Aikyam-Lab/Synoptic-Bench huggingface dataset:
As the evening progressed colliding outflows worked on limited CAPE to generate additional showers and thunderstorms that moved across the lower elevations.
Weak disturbances aloft will crest the mid- level ridge axis over the northern Plains before diving southeast through into the mid MS Valley. Precipitation associated with these features will largely remain confined to the High Plains. A large-scale pattern characterized by ridging over western North America with downstream troughing in the east is expected to persist through the extended range. Similar to the short-term period, the best precipitation chances will be over the High Plains. A ridge of high pressure at the surface will remain in place from WI and MN into eastern NE through the TAF period.
517 PM MDT Thu Jul 27 2017 There is a weakly unstable air mass in place across the central High Plains today in the wake of yesterday cold front. The missing ingredient for thunderstorms is forcing, with no surface features and ridging aloft. Nonetheless, might see a few storms drift into northeast Colorado later tonight off the Cheyenne Ridge, however they will be weakening by that time and will dissipate after midnight. Will go ahead and carry some patchy fog overnight and early Friday morning with the high dew points and light upslope winds. On Friday, the upper ridge retrogrades just enough to allow the central Plains to get under more of a northwest flow aloft.
A sprawling upper level ridge of high pressure extends from eastern Arizona to Northeast Texas. The ridge is progged to expand and extend into SE TX by Friday morning. At the surface weak high pressure was located over the western Gulf of Mexico. Subsidence from the upper ridge, the lack of a sfc trigger and a reduction in moisture should lower rain chances below todays paltry coverage.
After 6Z, a fairly weak LLJ and theta-e ridge may be enough to develop elevated convection across the western CWA.
A sustained dry and cooler northeast flow will keep things quiet into Friday. Low level thermal trough sets up across the area with 925 temps in the teens celsius.
Though we are not anticipating any storms across the lower deserts today, increased thunderstorm activity is likely across southern Gila county late this afternoon and evening. High Res CAMs indicate storm activity will approach the lower deserts later this evening, but weaken considerably or completely fall apart. A significant inverted trough will move into southeast Arizona late tonight and slowly progress into south-central Arizona during the day Friday. It is possible we may have what should mostly be showers develop along the leading edge of the inverted trough just before sunrise, possibly affecting areas as far west as Phoenix sometime Friday morning. The aforementioned inverted trough will be a slow mover across the region as it remains nearly stationary across southern Arizona possibly through the entire weekend.
1216 AM EDT Fri Jul 28 2017 A cold front will cross the region tonight with scattered showers and isolated thunderstorms before midnight. High pressure will build in on the weekend bringing a sunny and dry weekend for most areas. Cold front just to our west will start to cross northern areas through the pre-dawn hours. The cold front is expected to stall along the coast into the midday w/some light showers lingering.
There is some diurnal component to this activity, although expect at least a scattering of showers and thunderstorms is remain most probable in vicinity to a approaching cold front later tonight. The big story is an end to the high heat and humidity of the last few days. Models are clear about the upper ridge retrogressing into the Rockys, leaving us in northwest flow. The climate prediction center is suggesting enhanced probability for cooler than average temperatures into early August.
824 PM PDT Thu Jul 27 2017 Seasonal summer weather through Friday with high pressure over the Southwest.
Wood High pressure moving slowly southward into the region tonight will bring quiet weather. A sustained dry and cooler northeast flow will keep things quiet into Friday. Low level thermal trough sets up across the area with 925 temps in the teens celsius.
Went slightly cooler than previous forecast which was roughly between the warmer MAV and the cooler MET.
937 PM EDT Thu Jul 27 2017 A cold front will sag southward across the region this evening as low pressure moves eastward across the lower Ohio Valley.
A combination of surface and upper ridging of high pressure will then control the weather for our area with mostly clear skies starting Friday night, and remaining dry until at least next Thursday. Don't expect that weak frontal boundary to move much more tonight, at least not until a mid level trough over MN amplifies and swings southward then eastward Friday afternoon moving that frontal boundary out of here as a cold front allowing high pressure in the are for the weekend. A gradual fill-in of the cloud deck should occur tonight as cooler temperatures on north winds overtake the area. A fairly sharp upper trough will drop southeast across the Great Lakes Friday and with it, a low threat for showers or thunder continuing in our far east and southeast counties at least through the morning hours Friday.
An extensive cirrus shield will linger across much of the region overnight, as sct convection continues to develop this evening along an old outflow bndry over Cntrl and Ern AR and spill WSW around the upper level ridge centered over OK/Wrn AR. /issued 407 PM CDT Thu Jul 27 2017/ The upper level ridge axis continues to hold strong across the southern CONUS with mostly middle 90s for highs this afternoon. Unfortunately, we've got one more hot day ahead on Friday before the cooler and drier air really begins to arrive.
Otherwise, outside of convection, winds will remain light with the cold front and associated north winds continuing southward. /issued 352 PM CDT Thu Jul 27 2017/ A few showers have developed over the past hour in the vicinity of a prefrontal trough/cold front in western and central Oklahoma. Additional storms are forming in the Oklahoma and Texas panhandles in advance of a mid level trough axis/vort max.
A cold front currently move into northeast Oklahoma will move through the area TAF sites by mid-morning Friday. The much anticipated cold front is currently located over northwest Oklahoma, extending northeast into southeast Kansas/southern Missouri.
High pressure anchored to the northwest of the Great Lakes tonight will sustain northeast winds across Se Mi. There is strong support from the 12Z model suite in showing amplification of the mid level short wave impulse now over nrn Minnesota into a compact upper low as it tracks across Se Mi (15-21Z) on Friday.
707 PM EDT Thu Jul 27 2017 A cold front will sag southward across the region this evening as low pressure moves eastward across the lower Ohio Valley.
A fairly strong upper level low moving through the Great Lakes region will force the upper level ridge axis to our north to shift southward and over Texas by tomorrow. At the surface, a weak cold front will move south into the Red River Valley, possibly reaching our northern counties by late in the day. However, with the ridge axis over the top of the area, do not expect thunderstorms to be able to develop along the boundary in our area. Otherwise, continued southerly flow at the surface, with lows tonight in the lower to mid 70s, and highs Friday in the familiar mid 90s to around 100 degrees.
Weak disturbances aloft will crest the mid- level ridge axis over the northern Plains before diving southeast through into the mid MS Valley. Precipitation associated with these features will largely remain confined to the High Plains. A large-scale pattern characterized by ridging over western North America with downstream troughing in the east is expected to persist through the extended range. Similar to the short-term period, the best precipitation chances will be over the High Plains. Ridge of high pressure at the surface will remain in place with winds mainly under 10 knots.
Temperatures on Friday will be cooler despite clearing skies, with highs in the mid 80s.
An abnormally moist atmosphere trapped beneath a large upper level high pressure will remain over Colorado/eastern Utah through at least Friday. these same warm and humid conditions beneath the under ridge will be in place for another round of t-storms by the afternoon.
644 PM CDT Thu Jul 27 2017 Strong high pressure over the region will suppress most cloud development and conditions at all area airports will be VFR through this period.
This boundary is the focusing mechanism for some convection which is being enhanced by the mid level low pressure area over the region. a cold front will drop across the coastal waters on friday and to central Florida Friday night.
626 PM CDT Thu Jul 27 2017 203 PM CDT One more afternoon of muggy conditions will come to an end as a large area of high pressure builds southeast into the midwest tonight. Ahead of the high weak upper level forcing atop the moist low level airmass has led to a few showers this afternoon along and north of the surface boundary across central IL, with some occasional gusty winds. KMD 1219 PM CDT High pressure expected to slowly build across the region through the weekend.
/issued 241 PM CDT Thu Jul 27 2017/ SHORT TERM (Tonight through Friday Night): Mid level ridge builds into the region while an inverted upper trough continues to shift westward across Mexico. Temperatures running a little warmer than anticipated out west today, so bumped up max temps across portions of the upper valley and ranchlands a couple of degrees for this afternoon. RH values fall into the lower to mid 20s across the western zones tomorrow afternoon, but 20 ft winds remain below 15 mph, and should preclude any significant fire weather concerns.
Isolated to scattered showers and thunderstorms will continue to develop overnight and into Friday in the vicinity of a cold front as it moves through the area. The cold front had finally entered into Northeast Oklahoma this evening. the cold front is forecast to move across Northeast Oklahoma and into Southeast Oklahoma and Northwest Arkansas by Friday morning. the drier dewpoints and cooler conditions look to be lagging behind the front a bit. lows in the low/mid 70s will remain possible.
/Issued 827 PM EDT Thu Jul 27 2017/ A cold front continues to sink southward through the Ohio Valley this evening into the overnight hours. Convection will increase again across north GA after daybreak as the aforementioned cold front approaches north GA. A more active day is expected on Friday as the aforementioned cold front approaches the region. This cold front will bring increasing thunderstorm chances especially across the northern half of the area as it moves southward. Short wave moving across southern Canada will dig into the eastern trough and develop a closed low over the Delmarva Peninsula.
With high pres at the sfc and aloft, rain chcs will remain minimal Friday while aftn temps will again be hot with highs in the lower to middle 90s and heat indices from 102 to 107. Temperatures in the low 90s, dewpoints in the mid 70s, heat index generally within a 100-105 range.
A cold front and outflow boundaries across Oklahoma has left a chaotic wind pattern along I-44, with more generally north breezes farther north, and light south winds to the south. Otherwise, outside of convection, winds will remain light with the cold front and associated north winds continuing southward. /issued 352 PM CDT Thu Jul 27 2017/ A few showers have developed over the past hour in the vicinity of a prefrontal trough/cold front in western and central Oklahoma. Additional storms are forming in the Oklahoma and Texas panhandles in advance of a mid level trough axis/vort max.
653 PM CDT Thu Jul 27 2017 19z/2pm surface analysis shows a cold front bisecting the KILX CWA. Thanks to cloud cover and relatively cool temperatures in the lower to middle 80s, LAPS data is showing CAPE values of only 1500-2000J/kg. Cold front will sink slowly southward tonight, pushing any lingering shower chances south of I-70 by midnight. Overnight low temperatures will range from the lower 60s far northwest around Galesburg. to the lower 70s far southeast near Lawrenceville. Front will sink into the Ohio River Valley on Friday as high pressure builds into the Upper Midwest. A cooler/drier airmass will flow into central Illinois from the north behind the departing front. with high temperatures remaining in the lower 80s. as a western CONUS upper ridge/eastern CONUS upper trough pattern dominates.
Dry northerly flow prevails across the northern Lakes early this afternoon, courtesy of large high pressure building slowly south out of Canada. Mid level flow configuration looks eerily similar to that which has been experienced much of this summer, with overhead northwest flow on front side of Intermountain West and high Plains centered ridge axis. One exception will be along the northeast lower coastline with lake modification keeping those coastal communities just a few degrees cooler.
829 PM EDT Thu Jul 27 2017 Increasing high pressure has led to deep column subsidence in the 7. Midlevel moisture progs suggest this midlevel subsidence is significantly compromising the structural integrity of the 700mb cold front. High pressure anchored to the northwest of the Great Lakes tonight will sustain northeast winds across Se Mi. There is strong support from the 12Z model suite in showing amplification of the mid level short wave impulse now over nrn Minnesota into a compact upper low as it tracks across Se Mi (15-21Z) on Friday.
Flying conditions will deteriorate over the taf period as a cold front approaches from the northwest.
Air mass is drying and stabilizing from the west this evening as the monsoon moisture and the upper trough from northern California exit into Montana and Wyoming.
/Issued 424 PM EDT Thu Jul 27 2017/ A cold front continues to sink southward through the Ohio Valley this evening into the overnight hours. Convection will increase again across north GA after daybreak as the aforementioned cold front approaches north GA. A more active day is expected on Friday as the aforementioned cold front approaches the region. This cold front will bring increasing thunderstorm chances especially across the northern half of the area as it moves southward. Short wave moving across southern Canada will dig into the eastern trough and develop a closed low over the Delmarva Peninsula.
In addition, an inverted trough is forecast to move into southern Navajo and Apache Counties. Flow around the inverted trough will cause storm mostion to switch to a more northerly direction, but will remain quite light - generally 10 knots or less. Over the weekend, The inverted trough to the south will turn the flow aloft to the southeast over the weekend. Some flash flood potential exists due to the high rainfall rates and slow movement of the storms.
526 PM MDT Thu Jul 27 2017 Current surface analysis shows low pressure over eastern MT, with frontal boundary stretching southeast into far western SD. Weak high pressure is centered over northeast ND. Upper level analysis shows weak ridging over the high plains, with trough off the pacific NW coast. Skies are variably cloudy across the area with temps mostly in the 80s over areas where it has been dry, cooler over rainy areas.
The only update this evening was to decrease shower/thunderstorm chances to just an isolated chance for most areas with the higher chances across southeast Montana. A weak front will cause winds to turn out of the northwest Friday morning, with ridging expected to build back over the region. Best chances will be over the higher terrain and western areas.
The majority of the precipitation is expected to fall over our south and eastern areas, but storms may still develop over the higher terrain in the west. Behind this disturbance, northwest flow aloft returns as a high pressure ridge moves back over the region. Period will be borderline Hot as the upper ridge pushes into the area through the weekend.
As of 20z, mid and upper level ridging continues to position itself across the central Plains. Comfortable conditions are expected for Friday with high temperatures in the low to middle 80s and LOW HUMIDITY! As we transition into the weekend the mid and upper level ridge looks to amplify across the central and northern Rockies, placing the plains within northerly to northwest flow. Very comfortable temperatures will continue through the weekend with highs in the lower 80s.
The low will quickly move to eastern Ontario by Sunday evening. Its weak cold front will barely reach central WI and southern MN Sunday afternoon as a marginal light wind shift.
On Sunday, upper ridge builds across CO, with very warm mid level temps pushing northward into the state. In general, blended model guidance looked too cool on temps, and nudged many locations upward toward warmer MOS numbers. Winds should begin to subtly increase by afternoon as lee trough deepens, though stronger winds will hold off until Sun night into Mon.
There does appear to be a setup for a weak downslope wind event across the Coteau region overnight, so sided with models such as the ARW/HRRR/NSSLWRF which nicely depict the higher downslope winds expected.
High pressure over the region will keep the precipitation away, and while there will be predominantly partly to mostly cloudy skies through the period, the bases are generally mid- to high-levels as the source of the clouds will be the Chinook Arch.
Skies will be clear, with overnight lows mainly in the lower 40s. Expect a beautiful day on Sunday, with clear skies, light winds and afternoon highs topping out in the lower 70s.
542 PM CST Sat Nov 25 2017 North Dakota remains under a broad ridge across the northern plains tonight. Mid/high level clouds will accompany this warmer air.
Lows tonight will be in the 40s (for most of the area) with highs in the lower 60s tomorrow. High pressure moves into the region early tomorrow and keeps the area generally clear/dry through the day.
339 PM MST Sat Nov 25 2017 Current surface map shows high pressure across the eastern Dakotas into the central plains. Upper level ridge builds across the area tonight and Sunday. Warm front lifts through western South Dakota Sunday afternoon with highs around 10F warmer than today.
A weak cold front, which currently extends from near Tyler back to the sw into central Texas will move through SE TX tonight.
Some high clouds were starting to spread into the region as of mid afternoon, as return flow begins on the back side of departing high pressure. A warm front in the eastern Dakotas will move quickly across the region tonight, as an area of low pressure moves across south central Canada. After the passage of a warm front, we will see a trailing cold front drop quickly across the region on Sunday.
High Plains lee troughing will eventually develop through the overnight and into Sunday.
An approaching cold front will bring an increased pressure gradient across southeast Oregon on Sunday afternoon, resulting in the potential for strengthening wind.
Winds are expected to gust near 20kts from late mrng thru aftn in advance of a weak cold front that will approach the region tomorrow aftn. Hence temperatures will begin to level off later tonight in the lower to middle 20s. Breezy southwest winds will carry warmer air into the area during the day as 925H temps warm to 5-7C. Could even be a little warmer if cirrus clouds do not increase as expected.
413 PM MST Sat Nov 25 2017 High pressure will persist over the next 36 hours bringing mostly clear conditions to eastern Utah and western Colorado with the exception of some high cirrus. Satellite indicates mid to upper level moisture moving onshore clockwise through the high pressure flow, but deeper moisture will not arrive until the start of the work week. Southwesterly flow will increase Sunday night as a strong trough moving onshore the west coast moves inland.
/issued 155 PM CST Sat Nov 25 2017/ Upper ridge centered over Baja extends into the region while a broad trough remains over the Eastern US.
815 PM CST Sat Nov 25 2017 A cold front that moved across the region earlier this afternoon was located well to the south and east of here. After a rather mild day with highs in the low/mid 60s (normal highs were 60/59 in Huntsville and Muscle Shoals respectively). With clear skies, light winds, and the surface ridging building towards the region, a rather chilly and possibly frosty night is in store, with lows in the mid 30s, a few degrees above running average lows.
849 PM EST Sat Nov 25 2017 A cold front is crossing the region this evening.
Drier and slightly cooler conditions expected Sunday night.
That combined with warmer temperatures from this afternoon and some high clouds will keep temperatures from getting as low tonight compared to the past two mornings. A cold front extends from the Canadian Maritime Provinces to Pennsylvania to northern Mississippi and Alabama into northeast Texas. At upper levels, a longwave trough continues over the eastern quarter of the country. Cold front really losing definition as it moves into the area, other than winds getting reinforced from the north.
Low temperatures in the low to mid 30s with southwest winds veering to the west at 10 mph or less. High temperatures warm back into the low to mid 70s which is 20 to 25 degrees above normal.
522 PM CST Sat Nov 25 2017 240 PM CST Quiet weather continues in the short term with high pressure ridging to move over tonight. While 925mb temperatures warm about 3C more than today, the starting point in the morning will be cooler than today.
1019 PM EST Sat Nov 25 2017 A dry cold front will pass through late tonight.
636 PM EST Sat Nov 25 2017 A dry cold front will move through the forecast area this late this evening into tonight.
Surface winds on the backside of the trough will shift to the southwest and west, bringing some warm air advection back into the area. Think there should still be enough daytime heating to get close to the freezing mark, but the north will still see much less of a rise than the southwestern counties, which should get into the mid 40s with some sunshine.
511 PM CST Sat Nov 25 2017 High pressure building into the midsection of the country this afternoon, and northwesterly winds are dominating behind the cold front from last night. Light winds become a little variable in the overnight hours as the ridge moves through the region. By morning, on the north side of the ridge, oriented from the Southern Plains up into the Ohio River Valley, the winds come around to more SSW to start the day. Sunday night, the lows remain in the upper 30s.
839 PM MST Sat Nov 25 2017 Broad high pressure aloft will build over region through Sunday. A dry northwesterly flow aloft will be over the region tonight with an upper level ridge stretching from the Desert Southwest then northward through central Utah. On Sunday, the upper level ridge will shift eastward, with its axis stretching from western New Mexico through central CO.
Sided closer to mos guidance with lows tonight given the strong sfc inversion noted in forecast soundings with readings in the lower to middle 30s.
821 PM CST Sat Nov 25 2017 Wk backdoor cold front bringing a few high clouds to the region, with skies likely becmg skc by daybreak. A dry cold front will continue moving South across the area and out of the region by late tonight. Weak back-door cold front making its way swd as well, and will be reinforced/pushed swd by another disturbance later tonight. Upper ridge to be squeezed ewd in response to a strong w coast trof as we move into next work week.
Chattanooga Airport, TN 38 60 33 60 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 36 56 31 58 / 0 0 0 0 Oak Ridge, TN 36 56 31 57 / 0 0 0 0 Tri Cities Airport, TN 30 52 29 55 / 0 0 0 0.