Aikyam-Lab/Synoptic-Bench huggingface dataset:
Recently, activity has consolidated into a line of showers and storms moving quickly westward just south of the Lower Keys, and another line of storms moving NW across the offshore Gulf waters, with convection temporarily waning elsewhere across the service area. KBYX VWP data shows a nicely veering wind profile throughout the lower and mid levels, with ample momentum in the low levels where winds are averaging in the 15 to 20 knot range.
This afternoon, the broad upper ridge remained over the southern CONUS from the Mid-Atlantic through the Desert Southwest. A cutoff upper low was positioned off the coast of California with a trough progressing through the northwest US. There will be little relief from the muggy conditions tonight with lows only falling into the upper 70s and dew points staying in the low 70s. As the low-level jet strengthens tonight, there could be enough isentropic ascent for a few isolated showers or thunderstorms after midnight. Persistent moisture transport maintains dew points in the low to mid 70s creating heat index values approaching 110 degrees.
809 PM MDT Fri Jul 17 2020 Subtropical moisture moving across the area, led to high based showers and a few tstms, over the higher terrain and along portions of the I-25 corridor. There is expected cold front which will be entering the far northeast corner towards supper time Saturday evening. A cold front will push down into the forecast area Saturday evening, increasing precipitable water values and CAPE, with upslope flow that may keep convection going through the evening.
819 PM EDT Fri Jul 17 2020 Differential geopotential height rises supports surface ridging over the central Great Lakes tonight.
/issued 219 PM CDT Fri Jul 17 2020/ As we move into the heart of summer the pattern is well placed with an upper level high sprawled across the southern US. Without any boundaries and the upper high firmly entrenched at best an isolated storm may form, but the chance is too low to mention in any given location. Diurnal forcing appears enough to mention afternoon storms, additionally a trough will move across the central US before digging more deeply across the eastern US latter in the week.
855 PM CDT Fri Jul 17 2020 Storms developing along a boundary just across the border from Mobridge this evening. Cooler air will move in behind the front tonight. Low pressure will again move through the state on Saturday, potentially generating some showers and thunderstorms across eastern SD during the afternoon and evening.
However, easterly flow in the lower levels will continue to produce showers and a few storms over the adjacent Atlantic waters that will be able to push onshore along the coast into tonight. Persistent E to ESE flow, mainly in the 10-15kt range, with seas 2-3ft, possibly briefly reaching 4ft well offshore this weekend, however given the high bias of the wave models, wouldn't be surprised to them stay AOB 3ft through the period.
752 PM EDT Fri Jul 17 2020 High pressure moving to the southeast will continue to provide dry weather tonight.
Of interest for us in the westerlies to our north is a trough, seen starting to buckle the jet stream across the Pacific Northwest. This particular feature is of importance to us as it will drive a cold front south into the Central Plains late in the weekend, providing us with a chance for storms, and perhaps some relief from the heat. expect it to be hot and humid as the prevailing thermal ridge across the Plains States continues to wallow over Kansas and northwest Missouri. This setup pushed afternoon highs into the low to mid 90s today, with heat index readings hitting 105 degrees by the early afternoon hours, and we expect even more oppressive conditions for tomorrow.
A trough of low pressure continues to settle over the northern Rockies this afternoon.
The inverted trough in the Gulf of Mexico, which is responsible for this activity, will continue to move westward toward the Texas coast tonight and into tomorrow. Moisture will increase tomorrow as well as vorticity associated with the inverted trough.
the center of the Southern Plains ridge of high pressure continued to be more over Oklahoma compared to 24-hrs ago. passing high clouds will remain possible across Eastern Oklahoma and Northwest Arkansas while the center of the ridge is expected to hold over the region. keep the ongoing precip in the High Plains well west/northwest of the CWA tonight. With the ridge more over the CWA. Continued southerly low level flow should aid in keeping dewpoints in the upper 60s to lower 70s by early Saturday morning which should hold low temps in the low to upper 70s for most of the CWA.
Weak upper ridging holding tonight, and CAM's showing very little if any additional development through 12z. Upper high to remain in control with the center located across the western Carolinas.
This will likely lead to better areal coverage of storms with the highest POP's south of the I-4 corridor.
637 PM CDT Fri Jul 17 2020 Heat and humidity will continue to increase for Saturday, with highs in the low to mid 90s expected, along with heat index of 105 to 110.
A mid level trough was in place over eastern Colorado this afternoon. ahead of the trough southerly winds were common across western KS. In the closer term - the western edge of the heat advisory may have trouble reaching the criterion apparent T of 105, however the higher dew points in the 70s farther west will give it a shot. Saturday there will be a better setup for thunderstorms as a cold front begins to push southward out of Nebraska and convection at some point is likely to unzip near the cold front dryline interface in northern Kansas.
/22/ Prior discussion below: Tonight and Saturday: Very little in the way of convection has been able to manifest this afternoon as lower PWs underneath the mid/upper level ridge has spread over the area. This will be the rule again Saturday as this ridge remains draped over north MS and continues to suppress convective development. While most areas are seeing heat indices in the lower 100s this afternoon, some mixing of drier air down from aloft has made it seemingly more difficult to reach 105.
800 PM EDT Fri Jul 17 2020 Surface and upper level ridging will remain over the region for the next couple of days so thunderstorm threat appears low. Overnight expect mostly clear skies and light winds will lows generally in the low to mid 70s. Saturday and Saturday Night: An expansive upper level ridge will weaken just slightly over the area as the center of the ridge shifts slightly farther to the west. At the surface, a weak lee side trough will be in place across the area. High temperatures in the mid 90s and dew points in the lower 70s in many areas will result in heat index values of 100-104F. Nighttime temperatures will be mild, with lows in the lower to mid 70s.
Dewpoints were as low as 38 at Alliance, while across the east as high as the lower 70s. Heat index values have dropped to the lower 90s as of 8 PM CDT, so the current heat advisory will be allowed to expire. On Saturday, the models remain in very good agreement warming 850MB temperatures to 30C to 34C south of an advancing cold front. In addition, A slight chance for showers and thunderstorms near and east of a line from North Platte through Bassett along the leading edge of the cold front. The upper level ridge will remain centered across the Southern U.
Upper air conditions show the high wobbles a bit to the west this weekend, which will introduce some capping and steering flow that may suppress convection that forms north of the Mogollon Rim. Expect scattered thunderstorms across the area this weekend, with the best chances for wetting rainfall located over the higher terrain of the White Mountains and Mogollon Rim.
Strong ridging aloft will continue to assert itself across the region during the period. This, combined with dew points in the low to mid 70s, will result in afternoon heat indices between 100F-105F, with index values peaking closer to 105F in the Delta. Quiet conditions are expected tonight, as lows fall into the low and middle 70s. /19/ A rather stagnant weather pattern will be in place for the week as broad upper ridging will be in place.
Cold front being analyzed from Rapid City to just south of Sheridan to Yellowstone NP this morning. Cold front forecast to drop to near a line from Cheyenne to Laramie to Riverton by noon time today. Cold front currently over northern Wyoming this morning. Cooler temperatures and higher humidity behind the front will keep fire weather conditions in check east of the front. gusty west winds and warmer temperatures will create critical conditions over Carbon County.
Weak upper ridging holding tonight, and CAM's showing very little if any additional development through 12z.
1201 AM EDT Sat Jul 18 2020 Differential geopotential height rises supports surface ridging over the central Great Lakes tonight.
317 AM CDT Sat Jul 18 2020 (Today and Tonight) Water vapor imagery shows a flattened upper level ridge stretching across much of the southern CONUS this morning.
Given the above will go with some slight chance PoPs today across a little more than the southern half of the area, with the highest PoPs in the afternoon when instability is maximized.
A decent cold frontal passage during the day will cool temperatures somewhat from today, with maximum temperatures in the upper 80s to middle 90s at lower elevations. With a low and mid level theta-e ridge axis setting up across our eastern counties and adequate low and mid level moisture along with low level mechanical lift from southeast winds, expect scattered afternoon and evening showers and thunderstorms, most numerous in our northeast counties from Lusk to Alliance.
Tonight through Sunday: The upper trough will slowly move out of the region and a northwest flow aloft flows in. High pressure will sit over the Northwest, accompanied by dry conditions and warming temperatures regionwide.
Dew points are in the lower 70s for most locations. The highest will be in the east where the dew points will be the highest. The one thing that will help the feel of the high humidity will be the wind from the southwest at 10 to 20 mph. Expect some showers and thunderstorms to develop along the cold front this afternoon and spread across the forecast area late this afternoon and into the evening hours. Temperatures will be cooler behind the cold front and highs will only be in the upper 80s.
With upper ridging still present over the area not expecting much in the way of afternoon convection. It is possible a few storms pop- up beneath the ridging but chances appear too low to mention at any location.
Due to the pressure gradient between the mid level ridge and short wave, winds have picked up at most locations and will continue with Red Flag Warnings that will remain in effect for much of central Wyoming, until 02Z tonight. This system will filter in some slightly cooler air, especially into northern and central sections, by 12Z Saturday. Dry conditions will continue through Saturday night with temps expected to fall about five degrees cooler by Sunday morning.
SHORT TERM (Now through Sunday): KBRO radar indicates isold conv firing south of the Rio Grande associate with the inverted 500 mb trough axis that has moved inland over the RGV/Deep South TX. This inverted trough will continue pushing west underneath the broad ridge axis in place over the southern U. This trough axis will combine with the daytime heating today to give the region a persistent potential for conv today. This general weakness in the ridging will allow for a little lower high temps today. As the inverted troffing drifts westward into Sun, the overall moisture levels across the region will decrease somewhat which may limit the conv potential on Sun.
The region will remain along the southern flank of a mid-level ridge with continued deep layer easterly flow. Compared to yesterday, the low to mid-level mean flow (0-3 km) will be weaker, which will allow for a more robust gulf sea-breeze. With high temperatures in the lower to middle 90s and dew points in the upper 60s to lower 70s, heat indices will reach around 100 to 105 degrees today.
Fire weather remains a concern with RH values dropping into the low 20s.
Temperatures will be a bit cooler for today thanks to the increased cloud cover and the much needed precipitation. Rain chances will diminish tonight as the inverted trough moves west of the area. This will lead to slightly warmer temperatures for Sunday, with heat indices near 105 for the Coastal Plains. The inverted trough that has been influencing the region will drift west through the weekend as an upper level trough tracks across the Plains.
mid and high level clouds are expected to move into the area from the southwest during the day ahead of some troughiness in the 500mb flow. Isolated thunderstorms are possible east of a line from around McCook to Goodland and Kit Carson from mid to late afternoon into the evening where the better moisture profile works with afternoon heating and the weak upper troughiness approaching. Low temperatures are expected to be in the low to upper 60s. Low temperatures look to be in the low to mid 60s.
/issued 245 PM CDT Fri Jul 17 2020/ WV imagery shows the upper ridge still centered over north central Texas, although is has shifted slightly west over the past 24 hours, and extending east thru the Carolinas and beyond. Temps Sat will be a bit cooler than today, w/the warmest temps shifting to the nrn CWA as the ridge drifts north. A weak inverted trough over the Big Bend Area will bifurcate the ridge, developing a col over Texas, and this will help keep a lid on things, as well. Rain chances remain paltry under the ridge, with isolated chances of convection each day generally confined to the higher terrain out west, mainly due to upslope flow.
With a strong cap, continued warm air advection, and moisture advection into southern Wisconsin, temperatures are expected to increase into the low to mid 90s. Dewpoints are also expected to rise into the low to mid 70s.
Water vapor imagery and RAP analysis this morning places a ridge of high pressure across much of the southern plains and southeast US including the Tennessee valley. This ridge that has kept its grip across the region will again sit atop the area with upper level subsidence likely capping much of the convection. CAMS and deterministic guidance does show isolated convective development this afternoon but believe the best locations to see convective development will likely remain across the high terrain. Given the ridge placement directly over the local area, temperatures will continue to be very warm today. This along with dewpoints in the upper 60s to low 70s will create oppressive conditions with heat index values into the low 100s.
231 AM EDT Sat Jul 18 2020 High pressure building in will lead to mostly clear skies tonight into tomorrow morning. High pressure is building in with drier air advecting in. A cold front will trail into the Great Lakes from a deep low near James Bay Canada.
With at least weak forcing on southern periphery of northern Rockies trough late today into tonight, a little better support of showers and storms coming off the higher terrain and affecting far northern/western Oklahoma.
The 500mb ridge currently over the southern plains will continue to maintain strength through the first part of the weekend which will lead to continued hot, humid, and dry conditions for the area. The ridge will show some signs of weakening by Sunday thanks to a short wave passing across the northern plains Saturday night into Sunday.
219 AM CDT Sat Jul 18 2020 After a 10-day stretch with high temperatures at or above 100 deg F at Lubbock, it is very possible that the streak is snapped today as the high is forecast to reach 98 deg F with 850 mb temperatures near 29 deg C. Temperatures set for a bit of decrease beginning Sunday as the upper ridge that extends from the desert Southwest to the southeastern US develops a weakness over the southern High Plains courtesy of low-amplitude cyclonic flow across the central and northern Plains and a slow westward-moving TUTT over deep south Texas and northeastern Mexico.
/Today through Tomorrow/ Heat and humidity will continue to be the overarching theme for the short-term period due to upper-level ridging. By Sunday afternoon, a shift in the ridge will allow for better SE winds, and quick influx of increased vorticity.
Widespread high pressure will bring in hot a humid conditions this weekend, which could have heat indices into the 100s. A widespread high pressure system will keep conditions dry tonight with mostly clear skies. A broad high upper high will persist for most of the short term, which will usher in hot temperatures, reaching the mid 90s on Sunday. Aided by dew points in the low to mid 70s, heat indices have the opportunity to range from 100 to 105 degrees. Saturday, the high looks to relent some at the surface with a weak upper wave.
256 AM CDT Sat Jul 18 2020 No big changes to the forecast are in the works, other than guidance pushing temperatures a touch warmer today and Sunday afternoon.
Models are in agreement with an upper level ridge blocking much of a northward push of any upper level moisture. At the surface, there is a high over the central Atlantic, which is keep all the tropical moisture moving west, until it gets around the Bahamas, and the allowing the low level moisture to stream across South Florida. Simultaneously, the Atlantic ridge axis across northern FL will keep deep easterlies in place, further aiding in abnormal atmospheric moisture at 1 to 2 standard deviations above normal, or in the 90th percentile.
1129 PM MDT Fri Jul 17 2020 Scattered showers and thunderstorms have developed over the higher terrain as a result of peak heating. Tomorrow the midlevel high pressure is still expected to split from the plains and move over the region, which means deeper westerlies into our area and drier air as the moisture plume is forced to the east. The drier conditions will again push afternoon temperatures upward with upper 90s to triple digits returning to the lower deserts.
227 AM EDT Sat Jul 18 2020 High pressure builds in through the first half of the weekend, with dry and very warm conditions on Saturday. Showers and storms arrive with a cold front Sunday night, before drying conditions associated with high pressure build back in across the region for the start of the new work week. High pressure builds in for this period. Low temps will range from the upper 50s across the higher terrain, to the low and mid 60s elsewhere. Maximum heat index reaches the lower 90s. Temperatures peaking in the lower to mid 90s for most areas with dangerous heat index values around 100. Cold front moves southeast into the lower Great Lakes Sunday night.
253 AM MDT Sat Jul 18 2020 Current surface map shows MCS outflow boundary backing into western South Dakota, with cold front across western North Dakota into northern Wyoming. Cold front continues to move through forecast area this morning. 3-4mb/3hr pressure rises behind the cold front will result in a period of gusty northwest winds.
Tonight Through Sunday Upper high pressure continues to stretch from Texas to the east coast. High temperatures will be in the lower to mid 90s for the weekend.
With afternoon temperatures in the middle 90s and dewpoints holding in the low to middle 70s, the combination of heat and humidity will become dangerous by this afternoon, with heat indicies in the 105-110 range for several hours. Thunderstorms are expected to develop along a cold front from SW/C Kansas into SE Nebraska this Sat evening, slowly pushing eastward overnight. Still, with some areas of potential morning rainfall and notable cloud debris, along with a weakening of the thermal axis over the area, enough signs suggest that Sunday will be a cooler day than todays readings. Additionally, a surface cold front should become quasi-stationary over northern Missouri, bringing some relief to northern sections of the state, and also serving as a focus for renewed convection during the afternoon and evening hours on Sunday.
AD Chattanooga Airport, TN 97 75 97 75 97 / 20 10 20 10 20 Knoxville McGhee Tyson Airport, TN 95 74 96 73 97 / 30 10 20 10 20 Oak Ridge, TN 96 73 96 73 97 / 30 10 20 10 20 Tri Cities Airport, TN 91 70 93 70 94 / 50 10 30 10 20.
347 AM EDT Sat Jul 18 2020 After a few weeks of westerly flow and mostly dry conditions across west central Florida ridging finally pushed back to our north. Ridging will stay to our north over the next seven days meaning the overall weather pattern won't be changing to much with above normal chances of rain each day.
332 AM EDT Sat Jul 18 2020 Conditions today again dictated by a gradually increasing upper height field, but with attendant surface ridging now displaced just to the east. Outside of t-storm potential, looking at another hot and humid day with dewpoints parked in the lower 70s. A slightly cooler and less humid mid summer air mass takes hold for the early week period, as the higher upper heights shift to the south. With that said, daytime highs will continue to reside on the warmer side of average - mid to upper 80s.
Isolated to scattered convection should develop with the highest risk of convection at KHUM between 18z and 00z. Will include VCTS wording at this location to reflect the higher risk of showers and thunderstorms today.
Early this morning the remaining cloud cover from yesterday's convection continued to drift across southern Missouri and Illinois as a light southerly surface wind kept temperatures generally in the lower to middle 70s overnight. These hot temperatures combined with dewpoint temperatures in the lower to middle 70s will once again produce dangerous heat index values between 105 and 110 this afternoon and early this evening. The forecast certainly gets a little more complicated as we head into Sunday, as the cold front will try to make a push south toward the I-70 corridor during the afternoon.
8-2" range across parts of the area on the backside of the inverted trof situated across south Tx, though satellite PW imagery does show some lower values over La which should partially advect into region later today.
Otherwise it will be dry through Sunday night, with the heat and humidity firmly established due to a strong upper ridge over the area.
Looking for highs in the low to mid 90s both of those days. While we will keep some small pops in for Tue into Tue night over eastern KS as a weak upper impulse departs the region, the overall trend through these extended periods will be for upper ridging to build across the Plains into the southeast CONUS. Added VCTS at KRSL/KGBD Saturday evening as storms develop in convergence ahead of the approaching cold front.
Atmosphere across the area is rather dry for this time of year, courtesy of ridging throughout the southeast US. The heat will continue with highs in the low/mid 90s and feels like temperatures reaching the low 100s. Large area of high pressure along with a strong upper level ridge will control much of the sensible weather through the weekend. Easterly and southeasterly flow at the surface will keep conditions moist at the lower levels through the period, but periodic intrusions of mid-level dry air from the northeast will keep rain chances mostly below seasonable norms.
The cold front associated with the system will be over the central part of the CWA around sunrise, then will gradually push eastward through the day. The storms look to quickly exit the area by early evening as the front continues east and high pressure settles in behind it. High temperatures today will range from the lower 80s northwest to the lower 90s southeast, with low temperatures tonight in the mid 50s to lower 60s. Highs on Sunday will be in the lower to mid 80s. As high pressure begins to exit the region to the east Sunday night, will see low pressure begin to approach from the southwest.