until the winds aloft weaken with an approaching low pressure area from the Dakotas. Saturday night a low pressure system tracks south of the CWA through Iowa and southern Wisconsin.
On Friday, brisk wly flow at aloft across the area, while surface lee trough develops along I-25. Much of the area will become breezy and warmer by afternoon, though fairly deep snow cover over El Paso county will hold back temps somewhat. Upper trough drops through the area Friday night into Saturday, bringing another light round of snow to the central mountains.
317 AM MST Fri Feb 26 2021 Forecast challenges will focus on the cold front and its associated precipitation beginning this evening.
A generally zonal flow across the lower-48 was beginning to amplify (with troughing developing over the western states), as a powerful system headed SE along the British Columbia coast. With clouds and good rain chances high temperatures today should remain a bit cooler, rising to around 60 degrees. The boundary should creep northward tonight, partially in response to the amplifying trough out west.
726 AM EST Fri Feb 26 2021 High pressure will keep the region dry through Saturday morning. This will support beautiful weather today, before increasing clouds this afternoon and no real warm reinforcement cap the high temperature likely just below 50 degrees. Previous Discussion: Building high pressure will maintain dry weather today. With weak ascent expected everywhere, with the exception of portions of the ridges, precip may not reach the ground until midnight due to lingering dry air. In eastern Tucker, freezing rain is expected to occur this evening and overnight due to cold air damming as a result of sely flow, and warmer swly flow aloft. A period of ridging in eastern Ohio may create a break in precip Saturday night. especially near the ridges.
401 AM EST Fri Feb 26 2021 High pressure will keep the region dry through Saturday morning. Building high pressure will maintain dry weather today. With weak ascent expected everywhere, with the exception of portions of the ridges, precip may not reach the ground till midnight due to lingering dry air. In eastern Tucker, a brief period of isolated freezing rain may occur overnight due adiabatic cooling with upslope flow (reference HWO). A period of ridging in eastern Ohio may create a break in precip Saturday night. especially near the ridges.
419 AM MST Fri Feb 26 2021 WV imagery tonight indicates broad trof being carved out across the nrn Rockies. A few embedded impulses can be identified within the broader trof, most notably one just to our west across the nrn High Plains and another near the Pac NW. Otherwise, earlier downslope winds have largely abated across the nrn foothills as sfc trof axis and attendant front have shifted ewd. If current timing and placement stands, temperatures could be in the low to mid 30s for approximately half of the precipitation, which may significantly cut into any snowfall totals.
410 AM CST Fri Feb 26 2021 Summary: Today will have above average temperatures in the high 30s.
Models are still hinting at some showers or virga with a backdoor cold front Friday night. With H85 temps falling to around -4C early Saturday morning, went a little cooler on temps than deterministic guidance Friday night. Model QPF is a bit higher compared to previous runs, with deterministic GFS and NAM both showing spots getting into a quarter inch or higher, and that reflects in the GEFS plumes which have increased the range of amounts, although the average is still right around a tenth for KATY though I would expect the lower resolution of the GEFS may have difficulty if this ends up being a mesoscale feature (it is important to note that the band develops in a dead space area where there aren't plumes available, so that may be the reason we're not seeing any extremes as well).
432 AM MST Fri Feb 26 2021 A shallow Pacific mid-level trough continued to approach the region during the night, driving a short-lived transient ridge to the east. A very modest moisture feed ahead of the trough will just brush the northern zones bringing occasional light snow showers to the Elkhead and northern Park Range today with areas of altocumulus to the northern and central Colorado valleys.
There is a cold front that moves through during the day.
Went ahead and issued a Winter Weather Advisory for the higher peaks, with snow totals of around 8 to 10 inches possible. A secondary cold front is expected to dig southward on Saturday, bringing widespread snow across the northern and western half of the CWA. Snow totals appear light at this time with only around a half inch expected around Converse County, under an inch for areas west of Chadron, and slightly higher totals to the west along the higher peaks.
948 AM EST Fri Feb 26 2021 After a cool start in the lower to mid 50s this morning, temperatures have rebounded very quickly with the dry airmass and full sunshine. Atlc ridge axis will build westward across the area and in response wind flow will veer SE and increase 10-14 knots.
621 AM EST Fri Feb 26 2021 High pressure will keep the region dry through Saturday morning. Building high pressure will maintain dry weather today. With weak ascent expected everywhere, with the exception of portions of the ridges, precip may not reach the ground till midnight due to lingering dry air. In eastern Tucker, a brief period of isolated freezing rain may occur overnight due adiabatic cooling with upslope flow (reference HWO). A period of ridging in eastern Ohio may create a break in precip Saturday night. especially near the ridges.
Water vapor is also showing a second trough over the northern Rockies that the models have moving east and weakening across the Midwest tonight. Going forecast has a good handle on this so will keep chance PoPs this afternoon into this evening as the area will lie under the weak ascent associated with the trough. Temperatures are expected to be above normal the next two days, with highs around 50 today given 850mb temps in the 0-5C range and easterly surface winds and highs around 60 on Saturday with slightly warmer low level temperatures and southerly winds.
Snow shower activity will gradually retreat to the higher terrain Friday night into Saturday morning.
/issued 427 AM CST Fri Feb 26 2021/ This morinng freezing temperatures across the upper plain states will some snow reported along the eastern slopes of the rockies in Montana. Down into the southern states a stationary frontal boundary is the focus of showers and thunderstorms moving above the warm front from northeast Texas in Arkansas.
A cold front is currently located over the very northwestern tips of the forecast area as of writing of this discussion. Most of the high res models suggest the front stalls generally along a line from Victoria to Alice. The front will move back to the west as early as tonight as a warm front.
Widespread showers a few embedded thunderstorms occurred north of a surface warm front over central MS early this morning.
Temperatures will continue to routinely hit the lower to middle 80s across much of the CWA with warmer temperatures out west, along with lows ranging from the lower to middle 60s across the area.
In addition, periods of gusty north winds may occur across exposed ridges and coastal areas.