Aikyam-Lab/Synoptic-Bench huggingface dataset:
306 AM CDT Sun Apr 8 2018 Water vapor imagery shows a series of upper impulses about to move out into the high Plains. At the surface, lee troughing extends from eastern WY through eastern CO. Precip type will be a challenge this morning as the low layers remain very dry. This means that much of the area will be hovering right near the freezing mark as precip falls. The good news is that the dry low layers should keep any wintry precip on the low side. Models agree that one last piece of energy is expected to rotate through the trough on Mon. Medium range models still agree on digging a deep trough over the Great Basin on Thu which will further ramp up return flow and warmer temps across the region.
Rain and mountain snow showers increased in coverage overnight in response to a decaying trough moving into the region. Most of the precipitation today remains focused in north-central Idaho and in the high terrain of western Montana. Showers will linger into tonight, but high pressure should put an end to most of the showers during the day Monday. Drier and warmer conditions are anticipated for Monday afternoon.
Light precipitation chances then return for Monday with a trough of low pressure. An upper trough is progged to cross the Eastern Great Lakes and Upper OH Valley region this morning, resulting in a stratocu layer. The stratocu should gradually erode after the passage of the trough. High pressure should maintain dry weather through much of tonight as it slides E.
A cold front will then move thru mostly after 03Z.
139 AM EDT Sun Apr 8 2018 A low pressure system and cold front will cross the area this evening.
The low levels of the atmosphere will gradually saturate with precipitation breaking out at least across northeast and central MO and west central IL later this afternoon. May be some lingering flurries or patchy freezing drizzle across parts of northeast MO and west central IL late tonight. With still some uncertainty as to exact precipitation amounts, precipitation types, and not as much impacts on roads due to air temperatures initially being above freezing coupled with warm road temperatures will hold off issuing a winter weather advisory at this time.
/NF/ Prior discussion below: Tonight through Sunday: The primary concerns tonight will be shower and thunderstorm chances late this afternoon into early this evening, and then the potential for freezing temperatures later tonight into early Sunday morning. Expect sunny skies to allow for much more comfortable conditions by Sunday afternoon as weak high pressure becomes centered over the area.
Meanwhile, downstream pattern consist of an amplifying trof over the cntrl/ern CONUS. strong high pressure was in control over the central CONUS. Expect a transition to a snow/rain mix during the aftn hours as MaxT aloft climb above freezing.
High pressure moving in from the west will raise temperatures through mid week before a potent system later this week brings strong winds, cooler temperatures and a chance of precipitation to parts of the area.
1108 PM MDT Sat Apr 7 2018 Current surface analysis shows high pressure over the eastern Dakotas, with low pressure across northern ID. Upper level analysis shows a weakening ridge over the Northern Rockies, with a large upper low off the Pacific NW coast. However, warmer air aloft will be advecting into the area tonight ahead of the low and could bring some light freezing rain from portions of western to south central SD late tonight/early Sunday. Behind the low, gusty northwesterly winds will develop in many areas for the late morning and afternoon.
Temps should continue to fall into the low to mid 20s across the region and the Freeze Warning remains in effect. With temperatures right at or slightly above freezing this should have little impact.
Temperatures are expected to be about ten degrees below seasonal normal for the highs.
There were isolated reports of sleet or freezing rain, but no ice accumulations were reported as road surface temperatures warmed well above freezing by late afternoon. Expect the precipitation to generally end by early Sunday, with warmer air moving into the region.
A cold front is expected to move through each terminal starting with KGUY around 16Z. /Issued 423 PM CDT Sat Apr 7 2018/ Mid levels indicate strong ridging today in the west with a strong closed low coming onshore in the Pacific NW. This will bring a cold front through the area between late morning and early afternoon from north to south. By the beginning of the work week the mid level ridge re-strengthens, but another wave pushes through the main flow in the wake of the low's breakdown. Thus a second cold front is progged to come through the Panhandles Monday.
Farther south, the RAP and HRRR remain dry into southern Iowa but they seem to be keeping the low levels much too dry. The higher precipitation rates in the south will likely be associated with snow and lighter rates with sprinkles or very light rain. For tonight, the upper low will drift southeast toward the state with relatively good forcing persisting across much of the forecast area. 5" along the Highway 30 corridor.
and Monday After another record breaking morning across the area, high pressure will slide east as daytime highs improve into the lower to middle 30s across the region. Skies will start out sunny this morning, with increasing clouds from west to east throughout the day as a low pressure system approaches the area.
as most areas within the CWA have dropped to around or below freezing so far. Will keep the Freeze Warning in place through 09Z this morning when temps will warm above freezing for most areas. Will be keeping a close eye on this trend to see if a Freezing Fog Adv may be needed if it becomes more widespread this morning.
While surface temperatures will initially be in the lower 40s, dewpoints in the teens will allow enough evaporational cooling to occur as precip commences to quickly lower the temp and transition the precip to snow.
419 AM CDT Sun Apr 8 2018 Upper level trough that brought a cold front and thunderstorm activity to the area yesterday is now east of the area and headed towards the Atlantic coast. Showers will continue lingering across coastal parishes in response to previous cold front gradually lifting back north towards the northern Gulf Coast.
A cold front will move across the region tonight through Sunday morning.
242 AM EDT Sun Apr 8 2018 Drying will occur this morning with low pressure moving farther northeast and high pressure moving into the region in its wake. Moisture will increase tonight in an easterly flow and ahead of low pressure south of the area.
A ridge of high pressure will provide fair skies across the region tonight through Monday with warming temperatures early in the week.
657 AM EDT Sun Apr 8 2018 Low pressure passes well east of New England today. High pressure will follow on Monday.
Highs today will range from the lowers 70s to near 90. For tonight, another weak cold front will push into West Central Texas.
This is in association with a baroclinic zone passing across northern Kansas as an upper level trof moves across the greater region. Fire weather conditions look marginal today and the most favorable conditions will be near the Colorado border, where it will be warmer.
Mainly quiet weather is expected through the short term period as upper level ridging briefly builds over the region.
/26/ Today and Tonight: Latest observational data showing the far northeastern areas have managed to drop to the freezing mark, while further west reading were just above. Thereafter, veering low level winds as high pressure center moves off to the east will begin to bring low level moisture and cloud cover back into the area from the southwest. Model soundings seem to indicate moisture depth with the weak ascent will be sufficiently deep for patchy drizzle in proximity to this low pressure feature which will exit to the east before sunrise Monday.
/issued 338 AM CDT Sun Apr 8 2018/ High pressure over the Mid South today will slide east with weak return flow setting up.
High pressure will be attempting to near from the north, but another weak trough will keep a small mention of snow in the forecast overnight.
628 AM EDT Sun Apr 8 2018 Upper air pattern consists of a 500 mb trough over the lower Great Lakes this morning with a closed low off the Pacific NW coast. Broad upper level troughing with continuation of colder than normal temperatures looks to prevail much of the upcoming week. High pressure in wake of that system will bring dry weather Thu, then medium range models and ensembles continue to point to potential for large winter system affecting the Upper Great Lakes region Fri into Sat. Both blend of model qpf along with ensemble probabilities for exceeding over 1 inch of qpf point to potentially a significant system, though potential for warm layer aloft (shown by latest GFS and ECMWF) will ultimately determine extent of snow and/or sleet/freezing rain.
Otherwise some snow will continue over the higher mtns overnight. QPFs continue to drop off but should still see another 4-7 inches on the higher peaks so continued the winter wx advy there. Warmer tomorrow as the cold surface airmass continues to move out with downsloping flow. Monday looking mainly dry and a bit cooler with some breeziness under decent mid level nwly flow.
635 AM EDT Sun Apr 8 2018 Upper air pattern consists of a 500 mb trough over the lower Great Lakes this morning with a closed low off the Pacific NW coast. A general/steadily reinforced upper-level troughing pattern will continue to linger across much of the eastern CONUS through much of the upcoming work week.
This weakening manifests itself in many ways, but the biggest impact is the expected weakening of the LLJ to the east of the low. Because of this weakening, any deviations from the current forecast will likely be in the lower as opposed to higher direction.
Much of our nrn areas are currently experiencing temps very near or just below the freezing mark, and a Freeze Warning will remain in effect for these areas through 8 AM.
312 AM MDT Sun Apr 8 2018 Upper level analysis has a low off the Pacific Northwest Coast with weak ridging over the High Plains and a large scale trough extending from the Great lakes area down through the Mississippi Valley. At the surface, an area of low pressure is located across eastern Wyoming, with a frontal boundary extending northwestward through western Montana, and a lee trough extending southward along the Front Range of Colorado. High temperatures today will range from the lower to mid 30s across northwestern South Dakota to the mid and upper 40s across northeastern Wyoming and southwestern South Dakota. Overall, precipitation will be light, but wouldn't be surprised if the higher hills picked up an inch or two of snow. On Monday, an upper ridge over the western CONUS will begin to build into the area.
This should limit snowfall as precipitation will more likely be mixed and will be difficult to accumulate with surfaces being warm as well as temperatures being above freezing. model soundings suggest that we lose ice crystals in the snow growth zone which would result in a period of light freezing drizzle. Fortunately, any snow that does accumulate will surely be gone by Monday as a cold front providing weak cold air advection behind it will allow highs to rise into the low 40s to near 50.
324 AM PDT Sun Apr 8 2018 High pressure will build in over the region from the west today and move into the great basin by Monday.
High pressure is moving across the central sections of the country with the ridge expected to be centered over the Ohio Valley by this morning. A ridge aloft is centered over North Mexico and will also build east through today. The ridge aloft over Mexico will build in and exit east through tonight.
110 AM EDT Sun Apr 8 2018 A quiet and cold weekend is expected as high pressure builds into the region.
Upper trough was working across eastern Montana this hour.
A cold front will then move thru mostly after 03Z and included the general FROPA at end of TAF period. A fast WNW flow aloft along with deep sfc lee side troffing will allow temps to soar this aftn. therefore the High Wind Watch has been upgraded to a Warning for this aftn/early evening.
311 AM EDT Sun Apr 8 2018 High pressure will provide mostly sunny skies and light winds today. Temperatures however will remain cool with highs generally in the low 40s. Chances for light snow and rain will return later tonight through Monday night as a weak low pressure system moves through.
A ridge of high pressure centered over the Mississippi valley this morning will move northeastward through the day. To our south lies the stalled remnants of yesterdays cold front. As the ridge lifts northeastward, the front will lift back northward into our coastal waters area this afternoon.
As a result, radiational cooling was taking more effect and temperatures were dipping into the lower to middle 30s. With the upper trough shifting east, 5h flow will become more zonal in nature today. This along with the plentiful high level moisture streaming off the Pacific associated with the next trough will bring mid and high clouds rapidly back into the area this afternoon into tonight. The clearing sky should allow temperatures to rebound into the lower to middle 60s during the afternoon hours.
Forcing with this trough will bring a chance of rain to the area tonight, starting around midnight as the 850-700 mb flow turns S-SW and isentropic lift strengthens. The trough moves through quickly late tonight and early Monday morning, with drier air aloft building in to cut off precip by the afternoon. QPF amounts look light with this system, around a tenth of an inch, which is good because temps in the SW VA and East TN mountains Monday morning will be near freezing.
This will keep temperatures in this portion of the CWA cooler than the rest. The frontal boundary will not cause too much of a change in temperatures as highs Monday will be in the 70s to near 80 degrees with the higher values across the Rio Grande Valley.
The northern edge of the low clouds was located along the I-59 corridor at 3 AM CDT this morning. Temperatures have been held up by the cloud cover and freezing temperatures not likely to occur south of I-20 before sunrise. A nicer warm-up today with most areas climbing into the lower to middle 60s. A rapid change in the weather tonight as a fast moving short wave trof passes to the north of Alabama.
Weak high pressure will lose its grip on the area today, as s/wv mid level energy approaches from the NW.
Very cold westerly flow under an advancing short wave trough axis is causing a mix of weather forcing. Have placed the highest POPS of around 40 pct across the northwest mountains, with a diminishing chance of measurable precip southeast (downwind) of the mountains. Model 800mb temps support max temps no better than the low 30s in the northwest, to the low and mid 40s across the southeast counties.
Forecast snow amounts have not changed much with this forecast package with the higher amounts continuing to stretch over western and southern North Dakota. Some concern for a little light freezing drizzle remains over the far southwest, though any accumulation will be minimal.
Overnight, expect additional snow, with the surface cyclone moving into southern Iowa, and a secondary short wave trough glancing the south. After midnight, cannot rule out some light freezing drizzle in the far south as ice introduction aloft becomes questionable. Monday 500mb trough axis and core of 700-500mb omega will be shifting east of the area Monday morning, but there should be enough low-level convergence for light snow to last through the mid morning hours. For impacts, expect areas of slippery travel through 8-9 AM and then a quick improvement as temperatures rise above freezing. Highs will be in the lower 40s on average.
340 AM CDT Sun Apr 8 2018 A chance for snow across parts of central Minnesota today into Monday but otherwise just increasing clouds and just a bit warmer today across the Northland with highs in the mid 30s. Decreasing clouds and warmer on Monday with highs in the upper 30s, which is still around ten degrees below normal for this time of year. A broad area of high pressure builds across the northern Great Plains on Monday leading to clearing skies, though with a lack of a significant airmass change diurnal heating is expected to lead to afternoon cu across much of the Northland on Monday afternoon.
Freezing level tonight was at 14,100 feet, with the -20C level at 22,500 feet. /issued 318 PM CDT Sat Mar 24 2018/ Generally tranquil conditions will prevail through the early part of the new week as ridging aloft builds into the central Gulf Coast region and eventually across much of the eastern conus. In the near term, a short wave trough moving across the Ohio Valley and into the mid Atlantic region will push a cold front south toward the forecast area later tonight and Sunday.
/issued 236 PM CDT Sat Mar 24 2018/ Tonight, the Pacific trough to our west will continue to dig southeastward through the West Coast. PWs will be near an inch, and upslope flow along the surface cold front could be just strong enough to produce light showers across parts of the FA area with an isolated thunderstorm developing in the far SE portions of the Rolling Plains.
On Sunday, an approaching open wave trough will continue to slide southeastward. The winners will likely be the eastern Uintah mountains where a couple of inches of snow are possible at the higher elevations.
As the 500 hPa closed low currently over central IA weakens and moves into IL this evening, expect the snow band to dissipate and drop south of the forecast area. Clouds will clear from north to south overnight with mostly sunny skies on Sunday as 500 hPa ridging moves across the region.
Temperatures are in the lower 70s. In the low levels of the atmosphere, an Atlantic ridge of high pressure will extend across Central Florida overnight. In the mid levels of the atmosphere, an area of high pressure will be centered over the western Gulf of Mexico tonight. In the upper levels of the atmosphere, a trough of low pressure will be located over the Bahamas overnight.
815 PM EDT Sat Mar 24 2018 Forecast is on track as the sea breeze pushes inland resulting in cooler temperatures near the coast.
Drier weather is then in store for the remainder of the short term period as weak ridging builds in aloft.
Surface temps will be supportive of rain and/or freezing rain. Plan for slick roads due to rain freezing on impact with road/bridge/sidewalk surfaces. P-type could come down to surface temps, which should hover within a few degrees of freezing. Precipitation type will be a mix of freezing rain and sleet, along with an outside possibility for rain in the southern part of the CWA and snow along the ND/SD border.
634 PM CDT Sat Mar 24 2018 The primary forecast challenge through Sunday deals stratus coverage and (freezing?) drizzle chances due to persistent upslope flow and good surface moisture. Isentropic analysis and forecast soundings show abundant dry air in the mid and upper levels, indicating all the moisture to be trapped in the lowest 100mb or so. Temperatures will be critical as forecast lows hover right around the freezing mark. Higher confidence of freezing drizzle exists over north central Neb where lows may dip into the 20s. Normals for the season around 30 for lows and low 50s for the highs.
630 PM CDT Sat Mar 24 2018 Weak low pressure was located over NE Arkansas with a cold front trailing to the southwest of the low. High pressure was located over the central Gulf and the pressure gradient remained fairly tight. Our best rain chances remain in place for the Tues/Thurs timeframe with the approach of the very well defined upper trof/low from the west and its associated cold front. However, that being said, the progged track of this upper low is indicating that some strong dynamics could be in play when all is done.
Limited mid-level moisture and generally weak lift should lead to primarily freezing drizzle or drizzle late tonight into Sunday. Expecting temperatures in our west to only dip to a degree or two below freezing tonight in these areas, and with daytime road surface temperatures warming well above freezing, impacts may also be confined to elevated/untreated surfaces, even during the early morning.
Widespread cloud cover across the area is also hindering any potential for diabatic heating, so will likely see temperatures max out this afternoon in the upper 40s to lower 50s, which in some cases, especially south of I-70 much cooler than the max temperatures experienced earlier this morning before the boundary came through.
800 PM EDT Sat Mar 24 2018 A back door front will move through the region late tonight bringing rain, with wedge conditions and associated low cloudiness and cooler temps developing over our forecast area and lingering through Sunday.
A near repeat tomorrow with temperatures ranging from the low to mid 80s east to the low to mid 90s west.
The upper low center is currently centered over Iowa this afternoon. While clouds may attempt to break towards the Emporia area by late afternoon, the stratus is expected to fill back in overnight as the system exits eastward and ridging amplifies across the central plains. Sfc dewpoints in the 50s, possibly 60, advects northward towards the CWA, while a stout 850 mb jet overruns a warm front bisecting the CWA west to east.
At 1030 PM, a line of showers with isolated thunder is moving south along a cold front near the Tennessee and Mississippi state line. Temperatures will begin to drop behind the front as cooler and drier air works its way in overnight. Expect temperatures to drop into the lower 40s across the north, with lower 50s across the south.
A short break is in store for the area in the late afternoon before a weaker round of precip drops southward in behind the low as it shifts to the east. Moving into the extended, a quiet end to the weekend as sunny skies return, albeit with a cooler airmass and temps only climbing into the upper 30s/lower 40s. The weak ridging aloft shifts to the east and the flow into the region becomes more southwesterly aloft.
703 PM CDT Sat Mar 24 2018 Issued 355 PM CDT Sat Mar 24 2018 Main forecast concern is timing of next short wave trough approaching the area later Sunday afternoon. Water vapor imagery showing cirrostratus associated with outgoing trough is finally thinning over the western CWA. We kept the low end chance PoP for some light rain moving into the far west after 21z Sunday.
A weak upper trough will bring a few showers tonight.
714 PM CDT Sat Mar 24 2018 A cold front is moving through the eastern Ozarks and south central Missouri this afternoon. Temperatures will be much cooler tonight into the lower and middle 30s with afternoon highs Sunday in the middle to upper 50s. A large and deep upper level trough will slowly move across the western U.
Breezy West southwest winds are forecast to develop behind the trough later tonight and into Sunday afternoon before beginning to decrease. Snow melt to continued aid in the redevelopment of low cloud and areas of fog and freezing fog tonight mainly over the northern zones. Previous Discussion: Upper trof moves through the region over the next few days for continued mild temperatures. Some energy in the base of the trof could bring some precipitation to southern Montana on Sunday night. Flow turns northwest behind the trof, for unsettled but cooler weather. Synopsis: A weak disturbance and trough is forecast to move across NE MT overnight tonight. Winds:Ahead of the trough winds are forecast from the WSW then shifting to the WNW overnight 5-15kts with gust from 15-25kts.
Scattered showers will be possible south of San Jose this afternoon as a cold front moves through.