Aikyam-Lab/Synoptic-Bench huggingface dataset:
A northwest flow aloft will develop across the Western High Plains tonight as ridging across the Great Basin continues to build. Lee side troughing will develop Monday helping to bring more of a southeasterly flow about to western Kansas with H85 temperatures ranging from the mid 20s(C) in central Kansas to the upper 20s(C) closer to the Colorado border. Precip chances will be limited, but not completely ruled out across western Kansas early this week as weak upper level ridging shifts slowly eastward across the South Plains. Meanwhile, steep low/mid level lapse rates and increased convergence in the vicinity of a lee side trough across eastern Colorado is expected to provide a trigger for thunderstorms late in the day with storms then potentially drifting into extreme western Kansas later in the evening.
Most importantly, light onshore steering winds about the northern periphery of an area of high pressure have driven showers and storms onshore each day. This combined with rich tropical moisture and the presence of a couple of weak upper tropospheric low pressure systems has sparked abundant shower and thunderstorm activity, which regenerates over the warm waters of the Gulf of Mexico. High pressure remains situated across south Florida.
Atlc ridge axis draped across Lake Okeechobee region will continue to produce a South to southwest flow 10 knots or less, except slightly above 10 knots in the offshore northern waters.
Cloud cover increases early Monday morning, but there will be a noticeable air mass change with a cooler and less humid start to the work week. JEE 1248 PM CDT Compact and digging upper trough over the upper great lakes will continue southeast tonight. Height falls on the back side of the trough will provide enough forcing ahead of a cold frontal boundary to trigger scattered showers and thunderstorms during the peak heating period this afternoon/early evening. The thunderstorm concerns will end quickly this evening as these combined factors all shift southeast with the arrival of the cooler and drier airmass behind the frontal boundary and increased surface pressure ahead of large high pressure across the upper midwest.
/issued 403 PM CDT Sun Jul 23 2017/ Despite more cloud cover and scattered convection today, daytime temperatures were still able to soar well into the low to mid 90s over much of the region with borderline heat advisory criteria in most locations. The good news is we should not need additional advisories for at least the next couple days with the breakdown of the upper level ridge due to the westward advancing upper disturbance/remnant Gulf easterly wave. Rain chances will begin to significantly fall off heading into mid week as the upper level ridge becomes firmly implanted back over the region.
736 PM EDT Sun Jul 23 2017 A stagnant mid-level trough will keep very humid conditions over the region through Monday with a continued threat for showers and thunderstorms.
1027 PM CDT Sun Jul 23 2017 High pressure at the surface will move off to the east tonight, shifting the forecast area's winds around to an east to southeast direction. Used bias corrected guidance values for tonight's lows which captured the warmer readings in the 60s in our eastern zones due to the return flow. Conversely, cooler readings in the 50s are warranted along and east of the I 29 corridor with lighter winds. Monday will be a warmer day, and fairly breezy along and west of the James River valley as a southeast flow of air increases. Manually raised guidance temperatures east of I 29 into the lower 80s as 850mb temperatures do not justify mid to upper 70s at this time.
Regarding the heat advisory currently out, heat indexes within the advisory at this hour are generally in the low to mid 90s.
837 PM EDT Sun Jul 23 2017 A ridge of high pressure will gradually shift offshore into the maritimes tonight into Monday. Low pressure will approach from the southwest later tonight and Monday and will deliver cooler temperatures and the likelihood of rain in an onshore flow.
A tighter surface pressure gradient across much of the forecast area will shift to the southeast as high pressure moves into Wisconsin so winds should further diminish. Skies are expected to clear with the arrival of the high and an upstream mid level ridge. North central and central Wisconsin appear to have the highest potential for fog issues later tonight.
Dry weather is then expected overnight and on Monday as high pressure builds into the region. Might be some fog tonight in the west toward the high building in. Dry weather is then expected overnight and on Monday as high pressure builds into the region. The lack of sunshine along with cooler temps aloft will result in below normal high temps in the low to mid 70s.
Light northerly winds will go light and variable tonight, before shifting to the south for Monday morning as high pressure moves off to the east.
As of 19z, a weak cold front was positioned from central OK into northeastern AR. Upper level ridging continues to organized across the Rockies. Td's in the eastern half of the CWA remain in the low to middle 70s, resulting in heat index values approaching 100. WAA will return Monday morning across the western half of the area, as the high pressure shunts eastward, allowing southeasterly winds to return.
With loss of heating and weak wind fields in the lowest 3 km, this convection should weaken as it nears I-20. The focus for convection this evening into the overnight hours will be along a very weak cold front currently moving across Central Oklahoma. Monday should be slightly cooler than today due to increasing cloudiness and slightly higher storm coverage.
Thunderstorm activity across central Indiana will come to an end tonight as a cold front exits the area and cooler drier air filters in.
A relatively tranquil afternoon for late July continues across South Florida, as deep subtropical ridging continues to build across the region. In addition to the ridging in place, a remnant SAL layer continues to move across the southern half of the area, with a noted warming and drying trend in the midlevels on the 12z observed KMFL sounding. An occasional isolated shower/storm may affect the far southern tip of the peninsula towards the Keys as well along the southern periphery of the subtropical ridge axis. The remnant SAL layer will continue to drift off into the Gulf of Mexico Monday as deep subtropical ridging remains locked in place across the region.
934 PM EDT Sun Jul 23 2017 Upper level ridging will weaken across the area today as the upper level trough digs over the eastern US.
510 PM MDT Sun Jul 23 2017 Latest upper air data shows the ridge over the Central Rockies. At the surface a high pressure was moving east out of the Tri-State Area. Monday will continue to be dry as the ridge builds over the Central Plains and an upper level short wave trough tracks over the Northern Plains. Highs will be warmer than today by a few degrees.
613 PM CDT Sun Jul 23 2017 1248 PM CDT Compact and digging upper trough over the upper great lakes will continue southeast tonight. Height falls on the back side of the trough will provide enough forcing ahead of a cold frontal boundary to trigger scattered showers and thunderstorms during the peak heating period this afternoon/early evening. The thunderstorm concerns will end quickly this evening as these combined factors all shift southeast with the arrival of the cooler and drier airmass behind the frontal boundary and increased surface pressure ahead of large high pressure across the upper midwest.
631 PM CDT Sun Jul 23 2017 Isolated to scattered thunderstorms have developed near a cold front which is slowly sinking southward through Missouri and Illinois. Highs tomorrow will be 5-10 degrees cooler across the area except over the eastern Ozarks where temperatures will likely be similar to what they were today. Light ely flow and a mostly clear sky shud allow for ample radiational cooling and have trended aob the cooler guidance. With sfc winds becoming more sly on Tues and the upper ridge building into the area, temps shud warm up quickly. Much cooler conditions currently expected with 850mb temps in the 12C to 14C range.
In the low to mid levels of the atmosphere, an Atlantic ridge of high pressure will extend across south central Florida overnight. In the upper levels of the atmosphere, an area of low pressure will be located over the central Gulf of Mexico tonight.
19Z analysis shows a cold front from northeast WI into central IA with light northwest wind and dewpoints in the upper 50s to lower 60s behind the boundary. This much more comfortable air mass will settle across the forecast area tonight as high pressure moves across northern MN/WI. For Monday, high pressure moves slowly into the western Great Lakes region resulting in partly to mostly sunny skies, light easterly winds, and temperatures in the mid to upper 70s.
Fcst soundings also showing little in the way of saturation on Monday and warmer convective temps so will not mention precip in any of the TAFs on Monday. With the upper low near the TX/LA border continuing to weaken tonight, the ridge aloft out west will begin to build into the area tomorrow.
The RAP, HRRR and HRRR exp suggest an isolated thunderstorm may affect Pine Ridge. Strong heating and a dryline bulge across Pine Ridge Monday afternoon could spark isolated thunderstorms as suggested by the NAM.
though area of cloudiness in the San Luis Valley and Southwest mountains appear to be related to an upper level shear axis around southern side of the upper high. Monday looks similar to today, though a few degrees warmer.
Temperatures and heat indices for the most part are cooler this afternoon than they were earlier this weekend, but given isolated to scattered nature of on-going showers, will keep the advisory going. Hot and humid conditions continued across the greater Tennessee Valley region, as broad upper level ridging to our north and west slowly breaks down. Warm air aloft associated with the upper ridge for the most part has kept convection overall tamped down. Despite more clouds and showers, low temperatures will only cool in the low/mid 70s with light winds. With more clouds than sun, temperatures to start a new work week will be a bit cooler, "only" in the upper 80s to around 90. Even with dewpoints in the lower 70s, they should not be high enough to warrant Heat Advisories - at least this issuance.
As high pressure builds up from the Great Basin, temperatures will warm and moisture will move into the area supporting increased showers and isolated thunderstorms on Monday.
601 PM CDT Sun Jul 23 2017 High pressure at the surface will move off to the east tonight, shifting the forecast area's winds around to an east to southeast direction. Used bias corrected guidance values for tonight's lows which captured the warmer readings in the 60s in our eastern zones due to the return flow. Conversely, cooler readings in the 50s are warranted along and east of the I 29 corridor with lighter winds. Monday will be a warmer day, and fairly breezy along and west of the James River valley as a southeast flow of air increases. Manually raised guidance temperatures east of I 29 into the lower 80s as 850mb temperatures do not justify mid to upper 70s at this time.
However abundant cloud cover also remains from yesterday keeping temps much cooler than forecast, partially countering the effects of the MCV and preventing a more widespread outbreak of rainfall this afternoon. There should be fewer clouds tomorrow allowing for greater heating, and combined with a weak upper low slowly migrating north from the Big Bend will again provide rain chances for one more day.
514 PM MDT Sun Jul 23 2017 Latest upper analysis shows a ridge over much of the western CONUS with and upper trough digging southward into the Pacific Northwest. On Monday, the upper ridge will build eastward over the high plains with the thermal ridge peaking over the forecast area ahead of an upper low and associated trough crossing the Canadian prairie provinces.
First is the upper trough axis located approximately along I-57 and pushing eastward. Winds will diminish and turn northerly overnight behind the trough axis with drier air moving in, allowing temperatures to fall into the 60s for lows.
933 PM EDT Sun Jul 23 2017 A stagnant mid-level trough will keep very humid conditions over the region through Monday with a continued threat for showers and thunderstorms.
1056 PM EDT Sun Jul 23 2017 A ridge of high pressure will gradually shift offshore into the maritimes tonight into Monday. Low pressure will approach from the southwest later tonight and Monday and will deliver cooler temperatures and the likelihood of rain in an onshore flow.
This convection is being aided by some weak upper level support due to a mid to upper level low in southeast Texas. Isolated shower activity could linger into the night time hours due to the aforementioned upper low still in the area. High pressure will continue to dominate the region and keep high temperatures in the triple digits for many locations across South Central Texas.
518 PM MDT Sun Jul 23 2017 Pretty quiet and hot weather pattern will be in place through Monday with strong ridging aloft and limited monsoonal moisture. The pattern will be similar for Monday with ridging/subsidence aloft keeping tstm chances rather limited. Not expecting much convective initiation along the trough except in areas near the southern Laramie Range.
810 PM MDT Sun Jul 23 2017 Only some isolated convection left over the higher terrain with nothing across the plains. There is a nearly stationary flow this afternoon and evening with the upper ridge centered over the Great Basin and central Rockies. On Monday the upper ridge will be centered over New Mexico and west Texas, with weak west to southwesterly flow aloft over the cwa.
Think the winds will stay up enough at KCRP to preclude wind shear (925 mb winds less than 30 knots and surface winds between 6-10 knots), but still could have it at KALI where the low level jet is best (thus kept it). Have gone on the high side of guidance (warmer than most all options), thinking we'll be well above 100 west (104-105), and in the mid and upper 90s east. The drier air will keep pops minimal tonight, and despite the upper level low tracking across the region, it should not have any moisture to tap into.
Otherwise, sub-tropical upper level ridge over the dessert southwest is expected to move to the east through Monday. This convection is being aided by some weak upper level support due to a mid to upper level low in southeast Texas. Isolated shower activity could linger into the night time hours due to the aforementioned upper low still in the area. High pressure will continue to dominate the region and keep high temperatures in the triple digits for many locations across South Central Texas.
High pressure will extend from the Atlantic across southern Florida and into the Gulf of Mexico through the period.
328 AM CDT Sun Oct 29 2017 As of 8Z, a surface warm front is crossing western South Dakota with winds becoming westerly. As temperatures continue to rise, along with increasing LLM, the threat for freezing pcpn or snow is very limited. Pcpn amounts today will be very light based on the amount of dry air in the lower levels. A cold front will sink southward across the region this afternoon with wind becoming gusty from the northwest.
Most locations are seeing low to mid 20s this morning with the center of the Canadian high pressure right over the eastern Ozarks. about 10 degrees warmer than yesterday.
128 AM CDT Sun Oct 29 2017 Updated for 06Z aviation discussion 06Z TAF discussion: High pressure and VFR conditions will prevail through the period. Still expect much of the area to experience freezing temperatures early tomorrow morning. Cold high pressure will continue to settle over the region over the next 24 hours. My thinking is, if winds can calm down for just a bit, especially in the more rural areas, temperatures could drop to, or just below, freezing for at least an hour or two. On Sunday, high pressure will be firmly in place across the forecast area.
High pressure ridging will continue to bring temperatures around 10 degrees above normal today. A mostly dry cold front will drop down from Montana this afternoon through Monday morning bringing a slight chance of very light rain/snow showers mainly along the Montana divide/Wyoming border.
Upper-ridge to persist through Monday allowing for mostly clear skies areawide.
Some freezing drizzle was reported east of the divide with icing evidenced on webcams east of our area this morning. Most precipitation has come to an end with freezing drizzle no longer anticipated today, although some clouds will remain in northwest Colorado down towards Aspen before clearing out this evening. Looking at model soundings in this region, the profile would suggest a low potential of freezing drizzle with a little warm air above the surface and surface temps below freezing. However, the atmosphere is fairly dry when this occurs and does not saturate until after the entire profile drops below freezing. Having said that, chances for freezing drizzle look better as you head further east of the divide towards the foothills.
Areas of light drizzle continue over the remainder of the eastern Tennessee Valley as moisture is still being squeezed out of the lower part of the atmosphere. Temperatures are in the lower 30s to near 40 across the area but below freezing above about 3000 feet where patchy freezing drizzle or very light freezing rain is possible mainly this morning. As deep upper trough approaches the next few hours strong NW flow aloft will squeeze out enough moisture below 800 mb to produce areas of very light rain or drizzle lower elevations and light snow and freezing rain or freezing drizzle mountains. Accumulations of snow of a few tenths to over one inch possible in the higher mountains during the day. The highest elevations will stay below freezing. Northwest winds will be gusty in the higher elevations especially this afternoon and evening.
The aforementioned westerly downslope flow will draw warmer air into the region tonight helping to raise H85 temperatures up by roughly 10C. Should see lows only down into the 30s(F) across central Kansas tonight with the lower 40s(F) possible in extreme southwest Kansas. Relatively dry conditions will continue Sunday night into Monday as yet another cold front is projected to surge southward across western Kansas, in turn reinforcing the dry air mass already in place across the Western High Plains.
Temps tonight should mostly fall into the lower and mid 30s across the plains and the upper Arkansas River valley, with the San Luis Valley mainly seeing los in the 20s. Temps on Sun will be warmer than today. The high valleys should see highs in the 60s on Sun. The coldest air is forecast to remain east of the mts, so after a very cold morning look for highs in the 30s and 40s for the eastern plains, and mid 40s to lower 50s for the high valleys. As for snow amounts, the peaks of the Wets and Sangres as well as Pikes Peak may receive 3 to as high as 7 inches of new snow through Monday with this disturbance, while the lower slopes may see an inch or two.
Based on web cameras, it appears most of the freezing drizzle has ended in the mountains. Below about 10000 feet temperatures have climbed above freezing, so if drizzle is still occurring, it is not freezing. Ridging in the northwest flow aloft will shift off to the southeast Sunday morning. A cold front will enter northeast Colorado during the afternoon.
Nearly efficient radiational cooling has allowed some temperatures to fall to freezing or slightly below mainly in low lying areas in the Hill Country. There is a noticeable difference between valley and hilltop temperatures as the airmass begins to modify with readings about 15 degrees warmer on the hilltops than readings in nearby valleys. A southwesterly flow develops allowing for much warmer, though still below normal, temperatures than yesterday. Minimal moisture recovery is expected tonight with another round of well below normal temperatures, though much warmer than this morning as the airmass recovers.
The latest surface analysis and observations across the tri-state region show that the cold front has cleared the region at this hour, as surface winds have shifted to the northwest. Despite clear skies, cold air will continue to advect into the region through the day as the trough axis swings through later today, keeping high temperatures well below normal for today.
1226 AM CDT Sun Oct 29 2017 VFR conditions are expected to persist through the valid forecast period with high pressure in place at the surface across the state. Light and variable winds overnight will become south- southwesterly shortly after sunrise as the ridge of high pressure moves east and early morning heating begins to mix out the shallow nocturnal inversion. A cold front will bring winds around to the northwest again on Monday but that is beyond the current valid forecast period.
404 AM EDT Sun Oct 29 2017 A cold front with a developing area of low pressure will move northeast through the region today and tonight.
VFR conditions will continue at all terminals with cold front passing late tonight into early Monday morning. /Issued 248 AM CDT Sun Oct 29 2017/ Another chilly night in progress, although not as cold as last night, with a good chunk of the area seeing temperatures at or below freezing. Temperatures today will be much warmer under the influence of the southerly low level flow, with highs likely to be within a couple of degrees of seasonal normals in most spots. Yet another cold front will begin to move through the region after midnight tonight, clearing southeast Oklahoma and west central Arkansas by mid to late Monday morning. The front will initially come through without any precipitation, instead ushering in cooler temperatures and gusty northerly winds.
UPDATE ESRL HRRR and other high resolution guidance in very nice agreement for tonight regarding the band of light rain forecast to develop along a southward moving cold front. We opted to increase POPs a bit based on this higher confidence. A cold front will move through, bringing a chance of rain and breezy northwest winds. Warm air advection today has allowed temperatures to rise well above freezing. These warmer temperatures will hold on through most of the night and keep precipitation in the form of rain. With colder temperatures filtering in Sunday afternoon and evening some snow may develop around the Turtle Mountains as a secondary cold front moves into the north. Overnight Sunday there is a chance of light snow as the secondary cold front and an upper level wave rotates around the low in Canada.
335 AM CDT Sun Oct 29 2017 Mild weather today ahead of a cold front which moves into the area this afternoon. The cold front also ushers in cooler temps, highs Monday only in the 40s again.
WINDY AND MUCH COOLER TODAY WITH COLDEST TEMPERATURES OF THE. Cold front now moving into western zones of the area accompanied by light rain showers. Lows tonight will fall into the mid/upper 30s inland to the low/mid 40s coast.
347 AM CDT Sun Oct 29 2017 The upper-level trough continues to move slowly east early this morning, with the trough axis currently swinging through the Mid- South. Moisture on the backside of this trough has resulted in overcast conditions across much of west TN into extreme northeast MS. As this cloud deck slowly moves east, we'll see the freezing temps follow suit. Thus, no changes have been made to the Freeze Warning area, although it was broken into two segments to emphasize the temperatures remaining in the lower 30s over the northeast quadrant of the CWA. It's certainly not out of the question that some areas in the Tennessee River Valley remain above freezing this morning.
Morning clouds today will gradually give way to more sunny, but cooler weather today. High pressure over the region will keep dry and mild conditions over region through Tue. Then changes as low pressure over the Gulf of Alaska slides into the Pac NW, bringing few showers on Wed, with rather wet Thu and Fri.