Aikyam-Lab/Synoptic-Bench huggingface dataset:
/NEW/ /Through Wednesday/ The cold front has cleared the entire CWA to the south, and slightly cooler but significantly drier air filtering into North Texas within breezy northerly flow. These will be some of the lowest temperatures observed since early May. /Issued 253 PM CDT Tue Sep 21 2021/ /Wednesday night through Tuesday/ A building ridge aloft and the gradual return of Gulf moisture will result in warmer weather late in the week.
Overnight, winds will become light and variable with temperatures staying in the low to mid 70s. High pressure will continue to dominate across the waters through midweek, before a weak cold front approaches the area and stalls across the northern waters late in the week.
A sprawling area of high pressure was located over the Central Rockies into the Plains and Midwest. This system has brought a much cooler and drier air mass into eastern Iowa and northwest Illinois. Quiet weather is expected tonight with lows in the low 50s across the east/southeast outlook area to mid 40s in the west. An area of low pressure is forecast to track through the Ohio Valley on Wednesday, which will increase the pressure gradient locally leading to another breezy day.
555 PM MDT Tue Sep 21 2021 Building ridge will bring clear/dry weather tonight. Lee side surface trof should yield modestly gusty winds along the foothills, and have made some minor wind/temp adjustments in these areas. Wednesday will be warmer with highs into the low 80s many locations. Upper ridging dominated the weather pattern through Wednesday night, increasing temperatures to the low 80s on Wednesday and some winds 10-15 mph mixing down across the area, with locally higher amounts possible along the foothills west of Billings.
914 PM PDT Tue Sep 21 2021 A cold front on Wednesday is expected to bring increasing clouds and breezy winds across portions of central and eastern Washington.
457 AM EDT Wed Sep 22 2021 A line of thunderstorms is likely this afternoon with the passage of a cold front. Showers will continue throughout the early morning, primarily east of Pittsburgh, as deep moisture convergence resides over the ridges. Warm, moist air ahead of a cold front will keep temperatures above the climatological average. A trough near the Midwest will continue to deepen and dig eastward later today. A surface cold front, ahead of the occluding system will also cross this afternoon and exit into central PA by late evening.
Surface analysis shows a cold front across Middle TN with convection developing along and ahead of this boundary. Much drier and cooler air will advect across the area in the wake of this front as high pressure builds in from the northwest. Showers will be moving in from the west over the next few hours as a cold front approaches. DGS Chattanooga Airport, TN 71 52 71 50 74 / 70 0 0 0 0 Knoxville McGhee Tyson Airport, TN 72 50 70 48 74 / 80 10 0 0 0 Oak Ridge, TN 69 49 69 47 73 / 80 10 0 0 0 Tri Cities Airport, TN 74 49 67 42 73 / 80 30 10 0 0.
/issued 838 PM CDT Tue Sep 21 2021/ The cold front has officially reached the greater Memphis area. /issued 332 PM CDT Tue Sep 21 2021/ The early season cold front has finally arrived, and looks to be located just to the east of the Mississippi river, located along a line generally from Covington, TN to Memphis, to Tunica, MS. A prefrontal trough may result in a wind shift before the front. Behind the front a cooler and drier Fall-like airmass will move into the Midsouth.
Approaching steadily from the west is our much-anticipated cold front. Temperatures 10-15 degrees F below normal continue in this cooler air mass with calm winds and clear skies.
In upper levels, overall mean ridge in the western CONUS and trough in the eastern CONUS will ensure a generally northwest flow aloft. At the surface, the ridge helping to dampen the winds and allow for near maximum radiational cooling this morning will shift, and allow perhaps some gusts from the south near 15 mph in our western CWA today, considering expected surface pressure gradients.
302 AM CDT Wed Sep 22 2021 Upper level high pressure ridge center from central Arizona into southwest New Mexico will shift into far west Texas and southern New Mexico tonight. Today will remain near or slightly cooler than normal.
Primary surge of warm advection starts to work into area from south to north later Friday as the 850 low and warm front reach far southern Wisconsin.
A mix of rain, snow, and freezing rain in the Lower Treasure Valley (west of Boise metro) are expected to change to rain this afternoon. These highlights will weaken through the overnight hours as a warm front progresses through the forecast area. Areas of freezing rain will be possible over these lingering areas as the conversion to rainfall occurs. Cooler temperatures anticipated across the area as the axis of this approaching trough crosses the forecast area by late Friday afternoon.
Skies are mostly clear with cumulus mainly over the lower and middle Keys and over the Florida Straits. Temperatures have leveled off near 80 with dewpoints in the low 70s. On Friday and Friday night winds will continue to veer towards easterly as high pressure moves over the eastern seaboard then off the coast.
Arctic high pressure was centered over northwest Missouri this morning, forcing cold air across the entire state of Missouri. As southerly winds return later today in response to high pressure shifting east, temperatures won't cool as much tonight with some areas remaining in the low 30s. There is some question regarding drizzle or freezing drizzle chances for southeast Kansas and western Missouri for Friday morning. We elected to keep drizzle and freezing drizzle out of the forecast due to dry air at the surface. We could experience a 10 degree dew point spread at the surface through Friday morning as southeast trajectories blow dry air off of the departing Arctic airmass across the lower Mississippi River Valley.
308 PM EST Thu Dec 15 2016 Cold high pressure will settle over the region tonight and Friday bringing well below normal temperatures. Moisture will increase Friday night into the weekend as a warm front develops and lifts northward bringing increased chances of precipitation.
Freezing temperatures in the valley this weekend with dry conditions. Upper troughing will allow for continued shower threat over the Sierra Cascade range on Friday but elsewhere should remain dry Friday with daytime temperatures on the cool side in cold air behind the front. Weather clears out Friday night as upper ridging develops over the eastern Pacific and northerly winds develop. Clear skies and cold airmass will allow overnight lows throughout the central valley to drop to near or below freezing.
Forecast soundings show a deepening saturated layer that may eventually become sufficient for drizzle, although surface observations and the 12z OUN sounding show a pronounced dry layer in the low levels that would need to be overcome. Current thinking is that temperatures should rise to above freezing before sufficient moisture deepening and saturation of low levels results in drizzle. Freezing drizzle seems unlikely but we will continue to monitor trends and make adjustments if the timing becomes more supportive of a brief period of freezing drizzle very late this afternoon or into the evening. A nearly zonal flow across the lower 48 early Friday will amplify as a trough approaches and moves across the western states. Meanwhile, strong southerly winds will prevail across the southern Plains as low pressure deepens across Colorado.
/issued 351 AM CST Thu Dec 15 2016/ Arctic high pressure continues to build into the Mid-South this morning. The high will provide the area with another chilly day. The combination of cold air advection and some mid to high clouds streaming over the area will keep temperatures from getting above freezing across much of Northeast Arkansas, the Missouri Bootheel, and West Tennessee. The high will shift east by Friday morning. Highs will be around 20 degrees warmer than today with readings ranging from the mid 40s to upper 50s. Chances for warm air advection showers will occur by Friday afternoon ahead of a developing low pressure system over the Central Plains.
Latest surface analysis depicts strong arctic high pressure centered over northern Missouri, with resulting northerly surface flow over the local region. 21z H5 analysis depicts a longwave trough axis extending from eastern Canada southward along the Atlantic seaboard, with a ridge axis over the western half of CONUS. This will allow temperatures on Friday to be nearly 20 degrees warmer than Thursday highs.
236 PM CST Thu Dec 15 2016 There is a weak upper ridge over the western half of the country with northwest flow over West Texas and southeast New Mexico. Temperatures today are expected to be cooler than yesterday with highs ranging from the 40s across the Western Low Rolling Plains to the 70s across the Presidio Valley and Van Horn area. The eastern portion of the CWA is expected to remain cloudy today so will be cooler than the rest of the area. There is a chance of patchy drizzle and fog across the Lower Trans Pecos and Permian Basin tonight and Friday morning.
A flat 500-hPa ridge will prevail across the Central Rockies and extending out across Kansas. To the northeast, the cooler 850-hPa airmass will only slightly moderate. The net result for sfc temperatures is a fairly cool day ranging from around freezing in the northeast to around 50F to the southwest. There is only a slight chance of freezing drizzle across Barber county through tomorrow morning. Strong 250-hPa westerly flow is expected with resultant low level cyclogenesis across the High Plains. A warm front will spread northward.
/issued 326 AM CST Thu Dec 15 2016/ (Today and Tonight) Stratus is steadily spreading across West Central Texas early this morning, with temperatures ranging from the mid 20s to near 30 across the Big Country to the low to mid 40s across the Interstate 10 corridor. Highs will range from the mid 40s across the Big Country, to the low to mid 50s across most of the rest of the forecast area.
Only weak isentropic lift within this low stratus prior to 12Z Friday will be limit the production of droplets large enough to fall as precipitation. Any precipitation that does manage to reach the ground will likely be freezing drizzle given the shallow moisture column and below-freezing surface wet bulb values. 00", but given the high impacts of any freezing precip, opted to err on the side of caution with respect to precip start time. Warm advection and isentropic lift will increase Friday morning as low pressure develops in the lee of the Rockies. Models show warm nose aloft by early Friday morning with light precipitation developing as lower layers saturate and upward vertical motion increases in the low layers as the morning wears on. Currently will go with a lean toward surface temps warming above freezing by midday.
With the push of warmer air, thicknesses increase, so snow ratios will be decreasing during this time.
Chattanooga Airport, TN 36 21 45 37 / 0 0 10 60 Knoxville McGhee Tyson Airport, TN 33 16 44 35 / 0 0 10 50 Oak Ridge, TN 34 17 42 35 / 0 0 10 50 Tri Cities Airport, TN 27 12 38 29 / 0 0 10 30.
1157 AM EST Thu Dec 15 2016 High pressure centered to the west will circulate very cold air across the region today and tonight.
1214 PM EST Thu Dec 15 2016 Cold front bringing very cold weather today and Friday.
This is primarily recirculated continental polar air from yesterday's cold front, so temperature recovery today will not be that significant. As dewpoints climb to meet these temperatures, the boundary layer will near saturation, particularly across the eastern zones, where patchy freezing fog was included in the grids overnight. Along with WFO Goodland, do not feel the stratus and moisture will be deep enough to support freezing drizzle, but this will have to monitored carefully by the next couple of shifts. A strong temperature gradient is expected across SW KS, and a strong surface cyclone will travel along this gradient, from near Denver at 6 am, to SE Colorado at midday, to near/south of Dodge City by 6 pm.
With weak surface coastal troughing and overrunning, coverage should continue into the evening hours across mainly the Lower Rio Grande Valley as 850mb winds out of the south increase tonight atop northerly winds at the surface.
1231 PM CST Thu Dec 15 2016 Apparent temperatures have increased and are now mostly warmer than advisory criteria. Visible satellite indicated some thin cirrus spilling over the upper ridge and moving across the southern zones. Split flow consolidates by Fri ahead of another trough over northwestern Canada. Water vapor loop indicated an upper trough over northern ALTA and northern SASK and another trough off the BC coast. The upper troughs will sweep across the Northern and Central Plains on Sat. A broad upper ridge centered over the US Rockies will shift east tonight.
247 PM EST Thu Dec 15 2016 Snow showers will diminish across the I-80 corridor as the evening progresses with building high pressure. Warm advection is projected to intensify late Friday ahead of a digging trough over the Upper Midwest, which will cause snow chances to increase as the warm front extends across the Upper Ohio Valley.
Kept temperatures in north central Oklahoma a bit cooler to account for lingering cloud cover.
Latest satellite imagery shows upper level trough off the western U. ahead of the trough. Over the northern plains widespread pressure falls continue as low pressure develops over the northern and central Rockies. At this time the northern counties of Lamoure and Logan would be on the low end of advisory threshold.
Sly flow has returned across much of TX/OK to our w, and will spread ewd into our region this evening and overnight, as low pressure deepens across the Southern Plains. Temperatures will top out some 15-20 degrees warmer for Friday, as strong WAA continues ahead of an approaching upper disturbance.
This afternoons surface analysis indicated a weak cold front draped east to west across the southern tip of Florida. As a drier and cooler airmass advects into the region, low temperatures will drop to around 70 degrees along the east coast metro and down to the upper 50s further west in Glades, Hendry and Collier counties.
202 PM EST Thu Dec 15 2016 Cold high pressure will build over the area tonight and Friday.
102 PM EST Thu Dec 15 2016 High pressure centered to the west will circulate very cold air across the region today and tonight.
This activity will lift east of the CWA through the evening hours as a broad ridge over the Central Rockies weakens in advance of the next storm system. Given that moisture content will be limited to 850 hPa and below, any precip that does form will be in the form of freezing drizzle early Friday morning. A residual layer of dry air in the lower levels may mitigate some of the potential for ice accumulation, though generally thinking that there is at least some potential for icy surfaces to form over areas west of the I-35 corridor. By the afternoon, increasing surface temperatures will maintain liquid precip for areas south of Highway 36, and freezing drizzle for northern Missouri.
With the WAA and 700 mb temps around 0C, sfc temps in the Arlington area are currently in the mid-to-upper 30s and in the low 30s over the Summit. Arctic cold front will slide southward to the east of the Laramie Range through sunrise on Friday.
1043 AM MST Thu Dec 15 2016 Made minor adjustments to Friday forecast based on high range guidance and latest 12Z guidance to remove freezing drizzle mention, add patchy freezing fog (in the morning), and increase sky cover. Based on shallow saturated layer (and supported by a consensus of hi res members) freezing fog appears more likely Fri morning in our east, with stratus during the day. Only the higher terrain areas of eastern Colorado will see a slight warmup where temperatures may reach the 40s, but expecting 30s for highs elsewhere. Forecast point soundings indicate it might be deep enough for a little light freezing drizzle to develop.
A warm front will push northward through the region tomorrow, and highs will be around 10 to 15 degrees warmer than today. Tomorrow night will also be warmer, and again patchy fog to areas of fog can be expected across most of the region.
Snow levels will initially range from 7500-8500 feet, but will fall rapidly to around 5000 feet Friday evening and Friday night as a cold front moves through the area. In addition, for elevations above 9000 feet freezing drizzle and riming will be a possibility. A high pressure ridge, peaking in amplitude over Arizona this morning, will begin to break down this afternoon as a cold low pressure trough moves southward along the west coast on the United States. This will be short-lived as strong southwest flow and warm advection develop ahead of the cold front. Wind speeds will likley reach peak gusts near any shower activity, and again on Friday evening as the cold front moves through. Expect deteriorating conditions with showers spreading west to east aft 06Z as a low pressure system moves into the state.
Snow levels will initially range from 7000-8500 feet, but will fall rapidly to around 5000 feet Friday night as a cold front moves across Arizona. In addition, for elevations above 9000 feet freezing drizzle and riming will be a possibility. A trough of low pressure was centered just off the coast of Washington and Oregon during the afternoon hours, starting to dive to the southeast. The trough continues to head southeastward toward Arizona.
/issued 910 AM EST Thu Dec 15 2016/ A weakening cold front across the central peninsula from near a Melbourne to Sarasota line early this morning will continue to sag southward through the southern forecast area through the afternoon. Temperatures today will be slightly cooler than previous days (though still running above normal) especially across northern and central zones where temperatures should max out around 70 to the lower 70s across the Nature Coast, mid 70s central zones, and upper 70s far south with a slow decrease in humidity values expected which will make for more comfortable outdoor conditions during the afternoon.
An upper level trough continues to push eastward across the eastern CONUS with its axis now to our east, resulting in northwesterly flow aloft. This is currently mirrored at the surface across our area, with dry northwesterly/northerly flow prevailing as a cold front has moved offshore and now stretches across the northeastern Gulf.
The high wind speeds near Bordeaux are a result of stronger winds around 750mb upstream blowing through the gap just west of Bordeaux. High should stay in place for next 24 hours or so with upper ridge axis passing overhead tonight into Wednesday morning.
357 PM EST Tue Jan 17 2017 A weak area of low pressure will move northeast up the Saint Lawrence valley overnight. A secondary low pressure area will form south of Long Island late tonight and will move slowly eastward south of New England on Wednesday. A mix of snow, sleet, freezing rain and rain will be over the north country overnight through Wednesday.
Cold front will be crossing the forecast area this evening and pushing east of the area tonight. Despite a cold front moving through, the air behind it isn't too much cooler and highs tomorrow will still be in the 50s. An active weather pattern continues through this period as a trio of closed cyclonic circulations move across the lower 48.
202 PM MST Tue Jan 17 2017 Latest upper analysis shows the region under the influence of a an upper ridge. The surface analysis depicts a weakly defined N-S oriented trough across the central Dakotas/Nebraska. 850mb temperatures will generally be around 3C warmer than today.
As warm advection continues to intensify tonight and even better low level moisture is forced up and over the cold front to the south, ceilings will continue to drop and IFR conditions are likely overnight. /issued 410 AM CST Tue Jan 17 2017/ (Today and Tonight) A weak cold front moved across the area overnight and will remain well south of the area the next 24 hours. A closed upper low currently over northern Mexico will lift northeast into New Mexico by early Wednesday.
1203 PM EST Tue Jan 17 2017 Weak high pressure will move across the Coastal Plain today, moving over the western Atlantic tonight.
Mountains will be dry and warm into the low 30s. Low and mid-level clouds remain over the southeast corner of the CWA at this hour, aligned with a southwest-northeast tilted upper trough axis over the area. Otherwise a dry and warmer day with light winds. Lows tonight about 5 deg f warmer with the warmest readings along the base of the foothills. Benign weather pattern for the next 60 hours with dry conditions and warmer temperatures for much of the region.
233 PM EST Tue Jan 17 2017 While a cold front crossing the region will bring temperatures closer to normal on Wednesday, the entire 7 day forecast period will have above normal temperatures.
night periods as high pressure ridging transitions to SW flow. Biggest challenge for the forecast will be the high temperatures.
With westerly low level flow, albeit weak, and a sharp inversion with temperatures around freezing at 1. Ridge tops, like the Prairie Coteau and Leola Hills, should warm into the upper 20s or warmer today. Warmer air will filter into the region on Wednesday with temperatures reaching the low to mid 30s for most locations. Have ignored the warmer GFS solution and kept temperatures cool.
950 AM MST Tue Jan 17 2017 09z surface analysis had low over KPIA with weak high over the CWA and lee trough from central MT into central CO. Some CI spilling over ridge into the CWA. Today through Wednesday, upper level ridge will build into the northern plains with a downslope component to low level flow as well as sustained warm air advection. This will push lee trough east as a warm front. Battle between snow cover and warmer air will continue with wide range in local temperature anomalies expected.
IFR conditions are possible Wednesday morning, with KMLC seeing the highest chance of IFR conditions.
317 PM CST Tue Jan 17 2017 Rain has moved off to the east with the cold front, which is slowly working its way out of the area. Models want to keep rain chances mainly along the Plateau this evening and even into the early overnight hours as the cold front tries to hang on with the upper low.
High temperatures had topped out in the low 80s along the east coast with mid-80s inland, values around 5 degrees above normal for this time of year.
Local and regional radars still showing some returns along this trough of low pressure. Observations suggest this is mainly drizzle/freezing drizzle but some rain with the higher returns along with a bit of sleet and snow. The short range meso scale models all suggest this precipitation will move slowly southeast through the afternoon, in association with the secondary upper level low moving across, and may not exit the area until early this evening.
Mid level ridging will help relax the wind fields tonight leading to a reduction in the convective activity. With the loss of mid level support the frontal boundary will only ooze a little further south tonight before stalling and then begin to back up as a warm front Wednesday. Cold core moving into the Plains will once again induce a mid level southwest flow regime with an increase in isentropic ascent, especially near the retreating warm front.
Temperatures are remaining in the low 40s under it so adjusted temps down a few degrees there near Ada and Atoka.
A weak, slow moving cold front was located just to the west. Temperatures will remain mild, with most locations reaching the low to mid 60s. A cold front will push across the region today.
1129 AM CST Tue Jan 17 2017 A cold front across the region will maintain VCSH conditions through much of the terminal forecast period.