Aikyam-Lab/Synoptic-Bench huggingface dataset:
Freezing fog is possible where temperatures fall below freezing. The combination of fog and temperatures at or below freezing may create slick spots on the roads. Additionally, with temperatures at or below freezing in many of these locations-we could see slick spots develop on the roads due to patchy freezing fog. Modified sky coverage grids significantly higher over blend with some breaks, especially northwest CWA towards daybreak as saturated layer thins amid persistent downward vertical motion and start of dry air advection within return/southerly flow as centroid of ridge moves into central OH by daybreak.
High pressure today will keep the area dry and clear with high temperatures mainly in the 60s. By tonight clouds will be streaming back into the Midsouth ahead of the next cold front, keeping overnight lows in the 40s. The aforementioned cold front will traverse the Midsouth on Wednesday, but it will have little impact on temperatures due to the lack of any appreciable cold air mass.
Temperatures are warming through the 40s and 50s and in some areas into the low 60s. Behind a cold frontal passage on Tuesday, it's debatable whether or not an isolated shower or two may be working its way east-southeastward across the cwa. A couple models are hinting at temperatures warming the most on Tuesday once the surface cold frontal passage occurs and better northwesterly mixing winds establish.
1137 PM CST Mon Nov 13 2017 The forecast area was between exiting high pressure near the lower Great Lakes, and developing low pressure in the lee of the Rockies in Wyoming. Weak warm air advection was occurring ahead of the low. There is a very small chance of some freezing drizzle over northwest Wisconsin. The southwesterly flow continues Tuesday ahead of the low pressure system that has formed over the Canadian prairies. Some drizzle is possible ahead of the front, with the freezing drizzle over the eastern edge of the Wisconsin forecast area in the morning.
Trof movg across the Great Lakes region Wednesday will bring a cold front into our nrn areas, but the upper ridge over the Desert SW will dampen the influence of the trof and cause the front to stall.
What happens overnight into Tuesday as the ridge moves east is the main question during this part of the forecast. Expect areas of fog and low clouds to reach central and north central Wisconsin during the night, and freezing drizzle is possible during the late night and into Tuesday morning. The NAM is likely overdoing the low level moisture, leading to lower forecast confidence, so have opted to downplay freezing drizzle a little and not issue an advisory. Any freezing precipitation will switch to liquid on Tuesday as temperatures increase due to warm advection. Lows tonight have been adjusted upward due to increasing clouds and warm advection, and highs on Tuesday should be warmer than today.
The combination of subsidence beneath this upper ridge and dry northeast surface flow means we stay mostly sunny and rain free into midweek. Temps stay right around their seasonal averages, with lows tonight in the low 40's inland to upper 40's along the coast, and highs Tuesday in the upper 60's to low 70's.
236 AM MST Tue Nov 14 2017 Dry weather with periods of high clouds will persist this week as high pressure remains over the region or situated just to our south. A storm system passing to the north later in the week could bring slightly cooler temperatures and some breezes to the Southwest. Latest upper level analysis shows a broad area of high pressure just to our south over the Eastern Pacific and Mexico and is responsible for the unusually warm weather we have been seeing. To our north, a trough of low pressure is positioned over the Pacific Northwest and continues to bring showers and cool weather to the area. 500 mb heights will gradually lower today and through this week as the aforementioned high pressure weakens and the Pacific trough digs further south and east.
Southerly flow will continue to increase ahead of this area of low pressure with a weak upper level disturbance moving through the region currently. WAA and moisture advection continues ahead of this boundary, with soundings showing deep saturation in the lower levels through late Tuesday.
Cold front will move across the area Wednesday morning bringing an end to the showers.
/Today through Tonight/ Good southerly flow has developed across Iowa with high pressure to the east and trough of low pressure approaching from the west. The low level moisture advection will strengthen through the day with dew points rising into the mid 40s to lower 50s by mid to late afternoon. Best potential for widespread precipitation will be between 03-09z before a cold front and drier air move into central Iowa.
A little freezing drizzle is possible over north-central Wisconsin early this morning before temperatures warm above freezing. A cold front approaches late this afternoon from the west and will move through during the overnight hours into Wednesday morning.
This activity should fade in the afternoon and much of the evening before a more widespread and substantial rainfall event takes place ahead of a cold front late Tuesday night. Overnight min temps tonight will range from near freezing in parts of southwest IL to the low-mid 40s in MO underneath thicker cloud cover and a more southerly low level flow. Only modest increases in temps into the low 50s on Tuesday with most locations continuing under mostly cloudy skies. TES High pressure at the surface quickly moves off to the east overnight. Clouds should temper temperatures a bit for tomorrow, but will still be warmer than today for most areas. A southwesterly low level jet Tuesday night will bring increasing low level moisture into our region ahead of the approaching cold front.
A system moving north of the area will bring cooler temperatures late in the week, but still above average. Near record temperatures again today as unseasonably strong high pressure nosing in from northwest Mexico continues to dominate our weather. Some model differences between the GFS and ECMWF on how deep the cooler air and how long to sustain it, as the ECMWF ensemble mean has been consistently and increasingly slower with the trough axis progression than the GFS.
309 AM EST Tue Nov 14 2017 High pressure builds in from the northwest today and Wednesday, keeping conditions cool.
In addition, some patchy fog will be possible late tonight and early Tuesday, mainly in the low-lying areas and river valleys. Temps are a bit below normal under a cool NE breeze with readings ranging from around 50 along the KY/MO borders to the lower to mid 60s across parts of North Mississippi. Temps will be slightly warmer on Tuesday with a plenty of sunshine. Will start to see increasingly clouds Tuesday night as the next cold front approaches.
Even into Tuesday, the low level moisture does not move out of the area until after noon. There are a few mainly weak upper level waves that move through the area and bring weak cold fronts through the area. The first of the weak waves and cold fronts will be Tuesday night and that will keep temperatures on Wednesday from being very warm.
Surface trof will reach AMA and GUY by 15z, with drier air causing ceilings to dissipate. Surface trof currently over eastern New Mexico will move eastward into the Texas and Oklahoma Panhandles on Tuesday, taking on dryline characteristics by noon. The cold front is still on schedule to push through the area Tuesday night into Wednesday morning, which will lower temps 10 to 20 degrees on Wednesday into the 60s.
Although shifting to the northeast, high pressure will remain wedged into the forecast area over the next 24 hours. This shift will cause winds across the CWA to be more east northeasterly today, in addition to conditions being a touch warmer. However, towards day break Wednesday, some clouds will begin working their way into the Delta due to increasing moisture and upglide ahead of a cold front that should be dropping southeast into the Ozarks.
Meanwhile a weak cold front will move to near the I-20 corridor around 15Z/Wed. Even though it will be warmer Thur PM mstr will not be scoured out, except in Davis/GDP Mtns/Eddy Co. This will all be ahead of a stronger cold front that will move thru late Fri night and thus cooler wx will be the rule Sat AM-Mon PM.
Currently, a thick canopy/cirrus shield is rapidly moving from west to east across North Dakota, and will essentially block the viewing of the lower clouds overnight. At the same time, the first of two cold fronts will enter western ND around 10z Tuesday, and quickly make its way through central ND by 15z Tuesday. Otherwise, the second cold front will push through Tuesday evening/night. The area of fog potential should be further north and east than the last night with the strong warm advection at h850 dominating the low level temperature profiles across southwest and south central North Dakota resulting in less fog potential.
Overnight temperatures will be very mild for mid November with lows mainly in the lower 60s. 79 Another cold front will move into North Texas on Wednesday once an upper trough swings through the Central Plains.
325 AM EST Tue Nov 14 2017 High pressure will continue to build into the area today and remain in control through the short term. By the end of the short-term period Wednesday evening, a weak cold front will be pushing into middle Tennessee but will be increasingly moisture starved as it approaches Georgia.
Dry weather will stay in place over central Indiana until early Wednesday morning when a low pressure system approaches from the west, bringing rain to the area through the day on Wednesday.
/Issued 258 PM EST Mon Nov 13 2017/ High pressure will continue to build into the area from the north through the short term. The upper level trough is currently pivoting across the region with subsidence flow on the back end. Low temperatures will be a couple degrees below normal with mid/upper 30s in the high elevations to mid 40s toward south GA. The high will begin to build south into north/central GA through the day. Highs will climb close to 60 degrees across the higher terrain to the mid 60s in central GA. Tuesday night should be quiet weather-wise as mid/upper level ridging builds into the region. Lows again, below normal in the upper 30s/low 40s area wide; cooler across far northeast GA.
Despite the cirrus, with low clouds gone temperatures should drop well into the 30s overnight for much of the area, although temperatures could be much warmer if and where any low clouds linger across northern counties. Another cool, dry day is on tap for Tuesday with temps warming into the 50s to near 60, with lows a bit warmer Tuesday night in the 30s and 40s. Our next rainmaker in the form of a weak cold front will bring another round of showers to the area from Wednesday afternoon into Wednesday night, although rainfall totals look to be quite light at only around a tenth of an inch or so.
929 PM MST Mon Nov 13 2017 Primarily zonal flow is prevailing under a flat ridge of high pressure, with warmer temperatures than seen yesterday due to lack of dense cloud cover. Temperatures will remain about 10 degrees or so above normal with cooler overnight lows near or slightly above normal.
350 AM EST Tue Nov 14 2017 High pressure over the Ohio Valley will drift southeastward and extend across southern Virginia and the Carolinas Tuesday night and Wednesday.
A dry cold front will move in from the northwest bringing a northerly wind shift to the northern parts of the area during the late afternoon.
The HRRR, NAM, and RAP soundings show that the low level moisture will increase into the 1 to 2 km range by late evening and then continue into Tuesday. This provide up to a 3 hour period in which freezing drizzle may occur before the temperatures and dew points rise above freezing; thus, ending the icing threat. The highest potential for any icing will be in Clark, Jackson, and Taylor counties. Thought about issuing a Winter Weather Advisory for this freezing drizzle threat, but the threat is such a short period decided to go with a Special Weather Statement instead and monitor how things evolve. Besides the freezing drizzle threat, another potential threat will be the development of dense fog. The final concern for tonight is whether we are too cold with the low temperatures along and west of the Mississippi River.
At the surface, lee troughing continues to increase across eastern CO/western KS allowing strong moisture advection to remain over the central Plains. Cold front will be south of the forecast area by 15z Wed, but airmass behind the front still doesn't look that cold, with near normal highs anticipated. This will again result in lee troughing strengthening and the central Plains quickly getting back into a low level moisture advection pattern like we have already seen several times this month. The GFS remains faster with this feature compared to the ECMWF and thus also pushes the cold front through faster. The passing of this wave is expected to commence a pattern change with more pronounced upper riding setting up over the Rockies and sharp troughing over the northeast CONUS.
Patchy drizzle or light rain remains possible across southeastern portions of our CWA Tuesday morning in warm-air advection regime with a better chance over the same area later Tuesday night as a cold front begins to sweep through the CWA. Clouds should clear fast behind the cold front into Wednesday morning.
Strong high pressure ridging at the surface will prevail tonight with cold temperatures ranging from the mid 30s in the northeast, to the mid 40s in the south. Upper ridging will strengthen over the region on Tuesday, and this will allow for clear skies and slightly warmer afternoon highs in the upper 60s to around 70 over the area.
226 AM MST Tue Nov 14 2017 09z surface analysis showed low over southeast MT with modest pressure falls across the northern Plains ahead of cold front pushing across central MT. Ahead of it across southwest into central SD, temperatures will reach the lower to mid 60s with 50s to the northwest. Wednesday, cooler temperatures expected as upper ridge builds to our west.
A more substantial warm up will occur later in the week in advance of an approaching upper level trough and associated cold front.
1154 PM MST Mon Nov 13 2017 Upper ridge cresting over northern Plains this evening with a thick band of cirrus moving over forecast area ahead of upper trof along Pacific coast. Lee trof along front range of Rockies-Big Horn Mtns has southerly winds ahead of it. Trof will cross forecast area after midnight, with cool front entering northwest SD early Tuesday morning.
Lows look on track to bottom out in the low to mid 30s. Models forecast some clouds to move back into the area tonight, but probably will be mostly higher clouds as the lower clouds should move back into the area beginning Tuesday morning. However, the next weather system will be moving toward the area tomorrow as the high pressure continues to slide to the east.
Both ATY and ABR have fluctuated between 2SM and 1/4SM vis over the past couple of hours, with the latest values in the lower range. Temperatures are warming through the 40s and 50s and in some areas into the low 60s. Behind a cold frontal passage on Tuesday, it's debatable whether or not an isolated shower or two may be working its way east-southeastward across the cwa. A couple models are hinting at temperatures warming the most on Tuesday once the surface cold frontal passage occurs and better northwesterly mixing winds establish.
Temperatures across the western CWA should get into the mid to upper 50s, with more abundant sunshine in the afternoon, while temperatures reach the lower 50s near the Indiana border.
Nevertheless, temperatures in the low to mid 30s and light winds should support considerable frost development over the northeast two thirds. Slightly warmer high temperatures look probable with upper 50s and 60s. evolving nor'easter will be responsible for carving out a large E Conus trough and that will serve to keep the cold airmass entrenched over our region for a few days. The result of this will be a few more opportunities to see near/below freezing conditions. Look for a quick warmup for later week with more moisture and warmer temps slated for the weekend. A warmer suite of guidance was preferred each of those days. Some 80 degrees readings were added to the forecast highs on Sun-Mon, but if more sunshine can peak out between clouds and some chances for rain, then warmer readings will verify.
/issued 629 PM CDT Mon Mar 12 2018/ Deep upper level troughing will persist across the eastern half of the United States through mid week.
529 PM MDT Mon Mar 12 2018 Latest upper analysis shows a high amplitude upper ridge over the western CONUS with a weak vort max dropping down the east side of the ridge, currently moving from swrn SD into nwrn NEB. At the surface a N-S oriented band of high pressure over the great plains will lead to light southeasterly winds over much of the forecast area tonight.
Surface wise, an expansive region of high pressure is centered over the upper Great Plains states with a ridge reaching southeastward to the Gulf coast region, and into our area. In wake of the cold front which cleared our area late this afternoon and early this evening, strong subsidence will result in patches of mid and high level cloudiness skies with low temperatures dropping into the upper 50s in the Upper Keys to the lower 60s in the Lower Keys.
Cold air advection in the wake of the front will support a noticeably cooler night with overnight lows falling into the mid and upper 30s across the Nature Coast, lower to mid 40s central and southern interior locations, and upper 40s along the Gulf coast by early Tuesday morning. High pressure building in over the region will allow lighter winds and seas to return to the waters on Tuesday and continuing through the remainder of the week.
901 PM CDT Mon Mar 12 2018 High pressure building into the region will keep skies mostly clear and winds light overnight. The combination of clear skies and light winds will be supportive of radiative cooling during the overnight hours while the high pressure is over the region.
The expected low pressure system is generally performing as expected for now, with showers not moving into the area until Tuesday afternoon.
1040 PM CDT Mon Mar 12 2018 A longwave upper-level ridge over the Western CONUS will keep active weather out of the near term forecast period. Due to the relatively dry north winds the incoming airmass is not overly moist; however, the favorable radiational set-up looks supportive for at least patchy fog for much of the James River Valley and the Buffalo Ridge. Fog should dissipate by mid-morning as sunshine helps mix the lowest layers of the atmosphere.
No further changes were needed for the late eve update as scattered snow showers, numerous in the ridges, can be expected tonight as cold upper low pressure entrenches over the region. With little organizational support and an initially warm ground, significant accumulation is not expected off the ridges. Will keep PoPs in the high chance range, but everyone should see flakes at some point during the day.
919 PM EDT Mon Mar 12 2018 An upper level low moving across the Great Lakes into the Northeast will bring below normal temperatures and scattered snow showers into Tuesday night. Temperatures are starting to drop down to around freezing but road temperatures still look to be quite a bit above freezing so am not anticipating too much of a problem on roadways. While this activity will produce little snow accumulation, it can have a big impact on travel conditions, especially if road temperatures remain near or just below freezing as expected as this precipitation moves through. Favored cooler guidance for Tuesday highs while a MOS blend seemed reasonable for Tuesday night lows. An upper level low pressure will be centered across the northeastern United States with the ILN forecast area in the ageostrophic convergent side of the trough axis.
/issued 929 PM CDT Mon Mar 12 2018/ Clear skies and high pressure settling in at the sfc will make for a chilly night across the ArkLaTex.
An upper low and trough are slowly moving towards the Pacific Northwest coast this evening. The low and a front is evident on water vapor imagery and radar is showing some returns beginning to appear over Northern California.
708 PM EDT Mon Mar 12 2018 Precipitation will end this evening as an upper level low pressure system over eastern SC moves off the coast. Cooler and drier air will enter the region tonight behind the system.
/issued 303 PM CDT Mon Mar 12 2018/ Deep upper level troughing will persist across the eastern half of the United States through mid week.
GAH PREVIOUS SHORT TERM DISCUSSION: With an amplified ridge moving into the region overnight and Tuesday, skies will remain clear with little to no wind. Still expect increasing temperatures over the next couple of days with the ridge moving through the area.
959 PM MDT Mon Mar 12 2018 Dry high pressure will be over Wyoming tonight and Tuesday.
the associated upper low will track through to our north and will bring in wrap around moisture and weak lift for scattered light upslope snowfall tonight. Chattanooga Airport, TN 32 51 30 49 / 10 0 0 0 Knoxville McGhee Tyson Airport, TN 31 46 28 44 / 20 0 10 10 Oak Ridge, TN 31 47 27 44 / 20 0 10 10 Tri Cities Airport, TN 28 42 25 39 / 20 10 40 20 TN.
746 PM EDT Mon Mar 12 2018 An upper level low moving across the Great Lakes into the Northeast will bring below normal temperatures and scattered snow showers into Tuesday night. However, clouds are expected to increase again late as the next impulse drops into the mean upper trough. While this activity will produce little snow accumulation, it can have a big impact on travel conditions, especially if road temperatures remain near or just below freezing as expected as this precipitation moves through. Favored cooler guidance for Tuesday highs while a MOS blend seemed reasonable for Tuesday night lows. An upper level low pressure will be centered across the northeastern United States with the ILN forecast area in the ageostrophic convergent side of the trough axis.
Minor trough entering southern Illinois and southwest Indiana as of 9 pm. Tonight, low clouds are likely to diminish as high pressure continues dropping south into the Plains. Stratocumulus clouds once again increasing again, esp east areas, as an upper low drops into the upper Ohio Valley.
929 PM CDT Mon Mar 12 2018 Clear skies and high pressure settling in at the sfc will make for a chilly night across the ArkLaTex. It will quickly move southeast down the back side of the trough over the next 24 hours, bringing us a few more clouds tomorrow. Expect most places to be similar to or just slight warmer. At this point in time, do not think we will see a widespread freeze, but some of the colder locations across southeastern Oklahoma and southwestern Arkansas will definitely be flirting with or seeing the freezing mark. High pressure will then build across the region for the remainder of the work week, with warmer and more seasonal conditions prevailing.
1041 PM MDT Mon Mar 12 2018 Latest upper analysis shows a high amplitude upper ridge over the western CONUS with a weak vort max dropping down the east side of the ridge, currently moving from swrn SD into nwrn NEB. At the surface a N-S oriented band of high pressure over the great plains will lead to light southeasterly winds over much of the forecast area tonight.
1024 PM EDT Mon Mar 12 2018 Cooler and drier air will overspread the region tonight as a low pressure system off the NC coast moves north.
615 PM CDT Mon Mar 12 2018 Tonight, low clouds are likely to diminish as high pressure continues dropping south into the Plains. Stratocumulus clouds once again increasing again, esp east areas, as an upper low drops into the upper Ohio Valley.
Large scale trough over the Great Lakes region is producing northwest flow over central IL with a series of embedded weak disturbances bringing a threat of flurries and sprinkles over the upcoming day.