Aikyam-Lab/Synoptic-Bench huggingface dataset:
Weak short wave/ mid-level circulation over southeastern Alabama in the base of the stationary upper trough seems to be concentrating the better convection to the west of the forecast area. Upper trough axis sharpens up a bit over the region Sunday and we should see better coverage of convection.
A vorticity lobe rounding the eastern side of the upper level ridge seems to be the primary forcing for a band of showers and isolated thunderstorms moving from north-northeast to south-southwest through central Texas this afternoon.
A weak cold front will drop south from the Great Lakes on Sunday, bringing rain chances mainly north of I-70. Diurnal convective activity thus far has been much more limited as compared to yesterday, confined so far to the ridges just east of the CWA. This is due to less overall instability/MLCAPE with warmer air aloft, as well as drier air in the mid-levels. Isolated/scattered storms remain possible over our eastern ridges where instability and moisture are a bit more favorable, and PoPs continue to be concentrated there for the afternoon/early evening. Updraft strength should be weaker today due to the lower CAPE, and thus the severe risk is quite low.
The upper level ridge gets dampened by an upper low tracking across Canada, putting the northern plains in more of a northwest flow aloft. The majority of this forecast period will exhibit northwesterly upper flow as the region remains situated between a western CONUS upper ridge and an upper trough across the Hudson Bay region in Canada.
257 PM CDT Sat Aug 3 2019 A beautiful afternoon today as high pressure works in from the northeast. allowing temperatures to climb into the low to mid 80s.
Nearly stationary band of convection has been lingering across southeast KS is an area of 850-700mb convergence which is also in the axis of the highest PW. Upper ridge will continue to amplify over the Rockies on Sun with better upper forcing shifting southeast east of the forecast area. Both ECMWF and GFS agree on lifting some remnant monsoonal energy over the upper ridge and into the area for Wed night into Thu and will maintain some pops to account for this.
This is all being driven by forcing from a upper low that is currently over southeastern Alabama slowly edging northward. Cooler temperatures are expected with highs only reaching the lower to mid 80s primarily.
A 500 mb high pressure system is centered over north Texas keeping a weak ridging pattern in place over our CWA through the period.
A warmer day as highs reach the lower 90s west and 85 to 89 east.
Satellite imagery shows a few convective build ups over the higher terrain but nothing so far that shows any promise of strengthening into anything precipitable. Ridge axis nearly overhead also lends itself to quite warm temperatures through early week.
1149 AM MDT Sat Aug 3 2019 The upper-level ridge is expected to shift a little bit westward today, which will bring the main monsoonal moisture plume to the west as well. Highs this afternoon will be near average, with the plains reaching the upper 80s to mid 90s, and the high valleys topping out in the mid 70s to mid 80s. Lows will get down to the low to mid 60s across the plains, and upper 40s to mid 50s in the high valleys.
307 PM CDT Sat Aug 3 2019 Showers and isolated storms were oozing south across the region thanks to the weak surface boundaries, mid level flow and an upper level short wave moving through the eastern edge of the upper level ridge. High pressure will move into the area Sunday as the ridge remains over the southwestern CONUS.
So on Sunday with very little to no upper forcing, would expect any coverage to be extremely isolated, and probably focused more inland away from the lake shadow of cooler/less unstable air.
336 PM EDT Sat Aug 3 2019 Updated at 207 PM EDT Sat Aug 3 2019 During the short term an upper low will lazily drift overhead while at the surface broad high pressure slides slowly southward from the Great Lakes and Midwest. Widely scattered showers and storms will be possible over southern Kentucky, under the trof and ahead of the high, with little if any rain chance elsewhere. Updated at 330 PM EDT Sat Aug 3 2019 Upper trough axis that has been hanging over the Ohio Valley is forecast to push eastward toward the eastern US coast at the beginning of the period.
208 PM CDT Sat Aug 3 2019 A weak cold front entered the Permian Basin today and will slowly drift south becoming stationary along the Pecos River valley tonight. Winds will become more easterly behind the front allowing for slightly cooler temperatures the next couple of days though that is just a comparative term as temps will still be above normal.
236 PM EDT Sat Aug 3 2019 Upper air pattern consists of a 500 mb trough on the west coast, a trough in the Canadian Rockies, troughing in the eastern U. and a ridge across the plains and Rockies. The trough in the Canadian Rockies heads east into the Canadian Prairies on Sun. The large-scale pattern starting Sunday will continue to be characterized by strong ridging over the Southwestern U. As warmer air advects in aloft on Sunday, we should get well into the 80s for highs with perhaps an isolated 90 degree reading, most likely over the interior west.
244 PM MDT Sat Aug 3 2019 Currently, isolated thunderstorms mainly confined to portions of Park County and the Palmer Divide, but expect isolated thunderstorms to also develop over the rest of the mountains and higher terrain areas of the Cheyenne Ridge as well.
A weak short wave trough embedded in northwest flow is spreading extensive mid and high clouds across the region with some showers from southeast SD into south central Iowa where higher moisture levels exist. At the surface, high pressure centered over the Upper Midwest continues to push dry and mild air into the CWA. Clouds associated with the short wave trough should begin exiting the area by late morning leading to plenty of sunshine today.
so the highest chances of seeing some precipitation will be at KOKC and KOUN. Watch will be continued with additional forcing possible into the afternoon as s/wv trough progresses south over the region, but any convection will likely be more scattered in nature (thus lower pops).
A theta-e boundary associated with an approaching cold front will enter the Devils Lake Basin around sunrise Sunday, with rain and thunderstorm chances increasing through the day.
Consistency run-to-run in the short term remains high enough that little in the way of the forecast narrative has changed, especially due to the now fairly persistent ridge in the western U. Hot temperatures are expected again today, but with cooling aloft with the flattening ridge, the resultant steep lapse rates could transition the showers into strong thunderstorms near the North Dakota border this afternoon. With the flat ridge, Canadian high pressure will slip some cooler air south of the border on Sunday. As the trough moving across Canada digs toward the Great Lakes, the upper ridge shifts slightly westward as it rebounds.
251 PM CDT Sat Aug 3 2019 An inverted trof remains located just east of the Mississippi River at this time. Dewpoints have pooled this afternoon along the trof with current readings ranging between 72 and 75 degrees occurring across much of West Tennessee and North Mississippi. The combination of the humid airmass, the trof, and daytime heating has allowed scattered showers and thunderstorms to pop across the region. Even with the loss of daytime heating, still expect some isolated to scattered showers to occur with the trof remaining over the area.
The region is still dominated by weak and broad high pressure. High pressure centered over the Great Lakes will continue to provide warm and dry weather to central Illinois today. Afternoon high temperatures will be a degree or two warmer than yesterday, mainly in the middle 80s. Overnight lows tonight will drop into the lower to middle 60s.
1221 PM CDT Sat Aug 3 2019 The large scale upper air pattern remains relatively unchanged since this time yesterday with an upper high/ridge centered near the four corners region and a weak elongated positively tilted upper trof stretching from the northeastern U. Temperatures today should be comparable to yesterday with highs in the lower to middle 80s. The lower troposphere remains dominated by high pressure centered through the lower Great Lakes resulting in northeast to easterly low level flow. Fewer clouds are expected on Sunday with highs a tad warmer than today.
NAM/GFS are in good agreement that an upper ridge that is an extension of the high centered over southwest CONUS will rotate slowly southeast from the Upper Midwest into Missouri/Illinois by Sunday night.
At the surface, high pressure remained in control over the local area, with dewpoints in the upper 50s and lower 60s as of 1 pm. Dewpoints are forecast to be slightly higher early Sunday, so expect morning lows to be not as cool as Saturday, with seasonable readings in the low to mid 60s.
A weak cold front is moving into the area resulting in areas of cloud cover and some isolated showers early this afternoon. A weak cold front will approach the KABI terminal early this evening, shifting winds to light by mid evening. /issued 442 AM CDT Sat Aug 3 2019/ (Today and Tonight) The upper level high will be centered over the Four Corners region today. A weak cold front is expected to move into the Big Country late this afternoon and evening, with the front making slow progress south to near or just south of the I-20 corridor overnight. Temperatures will be a couple of degrees cooler than yesterday, due to some increase in mid and high clouds, with highs 99 to 102 degrees. Lows tonight will be in the lower 70s.
206 PM CDT Sat Aug 3 2019 WV imagery this morning showing a large high pressure dome centered over the TX panhandle pretty much encompassing the majority of the CONUS with ridge axis extending well into central Canada.
High pressure looks to persist throughout the remainder of the weekend and provide dry weather and near normal temperatures.
The cold front responsible for the clouds and isolated precipitation was just moving into the northern Big Country as of 2 PM this afternoon. With that in mind, expect the southern half of the forecast area to still be warmer than normal with highs in the mid to upper 90s, but the Big Country should benefit by being behind the cold front with highs on Sunday in the upper 80s to low 90s.
A weak cold front will drop south from the Great Lakes on Sunday, bringing rain chances mainly north of I-70.
Satellite imagery this afternoon depicts mainly clear skies over northern California, with a few cumulus clouds popping up over the highest peaks. Conditions are forecast to remain dry, however; as monsoon moisture should stay out of the area as the high is over the desert southwest.
619 PM CDT Sat Aug 3 2019 High pressure will continue to bring hot and mostly dry weather to the region through the remainder of the weekend.
Expect VFR conditions to prevail across the Rio Grande Valley tonight into early Sunday morning as the 500mb ridge across the southwest United States and northwest Texas continues to provide subsidence across western portions of south Texas. A 500 mb high pressure system is centered over north Texas keeping a weak ridging pattern in place over our CWA through the period.
Clouds were limited to cumulus over the higher terrain. Isolated afternoon and evening thunderstorms are expected, mainly over the higher terrain.
857 PM EDT Sat Aug 3 2019 High pressure provides clear skies and pleasant temperatures Tonight through Sunday morning.
High pressure over the Four Corners Region will continue bring a moist southerly flow over northern Arizona through the weekend.
527 PM PDT Sat Aug 3 2019 High pressure returns with warming temperatures over the weekend.
644 PM CDT Sat Aug 3 2019 Showers and isolated storms were oozing south across the region thanks to the weak surface boundaries, mid level flow and an upper level short wave moving through the eastern edge of the upper level ridge. High pressure will move into the area Sunday as the ridge remains over the southwestern CONUS.
639 PM CDT Sat Aug 3 2019 A mild cold front has moved into the area this afternoon and has little impact. /issued 208 PM CDT Sat Aug 3 2019/ A weak cold front entered the Permian Basin today and will slowly drift south becoming stationary along the Pecos River valley tonight. Winds will become more easterly behind the front allowing for slightly cooler temperatures the next couple of days though that is just a comparative term as temps will still be above normal.
There is a low chance for an isolated shower or storm Sunday afternoon across portions of southern Lower Michigan, northeast Indiana, and northwest Ohio, but otherwise dry conditions will continue with highs into the lower to middle 80s again for Sunday.
/issued 251 PM CDT Sat Aug 3 2019/ An inverted trof remains located just east of the Mississippi River at this time. Dewpoints have pooled this afternoon along the trof with current readings ranging between 72 and 75 degrees occurring across much of West Tennessee and North Mississippi. The combination of the humid airmass, the trof, and daytime heating has allowed scattered showers and thunderstorms to pop across the region. Even with the loss of daytime heating, still expect some isolated to scattered showers to occur with the trof remaining over the area.
629 PM CDT Sat Aug 3 2019 A beautiful afternoon today as high pressure works in from the northeast. allowing temperatures to climb into the low to mid 80s.
A 500mb ridge remains centered over UT, CO, AZ, and NM with weak perturbations in the northwest flow over KS.
Nearly stationary band of convection has been lingering across southeast KS is an area of 850-700mb convergence which is also in the axis of the highest PW. Upper ridge will continue to amplify over the Rockies on Sun with better upper forcing shifting southeast east of the forecast area. Both ECMWF and GFS agree on lifting some remnant monsoonal energy over the upper ridge and into the area for Wed night into Thu and will maintain some pops to account for this. The lowest vsbys will probably be across central KS near the KHUT/KGBD and KRSL taf sites.
A subtropical ridge axis will build west across the north coast of Cuba and the Straits of Florida on Sunday. Otherwise, an Atlantic ridge axis will build westward tonight and Sunday across the north coast of Cuba and the Straits of Florida.
Updated at 207 PM EDT Sat Aug 3 2019 During the short term an upper low will lazily drift overhead while at the surface broad high pressure slides slowly southward from the Great Lakes and Midwest. Widely scattered showers and storms will be possible over southern Kentucky, under the trof and ahead of the high, with little if any rain chance elsewhere. Updated at 330 PM EDT Sat Aug 3 2019 Upper trough axis that has been hanging over the Ohio Valley is forecast to push eastward toward the eastern US coast at the beginning of the period.
Winds will shift the northeast at KABI this evening as a weak cold front moves through. The cold front responsible for the clouds and isolated precipitation was just moving into the northern Big Country as of 2 PM this afternoon. With that in mind, expect the southern half of the forecast area to still be warmer than normal with highs in the mid to upper 90s, but the Big Country should benefit by being behind the cold front with highs on Sunday in the upper 80s to low 90s.
Ridge axis remains well south of ECFL. The high pressure ridge axis will remain suppressed over the southern peninsula/FL Straits. High pressure ridge axis remains suppressed southward with initial SWRLY flow backing S/SERLY in the afternoon.
504 PM PDT Sat Aug 3 2019 High pressure returns with warming temperatures over the weekend.
A prominent mid/upper-level anticyclone located over the Colorado Plateau is forecast to persist through the middle of the upcoming work week.
Currently, isolated thunderstorms mainly confined to portions of Park County and the Palmer Divide, but expect isolated thunderstorms to also develop over the rest of the mountains and higher terrain areas of the Cheyenne Ridge as well.
953 PM EDT Sat Aug 3 2019 High pressure over southeastern Ontario will slide slightly east overnight, allowing a cold front to cross Lake Erie on Sunday afternoon and stall over the Ohio Valley.
The winds should behave as they should in a typical mid-summer diurnal environment under broad ridging and northerly winds aloft. A vorticity lobe rounding the eastern side of the upper level ridge seems to be the primary forcing for a band of showers and isolated thunderstorms moving from north-northeast to south-southwest through central Texas this afternoon.
Cooler temperatures are expected with highs only reaching the lower to mid 80s primarily.
1024 PM PDT Sat Aug 3 2019 High pressure returns with warming temperatures over the weekend.
Upper level trough remains situated across the eastern CONUS today with SW flow at the mid and upper levels across the region. PoP forecast is generally 30-60% with the higher PoPs inland. Highs today will again be in the lower 90s with the upper 80s along the coast.
With the increase in cloud cover/rain, afternoon highs look to climb mainly into the mid/upper 80s for most spots, which is a few degrees cooler compared to yesterday. Strong upper ridge axis will then remain in place over the SW states heading into the new work week, thereby maintaining NW flow across the SE region. High pressure will remain established across the Southern Plains of Texas and the Great Basin, with a broad upper trough over the Eastern CONUS.
1151 PM CDT Sat Aug 3 2019 Showers and isolated storms were oozing south across the region thanks to the weak surface boundaries, mid level flow and an upper level short wave moving through the eastern edge of the upper level ridge. High pressure will move into the area Sunday as the ridge remains over the southwestern CONUS. High pressure will remain over the area from Sunday night and into the day Monday. During the day Monday, models show the eastern edge of the ridge flattening with upper flow becoming more northwesterly than the northerly now occurring. This will be thanks to a weak trough that will help suppress the ridge.
Daytime highs today will be very similar to yesterday, although heat index values may climb a few degrees warmer.
Lows tonight will be in the mid 60s, with highs on Monday in the lower to mid 80s.
In the upper levels, one ridge is centered over the desert southwest while the Bermuda ridge extends over the east coast of the country. That leaves a weakness/trough between those 2 features, which is where the local CWA ends up. The eastern side of the ridge to the west is gradually eroding westward and allowing the trough to extend farther south into the Gulf of Mexico.
357 AM CDT Sun Aug 4 2019 Dry weather to prevail over the region both today and tomorrow as high pressure centered over the western Great Lakes extends southwest into our region. Temperatures will warm into the middle 80s today and upper 80s on Monday as high pressure slides east and southerly flow returns to the area.
319 AM CDT Sun Aug 4 2019 Short term concerns are extent of isolated convection this afternoon and overall development overnight ahead of surface cold front. Looking at water vapor imagery, we see what appears to be a weak short wave dropping southeast over the upper ridge into northwest MN. Various HIRES solutions have northern MN activity dropping south into the northern CWA and weakening/ending early evening before main development along the cold front drops in late tonight to the northern CWA. Cold front drops southeast with likely PoPs dropping south in the afternoon with the front.
Temperatures are mainly in the low to middle 70s and probably won't cool more than another degree or two prior to sunrise. A broad ridge remains in place across the Western US with a trough over and East of the Great Lakes. Guidance suggests the highest instability, over 2,000 Joules of CAPE, will be over West TN this afternoon, with generally 1,500 to 2,000 J/KG elsewhere.
This will be the area with deepest moisture coinciding with cooler mid level temperatures associated with exiting weak trough. While it does not look like we will see any significant strengthening of upper ridge, with mid-level heights only increasing slightly, we will see return to south/southwesterly lower level flow over a majority of the region.
Unfortunately, the incoming air will not be any cooler or less humid at the surface.
Day time highs will reach into the low to mid 90s this afternoon. Some areas like the canyon floor may reach the high 90s. Monday will be warmer with highs reaching mid to upper 90s, with the canyon floor likely to reach the low triple digits again. Going into Monday night the upper level high will move west a bit with northwest flow returning.
At the surface, high pressure remained in control over the local area, with dewpoints in the upper 50s and lower 60s as of 1 pm.
Given recent overachieving temps and continuing dry conditions across much of the area, will bump afternoon highs up to the high end of model guidance with the urban areas just either side of 90 and the rest in the upper 80s. Updated at 400 AM EDT Sun Aug 4 2019 A strong upper level ridge currently in place over the western U. However, a series of short waves sliding over the top of the ridge will bring the chance of thunderstorms back into the area after a dry start to the work week.
/issued 251 PM CDT Sat Aug 3 2019/ An inverted trof remains located just east of the Mississippi River at this time. Dewpoints have pooled this afternoon along the trof with current readings ranging between 72 and 75 degrees occurring across much of West Tennessee and North Mississippi. The combination of the humid airmass, the trof, and daytime heating has allowed scattered showers and thunderstorms to pop across the region. Even with the loss of daytime heating, still expect some isolated to scattered showers to occur with the trof remaining over the area. By Monday, the trof begins to move out of the area which will result in decreasing chances for convection.
249 AM CDT Sun Aug 4 2019 This morning, an upper level ridge has continued to persist over the Four Corners region, once again keeping our region in a northwest flow pattern. At the surface, high pressure is centered over the midwest with our region sitting on the southern fringe of the high pressure, resulting in light winds and clear skies across the area. A drier air mass will continue to usher in today as the aforementioned high pressure builds into Missouri. With high pressure and mostly sunny skies persisting into Monday, dry and warm conditions are expected to continue. Slightly more sunshine than Sunday and light southwesterly winds will provide the basis for high temperatures in the upper 80s to near 90 degrees across the area with heat indices in the low 90s.
An upper level ridge will remain anchored near the Four Corners region through the short term. Slightly cooler temperatures today given the increased cloud cover and isolated to scattered coverage of showers and storms.
Cooler temperatures are expected with highs only reaching the lower to mid 80s primarily. It should be warmer due to less precipitation coverage, with highs reaching 90 or 91 degrees in spots.
Elsewhere, somewhat drier/more stable air was in place ovr central and much of eastern AR, with an inverted sfc trof situated just east of the state. High pres aloft was centered ovr the 4-Corners region of the country, with broad upper trof ovr the ERN states.
Otherwise high temps will be about 5-7 degrees cooler than yesterday. By Mon PM subtropical ridge will be centered INVOF AZ/NM stateline allowing for a weak shrtwv trof to move s into SE NM/PB into Tue AM and the possibility a few SHRA/TSRA. Tue PM said ridge will build back ewd and forecast soundings exhibit substantial CINH. An increasing ewd presence of subtropical ridge indicates high temps will trend up Wed-Sun, when 100 degree reading will be commonplace.
For today, high pressure will be the dominant weather feature. Focus then turns to incoming cold front Monday.