Aikyam-Lab/Synoptic-Bench huggingface dataset:
Low level warm/moist advection will continue through the day in advance of an approaching low pressure system. The low ceilings should remain in place until a cold front moves through Tuesday evening. Some warm air advection showers will be possible ahead of the cold front Tuesday afternoon. /ISSUED 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.
340 PM CST Mon Nov 21 2016 Afternoon water vapor imagery features upper low now over AZ with scattered showers and thunderstorms across eastern AZ/western NM. Upper low will track across KS and eastern NE by Tue evening. with a surface cold front arriving in eastern OK/western AR late Tue into early Wed. there will be very strong shear on the order of 40-50kt as upper trough approaches.
1035 AM CST Mon Nov 21 2016 Warmer with low-level moisture slowly returning through this af- ternoon. This system will bring a cold front across the state Tuesday and Tuesday night.
High pressure will continue to migrate eastward to across the Atlc seaboard.
Although cold fronts will accompany the first three systems, arctic air is not expected to become involved so that temperature variations from day to day are not expected to be overly dramatic. The associated cold front will pass into western Kansas during the morning Tuesday.
Satellite showing a short wave trough rotating south- southeast across northern New York. Ahead of this trough there continues to be a broad plume of lake effect snow over central NY with an upstream connection to Georgian Bay / Lake Huron.
An upper level trough will push the clouds east of the area tomorrow and strong winds rounding the base of the trough will mix into the higher elevations of the Guadalupe Mountains during peak heating.
SHORT TERM (Tonight through Tuesday Night):Low to mid level moisture will return across portions of the state of Texas tonight into Tuesday as a 500mb trough across the southwest United States this afternoon moves eastward across the Rockies tonight into Tuesday.
955 AM MST Mon Nov 21 2016 Also, forgot to mention, added isolated thunderstorms to the grids for this afternoon as thunderstorms are present in the base of the trough over northern Arizona extending into southern Utah. With surface dew points in the 30s and 40s, we will be having a tough time driving the snow levels down until the Pacific trough approaches from the west. As the trough moves overhead tonight, focus of the heaver precipitation will shift from the southern valleys into our central valleys and mountains. Temperatures will be running near seasonal norms today with readings dropping tonight and Tuesday as the main trough swings through.
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.
153 PM MST Mon Nov 21 2016 Also, forgot to mention, added isolated thunderstorms to the grids for this afternoon as thunderstorms are present in the base of the trough over northern Arizona extending into southern Utah. With surface dew points in the 30s and 40s, we will be having a tough time driving the snow levels down until the Pacific trough approaches from the west. As the trough moves overhead tonight, focus of the heaver precipitation will shift from the southern valleys into our central valleys and mountains. Temperatures will be running near seasonal norms today with readings dropping tonight and Tuesday as the main trough swings through.
drifts over the forecast area through tonight and then just E of the forecast area on Tuesday as an upper level ridge moves over. This will keep the forecast dry with less wind than the last couple days and the cooler temperatures will be slow to warm up.
338 PM CST Mon Nov 21 2016 A deep trough is moving east across the Four Corners this afternoon. A downstream ridge over the Plains is slowly approaching, providing northwesterly flow aloft over the Mid- South. High clouds will increase this evening as moisture spills over the top of the ridge. However, farther west, southerly winds will remain up around 5-10 mph which should keep overnight lows above freezing. A few showers and/or thunderstorms may move into the northwest portion of the CWA, mainly west of Jonesboro late tomorrow afternoon as the aforementioned Four Corners trough approaches.
349 PM EST Mon Nov 21 2016 Strong low pressure over southern Quebec is forecast to move slowly northeastward, reaching the Gulf of Saint Lawrence on Tuesday.
1206 PM EST Mon Nov 21 2016 High pressure will build across the region today and Tuesday.
The surface analysis from the national center this morning positions the triple point in southern Alberta with a warm front moving from the southwest across Northeast Montana and a cold front poised over central Montana to follow from the west. So highs today are expected to range from the lower 40s in the northeast to the mid 50s in the southwest. Templer Previous Discussion - 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.
/issued 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.
This Evening Through Tuesday Night Upper trof from OR-NV-wrn AZ will lift northeastward across the central Rockies and Plains tonight. While the low remains well south of the forecast area, an area of precipitation north of the low will spread across Rockies into northeastern WY overnight, while more precipitation ahead of low will clip south central SD, which will continue through Tuesday. Trend of latest models are drier and warmer, so have decreased PoPs over northwestern SD and expect rain showers initially becoming mixed with snow overnight. Forecast soundings show drier air in inversion, so threat of freezing precipitation is diminished. Some patchy fog may form over eastern zones this evening ahead of surface trof, but should dissipate as trof passes and winds switch to the northwest.
A cold front moving from west to east will lower snow levels through the day. Dry and warmer weather will return on Tuesday, lasting through the week. An upper level low is moving from the lower Colorado River Valley into western Arizona this morning with the main band of frontal precipitation spreading across Yavapai and Coconino Counties. Expect areas of winter driving conditions this afternoon through early evening in the high country above 6500 feet.
I adjusted PoPs upward to a slight chance for isolated rain showers moving through the far eastern sections of the Lower Columbia Basin as indicted on KPDT radar returns.
As the center of the high pressure, which is located over southwestern Ontario Canada this morning, moves off to the east, expect the winds to veer to a more southeasterly direction. Otherwise, most locations will stay dry due to the high pressure system overhead. High temperatures will range from the upper 20s to the lower 30s across northeastern MN and northwestern WI. Clouds will be on the increase Monday night as 700-500 mb moisture flux increases ahead of an inverted trough that will bring our next chances of snow during the day on Tuesday. Surface and upper level ridging will move off to the east Tuesday. They are replaced by a long wave trof arriving from the West and an area of low pressure moving through the Central Plains.
On Tuesday, an upper level trough will move in from the west. This will lead to an increasing chance of rain, especially during the evening and overnight hours as a cold front moves into the region. We can't rule out a few strong to possibly severe storms Tuesday evening and overnight for areas generally along and east of the Highway 281 corridor.
144 PM CST Mon Nov 21 2016 Pleasant conditions are expected this afternoon through the Overnight hours as mid level ridging persists ahead of a strong system across Arizona. This will occur as the storm system and low pressure develops and moves into the area. The actual cold front will not push through until late Tuesday night therefore lingering showers will occur Tuesday evening.
324 PM CST Mon Nov 21 2016 The chilly weather of the past couple of days will soon be coming to an end with temperatures rapidly moderating as the ridge of cold high pressure shifts to our the east and southerly winds develop across the region in advance of the next storm system. Since these areas have already experienced two consecutive nights of freezing temperatures with this cold surge, a freeze warning will not be issued and instead a special weather statement discussing the cold temperatures and light freeze will be issued.
Dewpoints are extremely low and will cause rh values to be some of the lowest we have seen through tomorrow afternoon.
300 PM CST Mon Nov 21 2016 1030 mb high pressure over western Ontario and ridging southward across central WI and eastern IL was providing ample sunshine again today to central and southeast IL. High pressure overhead was also providing fairly light winds and seasonably cool temperatures in the low to mid 40s. High pressure will drift east to near the IN/OH border by early Tue morning and continue fair weather over our CWA. Lows overnight will range from the mid 20s in eastern IL to the lower 30s from Jacksonville sw. A vigorous, negatively tilted, upper-level trof, currently pushing into the Four Corners, is the next significant weather feature to impact forecast area.
/issued 1050 AM CST Mon Nov 21 2016/ 12z KLCH sounding came in dry once again this morning, albeit with better moisture in the lowest 100mb or so as expected with the onset of low-level onshore flow over the last 12-18 hours. However all the dry air aloft thanks to the ridging in place from the nwrn Gulf on up through the Plains States will preclude anything other than some fair weather cu development today. Temperatures were just a few degrees above the freezing mark over central Louisiana. Warming trend will begin today as high pressure ridge shifts east of the area.
An elongated inverted trough with mid level WAA will slowly shift over the forecast area this evening. As a result there will be freezing drizzle chances until the that lower layer saturates. Freezing rain is expected to be the main impact for much of the overnight as models continue to showing 850mb temps and wet bulb temps rising to plus 6C then only cooling to 2C to 4C once pcpn starts. Temps aloft very slowly cool from west to east with freezing rain turning to snow Tuesday. Ice accumulations will be up to a tenth of an inch with the higher amounts in the eastern ND and snow totals ranging from 1 to 3 inches in SE ND and the central valley with a 2 to 4 inch range in the northern valley and NW MN.
With a short-lived ridge of high pressure building into the region Tuesday afternoon, expect there to be some sunny breaks ahead of the next system.
244 PM EST Mon Nov 21 2016 High pressure through Tuesday. A weak cold front mid week.
Warmer temperatures are expected this afternoon and tonight as the upper level ridge over the Plains moves eastward over our area, and low-mid level warm air advection increases with low level winds becoming southerly and surface winds becoming southeasterly.
Mid/high clouds set to move in from the west tonight as the upper trof begins to move across the desert SW and into West TX. Models remain on track with the associated cold front with this longwave trof moving into SE TX by Tues evening. These latest runs keeping with the idea that the we will see a rapid return of the cold front as a warm front by Thu/ Thanksgiving evening.
351 PM EST Mon Nov 21 2016 Windy conditions will persist through tonight as a large upper low over New England slowly lifts northeast toward the Canadian maritimes.
Mid/high clouds associated with the developing low pressure system have already started to move into the region this afternoon, and these clouds will continue blanketing the area tonight and tomorrow. Taken together, these factors suggest that overnight lows will be warmer than last night across the entire CWA with a noticeable gradient from west to east. The eastern CWA (parts of southwestern IL) will experience lighter winds, less thick cloud cover, and a drier air mass for a longer period of time compared to the western CWA (parts of central MO), which is closer to the developing low pressure system. Therefore, overnight lows should be several degrees cooler across southwest IL compared to central MO.
High temperatures will be cooler than normal today with near normal temperatures and clear skies expected much of this week.
144 PM CST Mon Nov 21 2016 Pleasant conditions are expected this afternoon through the Overnight hours as mid level ridging persists ahead of a strong system across Arizona. This will occur as the storm system and low pressure develops and move into the area. The actual cold front will not push through until late Tuesday night therefore lingering showers will occur Tuesday evening.
Lows will fall into the lower 30s inland, with mid to upper 30s closer to the coast.
A cold front will move from northwest to southeast through tomorrow afternoon into the evening. The cold front will provide a mechanism for strong, linear forcing.
While the low-level southeasterly winds will keep the lower levels of the atmosphere dry on Tuesday, higher level cloudiness, associated with the developing Plains low, will overspread the area tonight into Tuesday, resulting in mostly cloudy conditions on Tuesday.
The continual presence of the dendritic growth zone at the top of the saturated layer will keep snow showers continuing through the afternoon into the evening north of Pittsburgh and into the Ridges. 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.
245 PM MST Mon Nov 21 2016 Shower activity will taper off this evening with clearing skies and much cooler temperatures tonight. The upper low is centered over northwest AZ early this afternoon with a vort max tracking across Maricopa and Yavapai Counties. As the low center and the vort max continue to pull away from the forecast area, this activity will trend down. Only a slight chance of lingering showers tonight over the higher terrain. Look for much cooler overnight temps tonight.
/issued 953 AM CST Mon Nov 21 2016/ The mid/upper-level ridge axis remains to the west today, resulting in northwesterly flow aloft over the Mid-South. The surface anticyclone will gradually slide off to the east over the next 12-24 hours, with southerly flow resuming across the region. Winds will remain light today, with temperatures ranging from the low/mid 50s over northwest TN to the lower 60s across north MS and the Memphis metro area. High pressure prevails across the region. Clear skies and light winds are creating good cooling conditions and temps range from the mid 20s along the TN River to the lower 30s in the Delta with a few hours of cooling left. High pressure slides slowly east during the period. Low pressure will be moving through the Plains on Tuesday with a cold front pushing through the southern Plains.
NW flow aloft will prevail over central NC through tonight, between a potent /mature/ upper low situated downstream over New England and an amplified upper level ridge situated upstream over the Great Plains. Expect clear skies with highs ranging from the upper 40s near the VA border to the low/mid 50s near the SC border, based on local 1000-850 mb thickness research. Expect clear skies /dry conditions/ and light/variable winds with temps a few degrees warmer than today (in the 50s) and lows Tuesday night similar to (or perhaps a degree or two warmer than) tonight, in the mid/upper 20s to lower 30s, particularly if sct cirrus is present prior to sunrise. -Vincent The upper trough that's currently over the Southwest US will advance east across the Central US Tuesday-Tuesday night.
321 PM CST Mon Nov 21 2016 A compact upper low is moving quickly across Arizona this afternoon. The warm conveyor belt downstream of the low has brought a plume of mid-level moisture and a band of light rain showers progressing across central and eastern New Mexico, and on into West Texas at 3 pm. The upper low will continue its northeast trek tonight into southeast Colorado by early Tuesday morning. But as the low approaches later tonight, we could see another round of showers late in the evening, as some of the short-term guidance suggests. As the upper-low quickly moves across the central plains Tuesday, the trough axis and dry front will sweep across West Texas, with gusty westerly winds developing during the day.
With surface dew points in the 30s and 40s, we will be having a tough time driving the snow levels down until the Pacific trough approaches from the west. As the trough moves overhead tonight, focus of the heaver precipitation will shift from the southern valleys into our central valleys and mountains. Temperatures will be running near seasonal norms today with readings dropping tonight and Tuesday as the main trough swings through.
A very dry airmass was allowing temperatures to rise quickly into the 40s across the lower elevations south and mid to upper 30s northeast areas.
1050 AM CST Mon Nov 21 2016 12z KLCH sounding came in dry once again this morning, albeit with better moisture in the lowest 100mb or so as expected with the onset of low-level onshore flow over the last 12-18 hours. However all the dry air aloft thanks to the ridging in place from the nwrn Gulf on up through the Plains States will preclude anything other than some fair weather cu development today. Temperatures were just a few degrees above the freezing mark over central Louisiana. Warming trend will begin today as high pressure ridge shifts east of the area.
Satellite imagery clearly shows a small rotating low pressure disturbance moving northeast through southern Saskatchewan this afternoon. This disturbance will send a weak cold front through Northeast Montana tonight. a broader upper trough then moves across our region on Tuesday. Additional cloud cover from the trough and a slight northwesterly breeze with make not make for a mild day like we have been having.
The NAM and GFS were both in good agreement with moisture and instability improving in the 700mb to 500mb level overnight ahead of an upper level trough that will be crossing southwest Kansas during the overnight hours. On Tuesday a surface cold front will cross western Kansas early in the day. Highs on Tuesday are still expected to climb into the 50s across southwest Kansas early, however once the cold front passes these temperatures will begin to fall back into the 40s as the gusty northwest wind develop.
118 PM EST Mon Nov 21 2016 High pressure 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.
234 PM EST Mon Nov 21 2016 Another clear and cool day as the Ohio Valley remains under dry high pressure. However, tonight will be another cold one as the ridge keeps skies clear and winds light. Mins will generally run only a couple degrees warmer than last night, as the better return flow remains limited to western Kentucky. Tuesday night we get onto the backside of the upper ridge as a progressive trof pushes into the Plains, and the southerly surface gradient tightens. Still think the low levels will be slow to moisten up, as that southerly flow is coming off some drought- ravaged areas in the Deep South, and the Gulf tap isn't very deep.
High pressure will keep conditions dry through the start of the work week.
Expect VFR conditions to prevail this afternoon and evening even as subsidence begins to diminish across south Texas as the 500mb ridge across the central United States moves eastward and moisture begins to increase ahead of the the 500mb trough across the southwest United States. /issued 349 AM CST Mon Nov 21 2016/ 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.
54", with only a few clouds over the warmer Gulf Stream. Temperature will remain a few degrees below normal, peaking out in the low-mid 70s later this afternoon. This cooler, drier air will be the major player for weather in South Florida through much of the week.
1059 AM CST Mon Nov 21 2016 Few cirrus and a nice southerly breeze rebounding temperatures into the lower 60s already.
341 PM CST Mon Nov 21 2016 (Tonight and Tuesday) An upper level trough over the Great Basin will move east across the southern Rockies and into the Central and Southern Plains on Tuesday. Given the extent of cloud cover and an increase in low level moisture overnight, temperatures will be considerably warmer, with lows in the mid and upper 50s. Could see a few showers or a thunderstorm develop over far southeast counties ahead of the trough axis but due to limited moisture and upper level support, will limit POPs to 20 percent. (Tuesday night through Monday) A cold front will move through the area Tuesday evening, resulting in gusty north winds and cooler temperatures.
234 PM EST Mon Nov 21 2016 Windy conditions will persist through tonight as a large upper low over New England slowly lifts northeast toward the Canadian maritimes.
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.
Southeast to south flow will develop on Tuesday as the surface and 850 mb ridge pull to the east. Lows in some of our notorious cold pockets may dip into the 30s, but most other areas should stay in the lower to middle 40s.
247 PM EST Mon Nov 21 2016 The area remains between large low pressure over the northeast and ridging in the Midwest which is continuing the fresh northwest flow of cold air. High pressure to the west will slide eastward and be centered overhead during the day Tuesday.