Aikyam-Lab/Synoptic-Bench huggingface dataset:
333 PM EDT Sat Sep 18 2021 Other than an isolated shower or storm today, dry and warm weather is expected through the weekend under a ridge of high pressure. Upper troughing passing through the region, coincident with the passage of a weak cold front, is providing sufficient support for ascent to create isolated showers this afternoon, and perhaps a thunderstorm or two. Patchy fog will once again be possible, particularly in river valleys, as cooler overnight lows are expected as compared to this morning. 5 to 10 degrees cooler in some cases. The forecast area should be situated within broad 850mb high pressure building across the Ohio River Valley. Light, nly flow should help moderate Sunday's high temperature somewhat, but should generally remain above average given rising mid-level heights in response to deepening low pressure near Ark-La-Tex.
With respect to overnight lows, outside of the typically far to warm ECMWF, the consensus of the rest of the models and even MOS range from roughly mid 60s over the lower plains counties (generally east of Dodge) to the the low 60s farther westward to the CO line. Sunday should bring even warmer temperatures by afternoon as the surface-850 mb high over the mississippi valley shifts eastward with a strengthening the lee trough over eastern Colorado, promoting downslope adiabatic warming to the airmass. CAMS indicate quite a bit of confidence in high based thunderstorms , either single cells or clusters by late Sunday afternoon, coming off the higher terrain as an upper level synoptic trough axis approaches the northern Rockies.
Lows fell into the low to mid 40s across much of northern Iowa where calm winds and the driest air was able to filter in behind the surface front yesterday. Moderate WAA related cloud cover over western/northwest Iowa this morning had already dissipated by early afternoon, leaving in its wake generally light southerly to southeasterly winds and overall pleasant temperatures working into the low to mid 80s.
A weak high pressure across the area with weak synoptic flow and abundant tropical moisture.
KY Mesonet obs reveal temps in the low to mid 80s for most, but down across south-central KY, thick cloud cover and recent rainfall has kept temps in the low to mid 70s. Will keep slight chance of PoPs in the forecast through this afternoon and evening as the current weak cold front draped across central IN sags further south this evening.
(This evening through Sunday) Early this afternoon, a mid/upper level high was centered over New Mexico and the adjacent part of northern Mexico, while an upper trough was over the Texas/Louisiana border with an extension southwest along the Texas coast. With moderate instability developing and downdraft CAPE values of 1000-1300 J/kg, localized gusty winds are possible in and near this convection, despite the low coverage. The upper trough over the Texas/Louisiana border will only make slight eastward progress on Sunday, while the ridge to our west weakens but nudges east into Texas. Sunny skies and hot afternoon temperatures are expected for our area, with some strengthening of the 850mb thermal ridge.
Localized cooler temperatures have held closer to the lakes with the northeast flow in place. A 588 ridge will hold over the Great Lakes through the day as surface flow backs to the southeast.
1256 PM CDT Sat Sep 18 2021 Weak ridging aloft will develop over most of the area today with temperatures remaining well above mid-September climo. Similar scenario on Sunday though a bit warmer with stronger south winds across central Kansas as lee side trof deepens over the high Plains.
High moisture levels will continue with a weak mid/upper low slowly moving NE tonight and tomorrow, but still providing some lift to aid shower and thunderstorm development. Max temps should range from the lower 90s west to upper 80s east and coastal areas tomorrow.
Primary forecast concerns are going to be focused on winds with the trough, temperatures and associated fire weather risks. A few locations, especially on local ridges may stay quite warm tonight as winds never get a chance to decouple tonight. With temperatures starting warmer on Sunday than today and a decent amount of sunshine expect temperatures to respond by climbing into the 90s. Cold front will sweep across the area overnight Sunday, likely in the 06-12Z period. At the start of the period, an upper trough can be seen entering the northern and central Plains, placing the region under southwest flow. Meanwhile at the surface, a cold front is pushing through the region.
142 PM EDT Sat Sep 18 2021 Upper air pattern consists of a 500 mb ridge across the southern plains into the sern U. The ridge amplifies into the upper Great Lakes tonight as an amplifying trough moves into the western U.
250 PM EDT Sat Sep 18 2021 As advertised, a broken cloud line quickly developed along portions of the Lower and Middle Keys, resulting in at least one waterspout near Marathon. A ridge will continue to build across the Florida Keys through Sunday. The ridge axis is then expected to lift northward Sunday night, resulting in freshening moist easterlies.
233 PM EDT Sat Sep 18 2021 There may be a shower or thunderstorm in spots today as a weak cold front pushes through later in the day, but most of the time will be dry.
216 PM EDT Sat Sep 18 2021 High pressure will build across the region tonight into Sunday, leading to mainly dry and continued warm conditions.
A weak vort lobe on the east side of a weak upper level trough in the Gulf of Mexico was bringing scattered showers into our western coastal waters. The first batch of showers dissipated as they moved east of the warmer loop current but the next batch looks like it could reach land. A weak trough of low pressure across the waters gradually fills as high pressure builds in during the weekend then resides in place for early to mid week.
Sctd TSRA will develop again with the highest confidence remaining over central/southern terminals.
810 PM EDT Sat Sep 18 2021 Dry and warm weather is expected through the weekend under a ridge of high pressure. Cooler air will settle into the region behind a cold front. Overnight lows are expected to be cooler as compared to this morning. 5 to 10 degrees cooler in some cases. The forecast area should be situated within broad 850mb high pressure building across the Ohio River Valley. Light, nly flow should help moderate Sunday's high temperature somewhat, but should generally remain above average given rising mid-level heights in response to deepening low pressure near Ark-La-Tex.
725 PM EDT Sat Sep 18 2021 VFR conditions through the taf period as an area of high pressure slides east across northern Michigan. Localized cooler temperatures have held closer to the lakes with the northeast flow in place. A 588 ridge will hold over the Great Lakes through the day as surface flow backs to the southeast.
638 PM CDT Sat Sep 18 2021 For the 00Z TAFs, winds will diminish early this evening, then increase and become gusty by late Sunday morning, continuing through the afternoon hours as the pressure gradient tightens in response to a developing surface trof of low pressure over eastern CO and ern NM. Tomorrow's highs will range from the low to upper 90s. Normal highs this time of year are in the low to mid 80s. Further Details: High pressure aloft will be in place through today and tonight. By tomorrow, an approaching trough from the west will flatten this high out and turn our flow more zonal at 500mb. There is also a lot of dry air in the low to mid levels, which is very noticeable in the inverted-v forecast soundings.
Aloft, a broad upper ridge extended across the central and eastern Gulf of Mexico. 0 inch values from the KEY sounding match well with a dry area from the Lower Keys through the western Straits. The higher values to our north were likely modified by the convective debris cloudiness aloft. Continuing from the earlier synopsis, a ridge will build westward across the Florida Peninsula overnight,bringing gentle easterly breezes by Sunday.
252 PM PDT Sat Sep 18 2021 Cooler and breezy through Sunday as weather system moves through North California. The onshore flow has resulted in cooler temperatures across the Central CA Interior. Winds should strengthen tonight as a cold front approaches the area leading to critical fire weather conditions in the southern sierra and Tehachapi Mountains tonight and Sunday.
745 PM EDT Sat Sep 18 2021 A weak cold front push south into Virginia tonight then wash out across the the area Sunday.
It will continue to be breezy to locally windy as a Pacific cold front approaches the area.
759 PM EDT Sat Sep 18 2021 A weak cold front push south into Virginia tonight then wash out across the the area Sunday.
Upper level trough axis in place with plentiful moisture and a myriad of outflow boundaries from previous convection will be the ingredients necessary for any additional isolated convection overnight.
/28/ Through Sunday: A persistent mid level low circulation centered west of the lower MS River valley will continue to pull very moist air (precipitable water > 2 inches) northward through much of the ArkLaMiss region.
703 PM EDT Sat Sep 18 2021 Other than an isolated shower or storm today, dry and warm weather is expected through the weekend under a ridge of high pressure. Upper troughing passing through the region, coincident with the passage of a weak cold front, is providing sufficient support for ascent to create isolated showers this afternoon, and perhaps a thunderstorm or two. Patchy fog will once again be possible, particularly in river valleys, as cooler overnight lows are expected as compared to this morning. 5 to 10 degrees cooler in some cases. The forecast area should be situated within broad 850mb high pressure building across the Ohio River Valley. Light, nly flow should help moderate Sunday's high temperature somewhat, but should generally remain above average given rising mid-level heights in response to deepening low pressure near Ark-La-Tex.
931 PM EDT Sat Sep 18 2021 There may be a shower or thunderstorm in spots this evening as a weak cold front pushes through, but most of the time will be dry.
716 PM EDT Sat Sep 18 2021 High pressure is dead overhead this afternoon, providing very quiet wx. That will continue tonight, even as the high heads east and we get the first inklings of low-level return flow.
813 PM EDT Sat Sep 18 2021 High pressure will build across the region tonight into Sunday, leading to mainly dry and continued warm conditions.
/issued 250 PM CDT Sat Sep 18 2021/ SHORT TERM (Tonight through Sunday Night): As the 500mb trough moves eastward out of Deep South Texas, the rain chances have decreased for the CWA for most of the period.
Cooler and breezy through Sunday as weather system moves through North California. The onshore flow has resulted in cooler temperatures across the Central CA Interior. Winds should strengthen tonight as a cold front approaches the area leading to critical fire weather conditions in the southern sierra and Tehachapi Mountains tonight and Sunday.
It should be a quiet and mainly cloud free night across the region with overnight lows dropping into the lower 70s. Our slow moving upper low just to our east will continue to slowly move east through the day Sunday.
1052 PM EDT Sat Sep 18 2021 High pressure will build across the region tonight into Sunday, leading to mainly dry and continued warm conditions.
High resolution guidance indicates the development of scattered/isolated SHRA beginning a few hours earlier this morning as an upper level trough continues to slowly push out of the area. High moisture levels will continue with a weak mid/upper low slowly moving NE tonight and tomorrow, but still providing some lift to aid shower and thunderstorm development. Max temps should range from the lower 90s west to upper 80s east and coastal areas tomorrow.
524 PM MDT Sat Sep 18 2021 Water vapor shows the upper ridge shifting eastward, as an upper trough moves inland over the Pacific Northwest. Another warm, dry, and breezy to windy day expected on Sunday ahead of cold front associated with the upper trough crossing the Northern Rockies. A cold front will enter northeastern Wyoming and far northwestern South Dakota late Sunday afternoon, speeding across much of the rest of the forecast area in the evening. Pressure rises behind the cold front, in excess of 6mb/3hr, will lead to 2-3 hour period of very gusty northwest winds in the evening hours.
611 PM CDT Sat Sep 18 2021 Temperatures are beginning to exceed expectations early this afternoon with readings in the low 70s in northwest WI to as high as the upper 70s over southwest MN. A deep trough over the Pacific Northwest and healthy ridging centered over the lower Mississippi Valley have resulted in near meridional flow over the Rockies today. This fast southerly flow will spread eastward through the period with the advancing trough and will eventually tap into deeper moisture Sunday night. Very strong moisture transport on a 50 kt LLJ will facilitate shower and thunderstorm development along and behind the cold front late Sunday night.
710 PM EDT Sat Sep 18 2021 There may be a shower or thunderstorm in spots this evening as a weak cold front pushes through, but most of the time will be dry.
732 PM EDT Sat Sep 18 2021 There may be a shower or thunderstorm in spots this evening as a weak cold front pushes through, but most of the time will be dry.
5"), and a subtle low level trough across SE OK, expect this activity to persist for another hour or two before gradually diminishing.
849 PM EDT Sat Sep 18 2021 A cold front will cross the area late tonight.
330 AM CDT Sun Sep 19 2021 (Issued 330 AM CDT Sun Sep 19 2021) Today: High pressure over the eastern Great Lakes will continue to slowly push eastward throughout the day. This will allow southerly winds to develop and bring with it a much warmer air mass. Areas along Lake Michigan will be cooler in the 70s to low 80s.
313 AM CDT Sun Sep 19 2021 The heat beat will continue today with temperatures a degree or two warmer than yesterday. South winds will also ramp up a bit more in the afternoon across central Kansas in response to the deepening lee side trof over the high Plains.
210 AM CDT Sun Sep 19 2021 Upper level ridge will be flattened today as a large trough works across the Great Basin. This will lead to warmer temperatures across the region with most locations in the mid to upper 90's.
ABM Chattanooga Airport, TN 79 69 78 69 80 / 80 70 70 50 80 Knoxville McGhee Tyson Airport, TN 84 68 80 68 80 / 40 50 50 40 70 Oak Ridge, TN 82 68 79 67 79 / 60 50 60 40 70 Tri Cities Airport, TN 86 67 79 65 79 / 20 20 40 30 60.
(This afternoon through Sunday night) An upper ridge is building over West Texas and Southeast New Mexico. The upper ridge gets suppressed a bit on Sunday as a broad upper trough moves over the northern Rocky Mountains and Pacific Northwest.
332 AM EDT Sun Sep 19 2021 A cold front will drop southward today as high pressure to our north settles over New England.
1055 PM MDT Sat Sep 18 2021 Water vapor shows the upper ridge shifting eastward, as an upper trough moves inland over the Pacific Northwest. Another warm, dry, and breezy to windy day expected on Sunday ahead of cold front associated with the upper trough crossing the Northern Rockies. A cold front will enter northeastern Wyoming and far northwestern South Dakota late Sunday afternoon, speeding across much of the rest of the forecast area in the evening. Pressure rises behind the cold front, in excess of 6mb/3hr, will lead to 2-3 hour period of very gusty northwest winds in the evening hours.
Lee troughing will continue to strengthen today as a strong upper level trough digs into the Intermountain West. As for temperatures, highs this afternoon will reach into the low 90s with lows tonight ranging from around 60 degrees along the KS/CO border to around 70s degrees across south central Kansas.
The cold front should be generally east of the forecast area this evening. Rain continues to fill in, with radar indicating increased coverage of precipitation over the higher elevations.
With a southeasterly 850mb jet progged to increase up to 30 knots today oriented perpendicular to the inverted trough, strong convergence along with the highly moist troposphere spells another round of heavy rain and potential flash flooding this morning into the afternoon, before activity diminishes by the evening. Highest threat area for flash flooding today looks to be on the southeast side of the inverted trough axis across our south-central and southeast counties, most of which received 2 to 6 inches of rain yesterday.
Warm front produced virga over the area this afternoon and evening, but lower levels just to dry to have much of anything reach surface. Cold front has moved through front range of Montana and is headed our way. Along with that, temperatures are running 15 to 20 degrees warmer than yesterday. Models are still showing the cold front moving through the area overnight tonight, with the front likely through the area by sunrise tomorrow.
/28/ Prior discussion below: Through Sunday: A persistent mid level low circulation centered west of the lower MS River valley will continue to pull very moist air (precipitable water > 2 inches) northward through much of the ArkLaMiss region.
1045 PM CDT Sat Sep 18 2021 Temperatures are beginning to exceed expectations early this afternoon with readings in the low 70s in northwest WI to as high as the upper 70s over southwest MN. A deep trough over the Pacific Northwest and healthy ridging centered over the lower Mississippi Valley have resulted in near meridional flow over the Rockies today. This fast southerly flow will spread eastward through the period with the advancing trough and will eventually tap into deeper moisture Sunday night. Very strong moisture transport on a 50 kt LLJ will facilitate shower and thunderstorm development along and behind the cold front late Sunday night.
An associated surface cold front currently extends south/southwest from low pressure over south-central Canada into the High Plains region.
A large ridge has moved off into the Dakotas followed by a cold front moving through the area early this morning. Behind it a large trough resides over the Pacific Northwest and British Columbia. Farther west another ridge is forming up over the Gulf of Alaska dropping south.
1143 PM EDT Sat Sep 18 2021 Abundant dry air associated with strong high pressure across the eastern Great Lakes will maintain clear skies into Sunday evening. Localized cooler temperatures have held closer to the lakes with the northeast flow in place. A 588 ridge will hold over the Great Lakes through the day as surface flow backs to the southeast.
401 AM EDT Sun Sep 19 2021 Upper air pattern consists of a 500 mb trough in the Pacific NW and a ridge on the Gulf Coast up into the upper Great Lakes. The trough moves into the Rockies 00z Mon and starts to move into the northern plains 12z Mon.
(Today and tonight) Hot and dry conditiions are forecast across West Central Texas today, as an upper level ridge dominates the weather across the region. (Sunday night through next Saturday) Upper level trough will move into the northern Rockies to start the week off, allowing a better cold front to develop and move south towards West Central Texas.
334 AM EDT Sun Sep 19 2021 High pressure in Quebec will settle into Maine tonight.
456 AM EDT Sun Sep 19 2021 A trough lingers across the area this morning, gradually dissipating as weak high pressure builds in at the surface and aloft.
A cold front will push across the region today, bringing showers across the north, much cooler temperatures and windy conditions.
(Today and tonight) Hot and dry conditiions are forecast across West Central Texas today, as an upper level ridge dominates the weather across the region.
The trough will bring the initial frontal surge into the NW Parks tomorrow morning, with temperatures there stalling in the 40s and low 50s through the day.
154 AM EDT Sun Sep 19 2021 High pressure will build across the region tonight into Sunday, leading to mainly dry and continued warm conditions.
232 AM MDT Sun Sep 19 2021 Water vapor shows upper trof building from the Pac NW into the Northern Rockies. At the surface, low center is over northwest ND with trof extending southward through the NEB panhandle. Warm and windy conditions will prevail again today with surface trof advancing slowly eastward across the Dakotas. Near critical fire weather conditions will be the main concern for today ahead of an approaching cold front. The cold front will sweep through northeast WY and far northwest SD late this afternoon, then advance through the rest of western SD this evening.
There were a couple of isolated showers that develop, one over the Florida Bay, and another over portions of the lower Keys. The north to northeast steering flow aloft is thanks to a low and mid level ridge situated across the eastern Gulf of Mexico. As we go through the day today, the low and mid levels should further moisten up. As we start the new work week, deep layer ridging will push further west.
Although this low-level jet will be quite veered (wind direction from 220-250 degrees) and not be advecting a plume of moisture as we often see with the more typical southerly low-level jets, the jet tonight does look to interact with a relatively narrow north-south axis of somewhat deeper moisture and helps produce a component of isentropic lift late tonight with this moisture axis.
Higher gusts near 60 MPH will be off and on through the morning as waves break, but in general we would expect this to persist as model x-sections suggest a strengthening stable layer at 600-700 hpa through around 15z which could help to support continued mountain wave development despite decreasing low level gradients with the eventual cold frontal passage. In-house wind guidance continues to suggest winds remaining elevated at ARL through late this evening, so we did opt to keep the High Wind Warning going through 03z. Main cold frontal surge occurs this evening and overnight with the potential for scattered to numerous rain and mountain snow showers across much of the area. An inch or two of snow accumulation could occur on the high peaks of the Snowy range through early Monday AM w/ a general light dusting possible above 7500 feet.
1030 AM EDT Sun Sep 19 2021 High pressure builds in today Sunday and holds over the area through midweek with fair weather and above normal temperatures.
1019 AM EDT Sun Sep 19 2021 Surface analysis depicts a split ridge pattern. The ridge associated with the Bermuda High is cut off on its westward extent by what is now Post- tropical Cyclone Odette, as another high pressure centered over Canada gradually strengthens and shifts eastward. From synopsis, a ridge will continue to build westward across the Florida Peninsula this afternoon, bringing gentle northeast to east breezes.
South-southwest flow aloft this morning with the area still between upper high near El Paso and upper level trof to our west. As the upper level trof to our west pushes across the state, drier air will move in.
500 hpa hghts over the forecast area will be lower today than previous days, however southerly return flow and the expansion of the low lvl thermal ridge will promote warmer highs this afternoon. The heat is expected to really crank up on Monday as a large upper trof enters the Central Plains. This trof will promote westerly downsloping winds across West Texas and southeast New Mexico, yielding highs 13F-15F above normal.
Tomorrow into early Monday an open trough is expected to develop just west of the Mississippi River resulting in slightly better steering flow across the Midsouth.
- Strong cold front moves through Monday mid afternoon into Monday evening.
An associated surface cold front currently extends south/southwest from low pressure over south-central Canada into the High Plains region. Current timing on the cold front brings it into far northeast Nebraska Monday 08-10z and through the entire CWA by Monday 18-20z.
946 AM EDT Sun Sep 19 2021 High pressure in Quebec will settle into Maine tonight.
Daytime temperatures will be cooler than the seasonal average today and Monday.