Aikyam-Lab/Synoptic-Bench huggingface dataset:
Isolated showers developing over the coastal waters could make it into our coastal counties (mainly a small concern for LBX/GLS) by sunrise, but the main issue looks to be the weak cold front slow- ly moving toward SE TX (from the north) late Sun afternoon (after 21-23Z most likely).
Near the surface, high pressure is sinking slowly southward across the Northern Plains. Cooler, drier and more stable air was in the process of filtering into SW Kansas at midday, behind this morning's initial cold front.
246 AM CDT Sun Jul 11 2021 A seasonally strong upper trof will deepen into a closed low today as it drifts south over Missouri. Moisture wrapping around the cyclonic flow within the thermal trof will result low clouds and modest diurnal instability across eastern Kansas, so plan to continue to show modest chance PoPs for locations east of I-135, along with temperatures well below seasonal climo. The closed upper low and trof axis across the mid-Mississippi Valley and Ozarks will be slow to move through Monday.
Tranquil conditions will persist today into tonight as cooler/drier air continues to filter southward into the high plains of western Kansas while ridging aloft dominates the Intermountain West. Below normal temperatures are expected today as a northeasterly upslope flow reinforces a cooler air mass settled throughout the high plains of eastern Colorado and western Kansas.
Otherwise, high temperatures today should be about 5 degrees cooler than they have been running lately in the wake of the weak front. Monday morning will see our closed low over the middle Mississippi Valley with a high pressure dome across the desert southwest.
This is occurring along an area of slightly stronger low level SWrly flow of 20-25kts, well ahead of the large upper trough sinking SE into Cntrl/NE OK into Ern KS/NW MO. The overall radar trends as well as sfc ob reports suggest that the overall storm intensities have weakened compared to earlier this evening, as wind gusts have ranged between 30-45+ mph, with this trend expected to continue through the overnight hours as this complex eventually decays as the low level storm convergence weakens once winds veer more W late. Did not make many changes elsewhere given the higher dewpoints in place, and the expectation of low clouds developing late.
(This afternoon through Sunday night) Upper ridge centered over Srn NV this morning with a low over MN. As a trough extending from the low moves south across the plains today and Sunday it will trim off the east side of the ridge. Other than in the mountains the lows will be in the mid 60s to around 70.
A large upper trough will reside between the Rocky Mountains and the eastern seaboard today, with an embedded cutoff low looming over the mid Mississippi River region. This upper trough will gradually become squeezed into a highly amplified trough extending from the western Great Lakes to the ARLATEX region by late Monday afternoon between two building upper high pressure systems, one along and east of the Appalachian Mountains and the other over the central and southern Great Plains. Periods of heavy rainfall will occur mainly this afternoon into this evening northwest of I-65 while the upper trough is still at it's strongest.
As an upper trough digs down into the mid Mississippi Valley and forms a closed low, the surface front should shift southeastward this afternoon and tonight.
(This evening through Sunday) A cold front will enter the Big Country late tonight. Otherwise, look for little variation in temperatures as highs will remain in the lower 90s for Sunday.
120 AM MDT Sun Jul 11 2021 Area of high pressure being analyzed over Wyoming this morning with clear skies and light winds. Upper level pattern showing an area of high pressure over the desert southwest with ridging over Wyoming. Monsoonal moisture remains south of the high across northern old Mexico and southern Arizona. Warm and dry today and Monday as ridge of high pressure persists.
Isolated thunderstorms will then spread northeast from the mountains as a cold front moves into the area shifting winds to the north overnight. Not expecting much precipitation even right under thunderstorms as it will take a while for the low elevations to moisten up. Winds look to stay below Red Flag criteria outside of a few thermal gusts to 25 mph, as well as the higher terrain west where the hot/dry conditions will be less severe. Wind shift with the cold front arrives during the evening, past the peak hot/dry time, as well.
Winds in the mid and upper levels will increase across the western Panhandles as a jet streak works its way south and eventually southeast across eastern Colorado and eastern New Mexico around the Missouri upper level low. The upper level ridge may break down just enough to allow some mountain convection to move into the northwest CWA.
SHORT TERM (Now through Monday): Greatly-reduced precipitable water values, combined with weak 500 mb high pressure attempting to build over the BRO CWFA from both the west and east, will produce dry weather across Deep South Texas and the Rio Grande Valley through the period, a welcome change after a week of scattered to numerous showers and thunderstorms with both nuisance and flash flooding.
Additionally, the surface reflection of the short wave is pushing a cold front south through the eastern Plains, and this front will eventually dam up the most unstable air across the Lower Mississippi Valley by early Sunday morning. The exit of the low will finally bring some significant dry time to the forecast area.
1131 PM MDT Sat Jul 10 2021 Isolated showers on the plains to the east and southeast of the Black Hills will end later this afternoon as the upper low continues to move off to the east and drier air moves into the forecast area. An upper ridge to the west will then slowly shift eastward across the Rockies, bringing warmer weather on Sunday, and especially on Monday.
Issued by National Weather Service Springfield MO 337 AM CDT Sun Jul 11 2021 A deepening upper low will move southeast from over the Upper Midwest to the mid Mississippi Valley region today through Monday. While there is modest flow with this upper low, the instability factor should be less. Given the prospects for added cloud cover and convective chances with the upper low, we have highs in the lower 80s for today and Monday, close to available guidance. Westward progression of the Bermuda High early this week will keep high pressure in place over the east coast.
336 AM CDT Sun Jul 11 2021 A persistent upper level low will continue to spin just to our east through much of the day. By Monday, upper heights will begin to build east across the area as the previous mentioned upper low slowly moves toward the Mississippi River valley and upper level ridging builds in from the west.
With a very strong ridge overhead, there were some all-time records tied or broken today. Activity should diminish and head into the lower deserts this evening, with clearing skies from the north.
A ridge of high pressure over the Northern Rockies is pushing east this morning. As the ridge moves on, upper-level flow flattens and becomes more westerly, while a weak disturbance makes its way along the Canadian border with the Pacific Northwest. As this disturbance traverses the border with Montana, it will bring a cold front with it.
High temperatures today and Sunday will be in the upper 80s to low 90s, with the Lows in the low to mid 70s. Thunderstorms are possible in the afternoon with the highest PoPs (50%) in our GA counties. Mid-level trough to the northwest of the area will begin to retreat further north by Monday, with the subtropical ridge building back in from the east. this will allow the low-level flow to become more southeasterly.
In the upper levels, the region is situated between a trough to the west, ridge over the Atlantic and an upper low approaching the Florida east coast.
500 hPa ridging and high pressure at the surface will result in dry conditions Sunday. That said, ridging aloft continues resulting in another dry, pleasant day. Temperatures will be a few degrees warmer than Sunday, topping out in the lower to mid 80s.
Combined with the lift ahead of the cold front, showers and storm chances are anticipated to persist. With the convection and cloud cover, daytime highs will be a little cooler, reaching the lower 80s.
While the short range models indicate the storms diminishing early this morning, additional storm development is possible by mid afternoon with additional heating, and as a weak cold front moves into the Concho Valley and Heartland and dissipates. Highs will likely be a couple degrees cooler due to clouds and storms, but still warm in the 90 to 93 degree range.
High pressure is situated over western ND this evening and will slowly propagate south and east overnight. Currently, upper level trough continues to push off to the southeast, while an upper level ridge builds in from the west. Upper level ridge axis will continue to move into the Northern Plains tonight into tomorrow, resulting in a mostly clear sky over the next 24-36 hours. Will see near critical fire weather Sunday afternoon across the west, with min RH values falling into the lower 20s coupled with a steady southerly wind of 10 to 15 knots. Ridge is flattened Sunday night by an incoming S/WV. Extended models continue to strongly suggest a ridge of high pressure building across the western CONUS and Rocky Mountains late this period, eventually into our region the following week.
By Mon morning upper trough will extend from eastern IA through the Ozark region with subsidence across the forecast area. Normal highs for this time of year are in the low 90s. A mid/upper trough over the Central Plains will continue to dig southward overnight with some MVFR cigs developing across the area after 08-10Z. Some MVFR cigs may linger through the morning hours with some showers also possible under the mid/upper trough across mainly southeast Kansas.
152 AM EDT Sun Jul 11 2021 Upper air pattern consists of a 500 mb ridge in the western U. into the Rockies and then along the Gulf Coast with a trough in the Pacific NW and a trough in the central plains through New England. The transition of the system over the Central Plains is still expected to pinch out a closed low and become nearly vertically stacked in the short term.
An upper trough remains across the Mississippi Valley with upper diffluent flow and the potential for a couple areas of vort max PVA over the coming day. Unsettled weather will continue with high chance to likely PoPs area-wide with highest PoPs across the higher elevations of the mountains and plateau each day. Garuckas Chattanooga Airport, TN 87 71 84 69 84 / 60 50 80 60 70 Knoxville McGhee Tyson Airport, TN 88 71 87 69 86 / 40 30 70 50 60 Oak Ridge, TN 85 70 85 68 84 / 60 40 80 50 60 Tri Cities Airport, TN 88 68 88 67 86 / 50 30 60 20 50.
Temperatures will be cooler and dewpoints will be lower today across most of the area behind the cold front.
1003 PM CDT Sat Jul 10 2021 High pressure is situated over western ND this evening and will slowly propagate south and east overnight. Currently, upper level trough continues to push off to the southeast, while an upper level ridge builds in from the west. Upper level ridge axis will continue to move into the Northern Plains tonight into tomorrow, resulting in a mostly clear sky over the next 24-36 hours. Will see near critical fire weather Sunday afternoon across the west, with min RH values falling into the lower 20s coupled with a steady southerly wind of 10 to 15 knots. Ridge is flattened Sunday night by an incoming S/WV. Extended models continue to strongly suggest a ridge of high pressure building across the western CONUS and Rocky Mountains late this period, eventually into our region the following week.
305 AM CDT Sun Jul 11 2021 Early this morning, some weakening scattered showers and isolated thunderstorms were located along a southeastward moving cold front extending from far southwest Missouri into the Rolla area, generally south of the I-44 corridor. Lows this morning will bottom out in the low to mid 60s. A much cooler day is in store for today as a closed upper level low churns overhead. High temperatures will top out in the 70s for the majority of the area, though south central Missouri could touch the low 80s. Lingering overnight cloud cover tonight will keep lows relatively more mild in the low to mid 60s. The upper level low will barely budge on Monday, leaving a similar pattern of cool and cloudy weather over the CWA similar to Sunday.
Latest GOES 16 water vapor imagery depicts a deepening mid-level trough over northern Missouri, acting to force the Subtropical Ridge back west and over southern Nevada. Thunderstorms are ongoing along a southward advancing cold front over the Red River Valley in north Texas, with just a few isolated showers over the Rio Grande Plains in our neck of the woods. Over the next 24 to 36 hours, this trough will continue pushing southward, allowing a rare July cold front to make its way southward into Central Texas. The current thinking is that the aforementioned cold front will hold up just short of making it into our CWA, as daytime heating and moist, south-southeasterly low-level flow act to stall this frontal boundary out just north of our area before it washes out Monday evening.
Another round of precipitation currently lifting out of central Indiana should have a better chance of maintaining as it is associated with short wave energy ejecting from closed upper low and on the nose of developing LLJ. 00Z HREF along with forecast soundings not indicating much destabilization over our area this afternoon as upper low continues to dig further south which would tend to suppress associated surface features as warm front will struggle to make much northward progress today. Will therefore tie best precip chances with 850mb warm front which lifts up into northern Indiana this afternoon. Surface and upper low finally begin slow northward movement Monday. This will lift surface warm front into southern lower Michigan and allow for decent destabilization in the warm sector for our area Monday afternoon with HREF mean CAPE 1000-1500J/kg.
A large upper trough will reside between the Rocky Mountains and the eastern seaboard Sunday morning, with an embedded cutoff low looming over the mid Mississippi River region. This upper trough will gradually become squeezed into a highly amplified trough extending from the western Great Lakes to the ARLATEX region by late Monday afternoon between two building upper high pressure systems, one along and east of the Appalachian Mountains and the other over the central and southern Great Plains. Periods of heavy rainfall will occur mainly Sunday afternoon into Sunday evening northwest of I-65 while the upper trough is still at it's strongest. Low temperatures tonight will remain on the high side of seasonal norms, only dropping a couple of more degrees tonight into the lower to mid 70s inland, with mid to upper 70s along the coast.
This pattern is expected to continue today as the upper level low is forecast to remain across our area. Temperatures will be cooler again today with the low in the area, With 70 forecast at MLI today, and 68 for a record cold high, we will be close to that record. If there are more breaks in the clouds than expected, then we may see slightly warmer temps than forecast. Upper level low remains in place across the area, bringing near daily chances of rain and storms.
100 AM CDT Sun Jul 11 2021 (This evening through Sunday) A cold front will enter the Big Country late tonight. Otherwise, look for little variation in temperatures as highs will remain in the lower 90s for Sunday.
Moisture may increase a bit early this week with an upper trough to the west and the Bermuda ridge to the east. An upper level low/trough will remain over the Mid MS Valley with an upper level ridge building into the eastern seaboard from the western Atlantic. At the surface the Bermuda high will keep a southerly flow over the area as low pressure remains quasi stationary over the Mid MS Valley. High temperatures will be in the upper 80s to low 90s with lows tonight in the low 70s. Upper level trough will remain over the central US through the short term with upper level ridging building over the eastern seaboard. At the surface the Bermuda high will keep southerly flow over the area as low pressure remains quasi stationary over the mid MS River Valley.
Moisture may increase a bit early this week with an upper trough to the west and the Bermuda ridge to the east. Seasonal temperatures continue with the overnight min temps in the low to mid 70s. Upper level trough will remain over the central US through the short term with upper level ridging building over the eastern seaboard. At the surface the Bermuda high will keep southerly flow over the area as low pressure remains quasi stationary over the mid MS River Valley.
As of early this morning, the upper low was centered over northwestern Missouri, with scattered showers stretching from northeast Kansas into northern Missouri. Northerly winds behind a cold front has ushered in cooler and drier air, with temperatures in the middle 60s. Very little change is expected today as the upper low slowly shifts eastward to northeast Missouri. As the upper low departs the area on Monday, rain chances end for most sections - outside of a slight chance of a few showers remaining over central/northeast MO.
Early this morning, some weakening scattered showers and isolated thunderstorms were located along a southeastward moving cold front extending from far southwest Missouri into the Rolla area, generally south of the I-44 corridor. Lows this morning will bottom out in the low to mid 60s. A much cooler day is in store for today as a closed upper level low churns overhead. High temperatures will top out in the 70s for the majority of the area, though south central Missouri could touch the low 80s. Lingering overnight cloud cover tonight will keep lows relatively more mild in the low to mid 60s. The upper level low will barely budge on Monday, leaving a similar pattern of cool and cloudy weather over the CWA similar to Sunday.
713 AM CDT Sun Jul 11 2021 348 AM CDT The main story in the near term continues to be the broad upper low meandering overhead.
/issued 309 AM CDT Sun Jul 11 2021/ SHORT TERM (Now through Monday): Greatly-reduced precipitable water values, combined with weak 500 mb high pressure attempting to build over the BRO CWFA from both the west and east, will produce dry weather across Deep South Texas and the Rio Grande Valley through the period, a welcome change after a week of scattered to numerous showers and thunderstorms with both nuisance and flash flooding.
A persistent upper level low will continue to spin just to our east through much of the day. By Monday, upper heights will begin to build east across the area as the previous mentioned upper low slowly moves toward the Mississippi River valley and upper level ridging builds in from the west.
Clouds will also be on the increase ahead of the trough and its mid level short wave support. A multicell line of storms sweeping east appears to be the most likely storm structure type, so gusty winds could be the highest impact.
Another day with afternoon high temperatures in the low to mid 90s is expected today - though PWATs are a bit lower today than yesterday, so it should feel slightly less muggy outside. An upper level ridge the Desert Southwest will extend into East Texas today helping to suppress most precipitation. To our north, an upper level low will be slowly moving through the Central Plains today through Monday night.
331 AM MDT Sun Jul 11 2021 Synoptic Setup: A large ridge juts out from the Dome of hot high pressure over the Intermountain West. This ridge runs northeast through Idaho, Montana, southern Saskatchewan and Manitoba. Today and Tonight: Ridge line will exit east mid-morning allowing a cold front to enter by the afternoon hours. With the passage of the cold front clear air from northern Alberta should clear most of it.
Strong high pressure will result in one more hot day across all of northern Arizona.
Broad cyclonic flow encompasses the region this morning with an elongated closed upper low pivoting within the base of this upper trough across the Lower Missouri River Valley. The low meanders south of the region for the day today before slowly lifting northward on Monday. The aforementioned upper low lifts northward and absorbs into an approaching northern stream wave by Monday night.
High pressure at the surface and aloft should result in dry and warm conditions today through Monday. However, the orientation of the upper level ridge over the region today, supports the advection of vertically integrated smoke from the north/east down over this CWA. This upper trof is forecast to be running through the northern plains on Monday, dragging a surface cold front into the far western CWA by the end of peak heating on Monday. When the period opens Monday night, there is a (probably dry) cold frontal passage occurring.
330 AM MDT Sun Jul 11 2021 Upper high centered over southern portions of Nevada and California with extension of the high building north and west of Colorado today. Temperatures will be a bit warmer today as 700 mb temperatures increase to +13c which will translate of 3-5 degrees of warming from yesterday. The trajectory of the high pressure ridge expected to carry the smoke from the west and right into Colorado.
522 AM MDT Sun Jul 11 2021 Area of high pressure being analyzed over Wyoming this morning with clear skies and light winds. Upper level pattern showing an area of high pressure over the desert southwest with ridging over Wyoming. Monsoonal moisture remains south of the high across northern old Mexico and southern Arizona. Warm and dry today and Monday as ridge of high pressure persists.
The models do show an increase in bulk shear this afternoon across the northwest counties, but the air mass will have already stabilized from the cooler temperatures north of the outflow boundary and widespread precipitation. A digging short wave trof just west of the MS River will produce another impulse tonight and expect showers with embedded storms to increase in areal coverage across the northwest counties overnight, with minimal rain chances south of I-20. The short wave trof will maintain a positive tilt through Monday, and keep Central Alabama in a zone of high PWAT's and weak lift. Therefore, rain chances will remain on the high side on Monday.
Due to this, have continued the Excessive Heat Warning for all areas below 6kft with the exception of the "cooler" Delta area. Stronger onshore flow is expected tonight and tomorrow which will bring cooler temperatures to portions of the southern Sacramento and northern San Joaquin Valleys, including areas near the Delta.
Models also seem to be underestimating the low level winds with this system, so slightly higher bulk shear and helicity values could also help to organize a few strong or isolated severe storms later this evening and overnight.
The Atlc high pressure ridge axis remains fixated across the central peninsula this morning. Aloft, a weak area of low pressure over the Bahamas is forecast to open up as a trough and move toward the WNW and will lie across the FL Straits and south FL later tonight and early Mon morning. Already cool aloft near -8C at 500 mb, this trough will help lower mid-level temps to around -11C by sunrise Mon morning. The Atlc high pressure ridge axis across the central peninsula/adjacent waters will slowly shift north over the next 24 hours.
This activity was moving NE on the SE quadrant of an upper low situated over IA/MO, and troughing extending south to near the Gulf Coast. Given the showers and clouds, have trimmed high temperatures a degree or so, now mostly in the lower 80s.