Aikyam-Lab/Synoptic-Bench huggingface dataset:
Cold front approaches from the west Monday morning. Stronger cold front and cooler conditions for second half of week. There could be a lull in precipitation overnight, before a cold front approaches from the west, to bring rounds of showers or storms into Monday afternoon. The cold front will sink slowly south allowing showers and storms to develop through the afternoon and evening hours.
1050 PM EDT Sun Sep 1 2019 Showers and storms will end tonight as low pressure completes passage.
700 mb temperatures will be about the same with forecast surface temperatures much warmer than todays. Pressure gradient and 3 hour pressure falls support breezy conditions for most of this period with the higher gusts occurring during the daytime.
As shown on water vapor imagery, a healthy amount of moisture is trapped under the ridge for at least half of our area, which is where we have included isolated to slight chance PoPs for the afternoon. The next forecast challenge is the movement of the ridge over the week. The GFS pulls the ridge back west, allowing a front to backdoor into the region over the weekend with rain chances. The Euro continues an expansion eastward and finally flattening into the weekend, blocking the front for all but our far northeastern zones. The movement of the ridge will also impact our highs. At this time, we have gone with a warmer and drier solution, as that has been the trend.
524 PM MDT Sun Sep 1 2019 Mid-level high pressure persisted over southern Colorado today with dry air circulating over the region from the west. The weather on Labor Day looks very similar to today as high pressure remains in place over southern Colorado.
1017 PM EDT Sun Sep 1 2019 High pressure will weaken north of the area as Hurricane Dorian moves slowly north along the Southeast U. Weak mid and upper level ridge over the region will slip east overnight as an upper trough over the Midwest moves east to the Appalachians.
Mid-level ridge expected to remain near 4-Corners, with 500 mb flow trending to northeast and east overnight.
It is another warm August afternoon across northwest California, but overall running a few degrees cooler than yesterday. The cooler temperatures are mostly due to an onshore push last night, with marine air filtering inland and lingering today.
An upper level ridge across the Four Corners region will expand east across the southern Plains Tonight and Monday. The stronger upper jet will round the ridge axis across the northern US and southern Canada. The low- level WAA will allow high temperatures to reach the upper 80s to around 90 degrees.
Otherwise, a hot and humid week for September is in store across eastern Oklahoma and northwest Arkansas as a strong upper ridge builds over the area.
The strong upper level anti-cyclone will remain entrenched over the western half of the United States.
349 PM MDT Sun Sep 1 2019 Mid-level high pressure persisted over southern Colorado today with dry air circulating over the region from the west. The weather on Labor Day looks very similar to today as high pressure remains in place over southern Colorado.
this low level moisture looks to remain in place with dewpoints in the 60s/70s which should keep temps from falling off too much.
Overall, the wind field and moisture profile indicates that a low pressure system is located south of the area in the low to mid-levels while another area of low pressure is located north of the area in the upper levels.
Weak trough moving through at 500mb at the same time.
247 AM MDT Mon Sep 2 2019 08z surface analysis had low pressure over south central MT with trough into south central WY. Quite moist air east of this trough with Td/s in the 60s. Finally, water vapour showed upper ridge over the four corners area with upper trough over BC/AB. Upper trough will zip into south central Canada by evening and into the Midwest overnight. Ahead of the front, low level thermal ridge peaks with MLCIN strong enough to preclude TSRA chances until late in the day. Storms may develop along the cold front in the far north/east by evening given MLCAPE/shear profiles. Breezy westerly component to wind expected ahead of cold front and northwest behind the cold front. Tuesday, much cooler and breezy weather expected given 850mb winds around 20kts and low level thermal trough.
Low temperatures will be in the low to mid 70s north of I-10 and in the mid 70s to lower 80s south of I-10. Based on the latest PWAT guidance, a surge in low level moisture will be moving into the local waters tonight and Monday as a low pressure system amplifies and moves westward across the Gulf of Mexico. Additionally, mid level high pressure over the Four Corners region is expected to continue amplify.
Settled, but warm and humid conditions will continue today, and for most if not all of the upcoming week as upper level high pressure will be in control.
1140 PM MDT Sun Sep 1 2019 Latest upper analysis shows a building upper ridge over the western half of the CONUS this afternoon leading to rising heights over the forecast area. If any strong storms develop, expect it to occur near the intersection of the convergence zone along the higher terrain of the Black Hills and then shift southeastward depending into the evening hours. On Monday, the upper ridge will break down over the northern plains as an upper trough drops out of the Canadian prairie provinces and affects the Dakotas. Tuesday will be much cooler and breezy/windy given boundary layer wind profiles. High temperatures will be around 15 degrees cooler than on Monday.
Winds will be gustier this afternoon and much more widespread, as a cold front approaches areas east of the Divide from southern Montana. Humidity values will be critically low, ranging between 7 and 10 percent for much of the lower elevations. As previously mentioned, winds will be higher, as mid- level gusts mix back down to the surface and the surface pressure gradient tightens in response to the cold front. Winds will reach 20 to 25 mph with gusts up to 35 mph for the lower elevations, while higher elevations will see winds of 20 to 30 mph with gusts of 35 to 45 mph during the afternoon.
May be able to cancel early as the ridge quickly gives way to southerly to southwesterly surface flow, steadily increasing temps through the morning and helping to evaporate residual fog after sunrise. With warm advection overspreading the area today, resulting warmer temps will approach seasonal values across central Missouri and above seasonal values near the Kansas/Missouri border. Unfortunately, more humid conditions will also resume beginning this afternoon through Tuesday as dew points climb back into the low to possibly mid 70s. For Tuesday, temperature trends will continue to increase as the warm sector deepens ahead of a cold front.
304 AM CDT Mon Sep 2 2019 06Z surface data has high pressure over the middle Mississippi Valley with a frontal boundary from the Ohio Valley into the southern Plains. If diurnal convection develops as far south as highway 20 during the afternoon then isolated showers and storms will be possible in the highway 20 corridor through midnight. Late tonight forcing will increase again ahead of the approaching strong cold front. Otherwise, southwest flow will transport very warm and humid air into the region ahead of an approaching cold front.
Weak trough moving through at 500mb at the same time. Ridging builds in for Monday and early Tuesday so dry and very warm conditions expected.
The quiet weather pattern should continue into tonight as the ridge over the Rockies continues to expand eastward. Winds will be light out of the southeast keeping the low level moisture plentiful and as a result dew points will fall into the low to mid 60s tonight and overnight low temperatures will fall into the mid to upper 60s. Tuesday should bring warm temperatures again with winds out of the southwest lowering the moisture and helping to effectively heat up the region ahead of a cold front which will move through Tuesday night.
The Subtropical Ridge currently centered over the Four Corners region gradually expands into the Southern Plains as a broad area of low pressure drifts west across the southwestern Gulf of Mexico. NHC has a 50 percent chance of the low developing into a tropical system. Due to subsidence and drying underneath the Ridge and ahead of the Gulf low, rain is not expected.
236 AM MDT Mon Sep 2 2019 Very little has changed in the pattern with high pressure still parked over the region. The result will be an increase in cloud cover across the region therefore highs should be slightly cooler on Tuesday.
After some early morning fog Monday, dry conditions will return and prevail through Tuesday as high pressure strengthens over the region. The threat for showers and thunderstorms will return again Tuesday night though as a cold front moves through the forecast area. Meanwhile, overnight lows tonight will be in the low to mid 60s. High pressure will strengthen over the region with decent subsidence through Tuesday. By Tuesday night though, a cold front will drop into the area triggering showers and thunderstorms.
High pressure will begin to build back into the area today and we will see the pw's drop quite a bit.
The lowest visibilities and denser fog will be along I-70 over central Missouri, but this fog will extend out in all directions. As the high pressure pushes east Monday into Tuesday a southern return flow will bring WAA into the area and increase our temperatures 4 to 5 degrees each day, with Tuesday having highs in the lower 90s and heat indices in the mid 90s. These summer like temperatures will not last long as a cold front will push through Tuesday evening, bringing a much cooler airmass into the region.
An upper trough will linger just off the coast through Monday and then move ashore on Tuesday.
Isolated thunderstorm may develop along a lee trough located from Montana to the Colorado/Nebraska border. Any storms that do develop along this trough will have a hard time sustaining itself as it moves east due to decent MLCIN. High temperatures will climb into mid to upper 90s for portions of western and southwest Nebraska, with the warmer temperatures across the southwest. Elsewhere, temperatures will range from the lower 80s across north central Nebraska to the lower 90s. The warmer temperatures will be short lived as a mainly dry cold front will make its way through the area Monday night into Tuesday morning.
352 AM CDT Mon Sep 2 2019 Upper level ridging will generally prevail across the southern and central plains through 10 September, with only occasional slight weaknesses in this ridge. An upper level disturbance will pass into the northern plains today and into the upper Midwest Tuesday, helping to push a weak cold front into western Kansas by Tuesday afternoon.
246 AM EDT Mon Sep 2 2019 High pressure will weaken north of the area as Hurricane Dorian moves slowly north along the Southeast U. Weak mid and upper level ridge over the region will slip east overnight as an upper trough over the Midwest moves east to the Appalachians.
Lingering clouds will continue to dissipate from northwest to southeast late this afternoon as southerly warmer air filters in. A warmer and more humid airmass will continue to surge into the region ahead of a strong cold front system shifting southward. First, a mid-upper level trough over the Rockies/western NE is expected to approach the MO river by sunrise (around 12Z Monday). The next period to monitor will be Monday night into Tuesday as a strong upper-wave moves out of southwest Canada, bringing the aforementioned cold front into the forecast area. Behind the cold front, cooler and breezy conditions filter in on Tuesday. Strongest winds are expected along and north of I-90 and over the Buffalo Ridge area. Temperature- wise, daytime highs will range from the lower 70s to lower 80s.
NAM elevated instability 4-panel prog suggests the higher chance of seeing convection would occur over the Coastal Range and Shasta Co mtns Tue nite and Wed as cyclonic flow increases over that region with the approaching closed low nearing the CA coast. JHM Little change to the short term forecast with another day of above average temperatures expected across the NorCal interior as high pressure continues to influence the region. Monsoonal moisture will advect northward due to the upper high located across the Four Corners region on Tuesday.
156 AM CDT Mon Sep 2 2019 A few storms did end up popping up yesterday afternoon with the upper trough overhead, and with the trough exiting to the northeast/weak northerly flow behind, there may be some showers and storms that develop mainly in the east today.
331 AM CDT Mon Sep 2 2019 The upper high currently situated over the Four Corners region will work its way eastward by mid week and settle over the FA. While the upper high will be situated nearly overhead into late week there could still be enough moisture available to allow for widely isolated shower/thunderstorm development across the region as possible weak waves rotate around the high. Models diverge heading into the weekend with the evolution of an upper trough across the West Coast.
1127 PM MDT Sun Sep 1 2019 Mid-level high pressure persisted over southern Colorado today with dry air circulating over the region from the west. The weather on Labor Day looks very similar to today as high pressure remains in place over southern Colorado.
The threat for thunderstorms will continue today mainly in the north today until a cold front moves through NE Montana. An upper trough will follow the cold front this afternoon and evening. The front moves to the east tonight and high pressure builds into the region which will diminish the winds. The high along with an upper ridge building into Montana will keep Tuesday dry with cooler temperatures.
Wind will generally be less than 10 mph through the period all sites, and gradually veer to a southeasterly/southerly direction in response to deepening low pressure through the Plains. this low level moisture looks to remain in place with dewpoints in the 60s/70s which should keep temps from falling off too much.
/Today through Tuesday/ Dominant upper level ridge out west will continue to build/expand eastward across much of the central and southern U. Overnight temps will drop back into the lower to mid 70s under mostly clear skies and light winds. Tuesday looks to be a near repeat of today with the center of the upper ridge edging a bit closer as it shifts eastward from the Four-Corners Region out across the Rockies and into the Plains by mid-week.
A weak and dry cold front moves through Tuesday night.
A rather persistent pattern continues, with an upper ridge to our west and a low amplitude trough in the eastern US.
Upper level high pressure will remain over the Four Corners through the short term providing northwest flow aloft, near the surface, high pressure will build into the region from the north.
Dewpoints are also forecast to climb into the lower to 70s today, resulting in very humid conditions with heat index values in the mid to upper 90s for a few hours this afternoon. There is a cold front moving into northeast NE tonight, and then through the area on Tuesday. Highs Tuesday will be impacted by the front, only in the lower 80s north of it, but still in the upper 80s behind it.
253 AM EDT Mon Sep 2 2019 Updated at 252 AM EDT Mon Sep 2 2019 A weak cold front is starting to push into southern Indiana early this morning. Tonight, skies should gradually clear out and winds slacken as high pressures passes by to the north and northeast.
North and Central TX airports will remain underneath the SSE periphery of the upper ridge centered over the Four Corners/Rockies. At the surface, a broad high pressure cell centered over the Ozarks and Lower MS River Valley will remain extended southwestward into the area. /Issued 229 PM CDT Sun Sep 1 2019/ /Tonight/ North and Central Texas currently resides beneath the eastern edge of a mid level ridge, which is anchored over the Four Corners region for now. A weakness in the ridge over Central Texas is enough to allow for the development of isolated storms this afternoon, primarily south of I-20.
Labor Day is looking hot and dry, with highs in the low to mid 90s and mostly sunny skies.
The strong upper level anti-cyclone will remain entrenched over the western half of the United States. At the beginning of the forecast period, a cold front will be moving out of Wyoming and across eastern Colorado Tuesday morning.
An upper level ridge covers most of the CONUS with a trough along the eastern seaboard. It is this trough that will allow Hurricane Dorian to gradually turn more toward the north today. Highs will be in the lower 90s.
245 AM CDT Mon Sep 2 2019 A couple days of late Summer heat will return before a modest cold front moves south across the area late Tuesday. A significant upper trof will drop southeast from south central Canada across the Upper Midwest and Great Lakes on Tuesday. The associated surface cold front looks to reach roughly just south of the I-70 corridor by mid-afternoon.
Building high pressure will return dry weather for tonight and Tuesday.
Record or near record highs look a good bet over the lower elevations Monday as sunshine and dry air allow temperatures to warm well into the 90s. The front should edge back east Weds allowing for warmer temperatures to return over the plains.
Monday-Monday night: Main forecast focus is still on severe potential as a much stronger trough moves in the region (generally depicted as negatively tilted) and strong forcing/shear environment overspreads our CWA. Further north of warm front/stalled front an MCS should develop and move in a east- southeast direction, and there is some concern of QLCS features due to strong orthogonal shear component and at the very least widespread heavy rain and strong winds. Cold front moves through early Tuesday bringing gusty northwest winds during the day and some chance of light rain showers, mainly within Minnesota. Cooler air mass filters in behind the front keeping high temperatures in the 60s region-wide.
152 AM CDT Mon Sep 2 2019 The overall H5 flow pattern will remain a ridge invof the Four Corners region, with a trof across the east U. High pressure will build south and into the area today, with the ridge axis still over our area tonight. Tuesday will be dry as high pressure moves south ahead of an approaching cold front, that will move from NW to SE across the area Tuesday night.
Some of the high resolution models continue to insist some showers/thunderstorms will be developing across parts of our coastal counties before sunrise, and have low rain chances in that area for today. It will become increasingly warm as the week progresses with mid/upper level high pressure building into the area from the northwest and north. We continue to monitor a broad area of low pressure over the south-central Gulf of Mexico. The most recent National Hurricane Center Tropical Weather Outlook says gradual development of this system is possible during the next few days while the low moves slowly westward across the south-central and southwest Gulf waters toward the coast of Mexico.
Current satellite mid-level water vapor shows the high pressure system residing northeast of the Four Corners Region in southwestern Colorado. Monsoonal moisture continues to impact Arizona and New Mexico, while dry air is wrapped around the high into West Texas.
With mid and upper level ridging holding firm to the west of the area over the Four Corners, weak nwrly flow will be in place over the state. Hot and mostly dry conditions are expected to persist through the day Tuesday, with daytime highs a bit warmer across central and northern areas than today.
1012 PM MDT Sun Sep 1 2019 H5 ridge axis continues to build overhead now through tomorrow, keeping skies clear and temperatures well above September normals. Winds will reach 15 to 20 mph for the lower elevations, while higher elevations will see winds of 20 to 30 mph with higher gusts during the afternoon.
Downstream from this feature, a warm front will advance northeast across northwest ND through northeast SD by early evening. A cold front will extend southward from the low through the western Dakotas and advance east during the evening. A moist warm sector will reside south of the warm front. Theta-e advection along a southerly low-level jet will contribute to northeastward destabilization this afternoon and evening with MUCAPE increasing from 2000-3000 J/kg north of the warm front. Given favorable low-level hodographs, a conditional threat will exist for a couple of tornadoes with any surface-based storms that can develop on the warm front. Tuesday will be dry and cooler than Monday after the storms roll through, with forecast highs in the low 60s to low 70s.
The upper ridge axis will nudge eastward throughout the day, leading to weak subsidence. While temperatures will climb into the mid/upper 90s (or even near 100 in Central Texas), dewpoints will mix into the low 60s which will keep heat indices within a degree or two of ambient temperatures.
The primary focus today will be the possibility of severe weather this afternoon and evening in association with a complex theta-e boundary and the associated warm and cold fronts. Showers and thunderstorms continue overnight, mainly east of the Red River as the cold front pushes through the area.
Warm yet tranquil conditions are ongoing across the local area with high pressure aloft stretched across the northern gulf coast. At the surface an inverted trof is moving west across the gulf with the local area being just on the fringes of this feature. High pressure is across much of the southeast states.
A couple days of late Summer heat will return before a modest cold front moves south across the area late Tuesday. A significant upper trof will drop southeast from south central Canada across the Upper Midwest and Great Lakes on Tuesday. The associated surface cold front looks to reach roughly just south of the I-70 corridor by mid-afternoon.
/issued 331 AM CDT Mon Sep 2 2019/ The upper high currently situated over the Four Corners region will work its way eastward by mid week and settle over the FA. While the upper high will be situated nearly overhead into late week there could still be enough moisture available to allow for widely isolated shower/thunderstorm development across the region as possible weak waves rotate around the high. Models diverge heading into the weekend with the evolution of an upper trough across the West Coast.
750 AM MDT Mon Sep 2 2019 Mostly dry and very warm conditions will prevail across much of the forecast area today; but, an isolated shower or two remain possible over the higher peaks of Glacier Park this afternoon. High pressure aloft then builds over the northern Rocky Mountains for continued warm and dry conditions on Tuesday. Today begins under the influence of weak ridging. A trough presses southeastward into our area, weakening the ridge and tightening the height gradient resulting in developing gusty winds. An isolated shower or thunderstorm is possible over the higher peaks of Glacier National Park this afternoon, but mostly dry and warm conditions will prevail across the forecast area today through Tuesday afternoon.
An upper level disturbance and trough will move southeast out of Canada across northeast Montana into north Dakota. This system will sweep a cold front across the forecast area this afternoon into the evening hours. At this time, we are not expecting any thunderstorm activity with the front as most of the energy associated with the trough will be north of our forecast area. Tuesday will see ridging building back over the forecast. However, temperatures will be about 10 degrees cooler in the lower to middle 80s with mostly sunny skies prevailing.
Updated at 252 AM EDT Mon Sep 2 2019 A weak cold front is starting to push into southern Indiana early this morning. Tonight, skies should gradually clear out and winds slacken as high pressures passes by to the north and northeast.