Aikyam-Lab/Synoptic-Bench huggingface dataset:
with accompanying thermal ridge crashing over the upper Midwest from MN through north of Lake Superior, into southern Canada. For Sunday, 850mb temps may be a degree or two cooler. very difficult to go any more than a degree or two cooler than persistence from today's highs. A deep upper low remains more or less parked over the Four Corners region of the CONUS. helping to dig a longwave trough/height falls from Manitoba all the way into the Baja of California.
350 PM EDT Sat Sep 23 2017 An upper level high pressure system across the Great Lakes into the Ohio Valley will keep above normal warmth in place through the weekend. Valley temperatures look to cool into the upper 50s to near 60 with ridges remaining in the low 60s. Will keep rain chances out of the forecast for now as the upper high nudges slightly south and east into the Appalachians, resulting in a minor uptick in upper height fields and similar afternoon temperatures in the mid 80s. The initial upper level high will be replaced by a southwest building ridge.
Wouldn't be surprised to see a few pop-up storms a little further north than we currently have indicated in our grids, especially over western areas, just east of the inverted trough axis.
Tonight into Sunday, the upper low currently positioned over the Florida panhandle continues to move west, ultimately settling over the lower Mississippi River Valley by Sunday evening. Aided by dynamic support from the upper low, showers and thunderstorms should become more numerous on Sunday than they've been the past few days, with activity starting offshore late tonight and gradually spreading inland throughout the day Sunday. Highs on Sunday remain a bit cooler than recent days given the greater coverage in clouds and rain, with mid 80's expected near the coast and upper 80's well inland.
Low pressure exiting east of the state will leave behind a few showers across far eastern Nevada through Sunday.
1126 AM MDT Sat Sep 23 2017 Overnight GOES-R water vapor loop showed a closed upper low over north-central NV within a deep amplitude trough occupying the Intermountain West. A surface cold front extended from northeast through southwest NE, central CO to a low near the UT/CO border.
1226 PM CDT Sat Sep 23 2017 Above normal temperatures continue today, although thicker diurnal cu and more efficient mixing of boundary layer moisture may keep heat indices in the lower to mid 90s (versus near triple digits of the past few days).
Upper level ridging will gradually shift eastward tomorrow, and flow aloft will veer to the southeast as a weak upper level low over the gulf coast region begins to influence the region. The hot and dry weather will continue across our region through mid-week before a strong cold front moves into the area.
1239 PM CDT Sat Sep 23 2017 A large upper low will continue to settle over the Great Basin today and central Rockies on Sunday, with downstream upper ridging over the Ohio Valley and eastern states. Gusty southerly winds and above normal temperatures will persist today into Sunday across our forecast area, to the south of a slow-moving cold front in Nebraska, and east of a lee trough/dryline near the Colorado/Kansas border. Widespread showers/thunderstorms will focus along the front and lee trough, mainly to the west and north of the forecast area through Sunday morning.
401 PM MDT Sat Sep 23 2017 Water vapor imagery shows the closed upper low spinning across eastern Nevada with good upper level divergence spreading over the CWA. Wet bulb zero heights and snow levels will remain around 10500 ft through the early evening, so any accumulating snows should be confined to the higher peaks of the Snowy Range through tonight. Upper low will move into central Utah by Sunday morning, with colder air aloft moving into areas west of the Laramie Range.
252 PM MDT Sat Sep 23 2017 Current surface analysis shows cold front now well south and east of the region, with very cool air in place. Upper level analysis shows large scale trough over the western US, with fast south- southwest flow over the Rockies into the Northern Plains. Wet weather is to continue through the rest of the weekend, with well below average temperatures, as the upper trough only slowly move east-northeast.
The large high pressure ridge to our northwest will drift east and be positioned over the eastern Great Lakes tomorrow, while an upper low near the Gulf Coast will drift west.
Clearing from the west today with relatively cooler temperatures and drier conditions by this afternoon.
1239 PM CDT Sat Sep 23 2017 Unseasonable warm weather will continue through the weekend as the region remains between the blocked high to the east and a digging trough to the west. High temperatures though will trend a few degrees cooler today as heights marginally fall and then again tomorrow as a weak wave induces clouds and perhaps a few spotty showers. though there are some questions whether the models are accurately advecting the western trough eastward too quickly given the weak Rex block over the east and meridional flow to the west.
305 PM MDT Sat Sep 23 2017 Northern and Central Wyoming will be on the western part of a low pressure storm system which will bring snow mainly to the mountains.
Intermittent tropical showers and a few storms will continue to stream over the area, but maintain poor coverage due to mid level ridging in place. Temperatures will continue a gradual trend "cooler" as the humidity increases and keeps the summer humidity and mid-upper 90s heat indices intact over much of the area Sunday.
A ridge of high pressure along the west coast is gradually getting stronger leading to a slow warming trend. Other than early morning freezing fog possible in the Sierra Valley and around the Truckee airport, benign weather is expected for at least the next several days. Overnight lows will remain quite cool with temperatures forecast to be below freezing for Sierra Valleys and in the 30s to around 40 degrees for most western NV communities.
128 PM EDT Sat Sep 23 2017 Strong upper ridging anchored over the region will maintain favorable aviation conditions through the period. High temperature records will be in jeopardy once again today, especially in the Flint to Tri Cities region as interior sections of lower Michigan remain capable of highs in the lower to mid 90s. The slightly cooler locations near the shorelines will also make another run at 90, especially metro Detroit with a little less influence from Lake Erie. This will be due to the core of the upper level ridge sliding eastward along the Atlantic coast as the long wave pattern begins some adjustment from strong amplification over the last few days.
The area remains in a very summer like pattern, pinched between a large trough out over the far western CONUS, and ridging just east of the Mississippi river valley, with then troughing within which are embedded hurricane Maria and the remnants of hurricane Jose. This wave is in the plume of best moisture and is in the low level jet, but there is less support at the mid and upper levels for stronger convection.
Current water vapor imagery along with 12Z upper air analysis showing high amplitude flow with riding in the eastern half of the CONUS and troughing in the west. 34 um water vapor channel has a closed low spinning over SE Nevada. the upper level system is progged to move very little with several models taking the 500 mb low from SE NV today to the UT/WY/CO border area by Sunday evening, then gradually filling and lifting the trough northeast, with its influence on us ending Tues evening.
315 PM MDT Sat Sep 23 2017 Closed upper level low over Nevada will slowly move eastward to NE Utah by noon Sunday. Because of the slow progression of this closed low, a band of showers picking up moisture from the Gulf of California will slowly trek eastward across western Colorado through tonight. with the closed low in Utah producing rain and snow showers over NE Utah by Sunday morning.
Will continue to see cool unsettled conditions over the next couple of days as upper trof slowly shifts northeast and fills in.
An area of low pressure may pull moisture back into eastern Arizona by the middle and end of next supporting some late season showers and storms. Surface dewpoints in the 20s are prevalent across much of the area with temperatures struggling to reach the mid 80s in the lower deserts. The broad trough responsible for the cool and dry conditions will linger across the intermountain West the next few days.
1206 PM CDT Sat Sep 23 2017 High pressure parked over the region will keep light Southeast winds over the area through sunset. Elongated upper ridge still stretches from the Great Lakes southwestward to central TX and will move little during the day today. A weak upper low will retrograde west Sunday as the main upper ridge finally begins pushing northeast. H850 temps finally back off some to around 16C so kept highs slightly cooler Sunday afternoon.
Upper level low pressure trough to our west will shift slightly eastward over eastern Montana over the next few days.
A cold front beneath a strong jet stream will pass through the area today and tonight. Behind the front much cooler air will move in Sunday. Dry air will filter in south of Interstate 70, however one more day of unsettled weather is expected to the north before the low exits the Rockies. Sunday will feature the coolest weather during the forecast period as the upper low and trough axis pass over.
255 PM CDT Sat Sep 23 2017 19Z water vapor imagery shows the upper trough is still over the western U. Upper ridging extended from north TX through the mid MS river valley and into the Great Lakes. At the surface, high pressure was centered over the mid MS river valley and a pre-frontal trough stretched from southwestern KS into eastern NEB. A decent cold front was located from northwest KS through northeast NEB. For tonight and Sunday, models continue to show a slow progression to the upper trough and the associated dynamics so that by Sunday afternoon the pre-frontal trough is across north central KS. With a little more cloud cover anticipated for Sunday, highs are expected to be a degree or two cooler than today with readings forecast to be in the in the mid to upper 80s.
Highs Sunday should be a bit cooler, but still quite warm, with upper 80s to around 90 forecast.
Weak upper level ridging will try to develop over the western Gulf between a deep upper level tough over the intermountain west and Maria to the east. The ridge will impart some subsidence over the region and despite some increase in moisture, rainfall will likely remain sparse through mid week.
134 PM MDT Sat Sep 23 2017 An upper level low pressure system will slowly move through the central Rocky Mountains through Sunday, leaving southwest and central Montana in a cooler and drier part of the system. Widespread frost will also develop overnight as temperatures drop to below freezing in many areas.
357 PM CDT Sat Sep 23 2017 Very little has changed with the overall position of the longwave trough over the West, with a downstream ridge firmly in place over the eastern states. In the lower levels of the atmosphere, a southwest to northeast surface boundary continues to stretch from central Nebraska through southwest Minnesota. In contrast, places like Huron, SD have been cloud-covered throughout the morning and sit under a shallow, much-cooler near surface air mass and northerly surface flow. high temperatures Sunday continue to show the stark differences in low level air masses, with upper 70s and 80s east of I-29, and much cooler 60s for Huron to Chamberlain.
349 PM EDT Sat Sep 23 2017 Another day within the impressive +590 dam ridge and yet another day of approaching and exceeding record highs. From a top down perspective, there are a number of indicators that suggests the heart of the upper level ridge axis will now drift through the cwa during the next 6 hours. For minimum values tonight, started with a straight persistence forecast but did massage some sources in that were keeping lows in the lower to mid 60s based on cooler dewpoints. The closed off center of the upper level ridge will roll eastward into portions of PA and Upstate NY on Sunday.
A deep upper trough has set up to our west allowing copious amounts of moisture to stream across the area at all levels.
The rest of Middle Tennessee has seen a pleasant but warm day with temperatures rising into the low 90s in some areas with most places in the upper 80s.
Most other inland locations were reporting temps in the lower 90's. While the upper pattern will remain similar across the CONUS through Sunday, the core of the upper level ridge will shift a bit to the east, with slightly lower thickness values across the forecast area.
352 PM CDT Sat Sep 23 2017 /Through Tonight/ An inverted trough along the Gulf Coast may generate a few showers across the eastern counties this afternoon with precipitation dissipating after sunset. 30 /Sunday through Saturday/ We will remain in an area of upper level ridging between a large upper trough over the western United States and an upper level low over the northeastern Gulf of Mexico for the next 24 to 36 hours. Highs on Sunday will once again be in the lower to middle 90s.
Upper level high pressure ridge should remain over South Texas. though we do start to get squeezed between advancing trough in the west and retrograding disturbance to the east.
Deep and strong western conus trof will continue to move only slowly east through the period. As a decent s/w lifts northeast out of the upper trof tnt, a developing llj will likely push that surface boundary back north, and in the process deliver additional moisture above the boundary layer back north into the cwa.
1209 PM MDT Sat Sep 23 2017 Water vapor imagery shows deep upper trof across the western CONUS with southwest flow across the Rockies into the northern plains.
/Issued 340 AM EDT Sat Sep 23 2017/ An upper trough continues over the se cwa and drifts into the northern Gulf of Mexico during the day as more or a weak upper low. For Sunday, the upper low drifts w along the gulf coast states with Hurricane Maria moving n over the western Atlantic. Medium range models continue to keep the region under a large, but not particularly strong, upper-level ridge through all but the tail-end of the period.
Widespread freezing temperatures across much of western Montana. Of note will be the lower valleys of northwest Montana and the Bitterroot/Missoula valleys. Some of these areas have reached the freezing mark however tonight's freeze will be more widespread and potentially freezing for several hours rather than just briefly touching 32 degrees. Temperatures may not quite make it to freezing in the Camas prairie but will lower enough to produce widespread frost with low temperatures in the mid 30s.
West and north of our area, several areas of rain and thunderstorms have developed ahead of a large western trough and stronger mid/upper level flow.
1241 PM CDT Sat Sep 23 2017 South/southeasterly winds continue in a very warm airmass, resulting in high temperatures once again in the low 90s.
A steady warmup is on the way for Northwest California as high pressure slowly regains control of the west coast.
Latest water vapor imagery shows a broad upper level low pushing west toward the area this afternoon, and this low is still expected to become centered over the region by tomorrow.
Cool and breezy conditions will persist this weekend as a low pressure system sits over the Great Basin.
A high amplitude/static upper level pattern over us now with a deep trough over the western CONUS and ridge over much of the east will gradually change with time as a short wave and associated sfc front move through the upper Midwest Tue/Wed.
159 PM EDT Sat Sep 23 2017 High pressure continuing to hold control, with only a few cirrus skirting the Bluegrass and Lake Cumberland regions. An area of high pressure and an upper level ridge will remain in control of the weather through midweek.
Right now there is an upper level trough in the western CONUS that is digging south.
High pressure to the east will keep very warm and dry conditions over the area tonight and Sunday. Wood Strong 500 mb anticyclone will slide slowly to the east of the region today into Sunday. 925 mb temperatures suggest highs should reach the lower 90s inland, near record highs. Highs Sunday should be a bit cooler, but still quite warm, with upper 80s forecast.
Surface wise, our area lies on the southern flank of a weak continental anticyclone over the mid Atlantic states and Hurricane Maria east of the north central Bahamas. Despite the close proximity of a deepening and digging mid latitude trough over the southeast United States and the Sunshine State, a light and chaotic wind will persist below 700 mb. With that, enough moisture in the low levels, leftover boundaries should allow segments of wet cloud line genesis and cells to migrate off portions of the large surrounding land masses. It appears our area will lie between a deepening mid latitude trough over the extreme southeast United States and the Florida peninsula and a western Atlantic ridge on the Straits of the Florida and the archipelago of Cuba.
315 PM CDT Sat Sep 23 2017 Another warm day across the Midsouth with a broad area of high pressure in control of the weather across the eastern half of the contiguous US. A weak upper level low centered over coastal AL and the FL panhandle will retrograde slightly west over the next couple of days.
255 PM CDT Sat Sep 23 2017 Surface and upper level ridging resulting in fair skies and continued south winds with very warm air. Temperatures at 2 PM CDT are in the lower 90s with both Moline and Cedar Rapids already breaking high temperatures for today.
The weather map this afternoon, high pressure dominates the eastern half of the country. A deep upper level trof is keeping south/southwesterly flow up the leeside of the Rockies and in the High Plains. more likely to be light and variable in the east with a lack of a pressure gradient closer to the ridge. another hot one, mostly sunny with max temps into the low 90s. Tomorrows highs in the low 90s will be very close to the apparent temp.
212 PM PDT Sat Sep 23 2017 A low pressure trough over the West will keep it comfortably cool again today. This will set the stage for sunny, warmer days, and clear, cool nights through the end of the month.
340 PM MDT Sat Sep 23 2017 Water vapor imagery shows the closed upper low spinning across eastern Nevada with good upper level divergence spreading over the CWA. Wet bulb zero heights and snow levels will remain around 10500 ft through the early evening, so any accumulating snows should be confined to the higher peaks of the Snowy Range through tonight. Upper low will move into central Utah by Sunday morning, with colder air aloft moving into areas west of the Laramie Range.
210 PM CDT Sat Sep 23 2017 High pressure was centered over the Ohio Valley early this afternoon, with a strong mid level ridge extending from the Great Lakes to Texas. An upper low was over the eastern Gulf Coast, FL Panhandle region. With respect to the upper low to our south.
302 PM CDT Sat Sep 23 2017 Isold convection ongoing across the region this aftn, as daytime heating and sufficient moisture overpower the the influence of the upper ridge.
614 PM EDT Sat Sep 23 2017 Strong upper ridging anchored over the region will maintain favorable aviation conditions through the period. Another day within the impressive +590 dam ridge and yet another day of approaching and exceeding record highs. From a top down perspective, there are a number of indicators that suggests the heart of the upper level ridge axis will now drift through the cwa during the next 6 hours. For minimum values tonight, started with a straight persistence forecast but did massage some sources in that were keeping lows in the lower to mid 60s based on cooler dewpoints. The closed off center of the upper level ridge will roll eastward into portions of PA and Upstate NY on Sunday.
SHORT TERM (Now through Sunday night): Well-amplified ridge over the Midwest will slowly move eastward as a deep trough over the western half of the U. RH values of 60 to 80% in the low levels along with precipitable water measured from the 12Z sounding of near 2.
A high amplitude/static upper level pattern over us now with a deep trough over the western CONUS and ridge over much of the east will gradually change with time as a short wave and associated sfc front move through the upper Midwest Tue/Wed. An upper low will drift westward underneat the ridge tomorrow into the lower Mississippi valley region with some energy moving across the Ozarks.
245 PM CDT Sat Sep 23 2017 A deep trough over the intermountain west is keeping a strong ridge over the east. This will keep the temperatures a little cooler but still above normal for this time of year.
upper low drifts slowly eastward through the Great Basin today and tonight, with strong S-SW flow aloft across Colorado. Clouds and precip will keep max temps today much cooler than the past several days, with 60s/70s at lower elevations, 50s/60s mountains, 30s/40s above 10k feet.
Expecting temps to top out in the low to mid 90s again today, with slight chances for isold aftn convection mainly across our srn areas.
Chattanooga Airport, TN 79 72 85 73 / 100 70 70 80 Knoxville McGhee Tyson Airport, TN 78 69 83 70 / 100 70 70 80 Oak Ridge, TN 78 69 83 71 / 100 70 70 80 Tri Cities Airport, TN 77 67 81 68 / 80 70 60 80.
645 AM CDT Thu Jun 22 2017 Forecast concerns in the short term will be thunderstorm chances/coverage as the cold front pushes southward through this evening. The h7 thermal ridge was over much of the forecast area at 12 to 14 degC and this led to highs in the 90s with 100 the hot spot at Albion. At 08Z, the cold front was north of FSD and near CDR and the warm front was near southern MN. The h5 closed low pressure system over Saskatchewan travels east into Ontario through 06Z. with 60 to 80m ht falls making their way into SD/MN as the h5 trough deepens. This will push the cold front southward toward Omaha/Lincoln by 00Z and northwest MO by 06Z. As the trough builds in.
Temperatures will be cooler today with upper 60s to lower 70s common. Upper trof digs into the area today with jet stream dropping south across the Beartooth then east along the MT/WY border. This will bring cooler air (about 10 degrees off of yesterdays highs) and a slight chance for showers/tstms (mainly for the mountains/foothills). Relative humidities will drop into the lower 20s combining with the gusty winds to bring elevated grass fire concerns to the area through this evening.
605 AM CDT Thu Jun 22 2017 Abbreviated discussion once again for ongoing severe convection approaching the highway 14 corridor. In addition, surface inversion is somewhat weak with temperatures hanging in the lower 70s. Storms work out of the region this evening leading to a cooler more tranquil overnight. Dominant feature of the forecast for Friday through the weekend will be cooler temperatures along with very comfortable dewpoints.
1149 AM EDT Thu Jun 22 2017 Moisture has become high in the southerly flow between high pressure off the Southeast Coast and tropical system Cindy near the western Gulf Coast.
1018 AM EDT Thu Jun 22 2017 Moisture has become high in the southerly flow between high pressure off the Southeast Coast and tropical system Cindy near the western Gulf Coast. A weak pressure trough in the forecast area today will become more diffuse Friday.
A dry high pressure system over the e pac will dominate the areas weather for the next several days.
739 AM EDT Thu Jun 22 2017 Moisture has become high in the southerly flow between high pressure off the Southeast Coast and tropical system Cindy near the western Gulf Coast. A weak pressure trough in the forecast area today will become more diffuse Friday.
757 AM CDT Thu Jun 22 2017 The ongoing thunderstorm activity across SD moves east this morning allowing cooler air into Nebraska.
Center of the low is now approaching the Toledo Bend reservoir.
1242 PM EDT Thu Jun 22 2017 High pressure will cross the region today.