Aikyam-Lab/Synoptic-Bench huggingface dataset:
Upper level trough will continue to move across the region overnight into Thursday. The trough axis will be over the forecast area Thursday afternoon and may generate scattered showers over northeast Oregon. Cooler temperatures with highs in the 60s and 70s. Upper level ridge builds into the area Friday with a dry northerly flow and sunny skies.
Ridge of high pressure will build over along the Eastern Seaboard creating a weak onshore flow through the weekend.
Will keep in the mention of thunder in the PA ridge counties as enhance low-level moisture convergence is prompting the development of convection. Upper low will slowly move eastward, reaching Western PA by early afternoon. While the bulk of the precipitation should end by midday, low clouds, and ridge county showers will likely continue the rest of the day.
Upper low in southern California continues to weaken and lift as a sharp upper trough approaches the PAC NW. The surface cold front associated with the PAC NW trough will pass into our western zones around 6 to 9 pm this evening. Models are pushing in some much cooler temps behind the front, with snow levels dropping below 10,000 ft tonight across much of the area.
Unsettled weather will last through Friday as weak low pressure remains over the northeast United States. This first precipitation was associated with some modest destabilization as cooler air advects in aloft in the presence of the maximum diurnal heating. This activity was associated with lifting from the approaching upper level low over the Ohio Valley. Hence we don't expect anything but a few showers overnight into Thursday as the weak upper level low moves right into central NY. With cooler air aloft, we expect some instability and even a few rumbles of thunder.
The higher moisture will generate humid, muggy and generally uncomfortable weather across South Florida, while pushing dew points into the mid-upper 70s.
As remnants of Irma push eastward out of the US upper level ridging will build back over South Texas. Dewpoints are back into the lower to mid 70s through the eastern half of the forecast area. High temperatures today back around or a bit warmer than yesterday.
The lowest ~10,000ft of the air mass is quite dry so rainfalls should be minimal. Tonight: With a more assertive southerly flow lows would likewise be warmer than the past 3 or nights. upper-deck wave & its attendant cold front. With broad & STRONG mid-upper deck ridging nearly covering the southeastern half of the U. This would cause the attendant SE-moving cold front to move further into Nebraska & Northwest KS late Fri night & Sat.
541 AM CDT Thu Sep 14 2017 Light and variable to calm winds dominated Central IL this morning under a weak high pressure ridge axis. The western ridge drifts east somewhat, warming the midlevels a couple of degrees to 17-19C at 850mb.
Mid level troughing will linger over the region today while surface ridging noses across the southeast states from the east. Just east of the mid level trough axis, across our southeast zones, PWATs will remain above an inch and a half. Temperatures will top out closer to normal but, will still be a couple degrees cooler than normal at most locations. Cooler than normal temperatures will continue tonight but the warming trend started today will continue into Friday.
Weak high pressure will hold across the area tonight into the weekend with Jose well off the coast. Weak high pressure will be over the area today.
256 AM EDT Thu Sep 14 2017 High pressure now over the region will give way to increasing moisture and a weak low pressure system associated with the remnants of Irma through Friday. High pressure will build into the region for the coming weekend. A strong short wave impulse will become negatively tilted as it ejects ENE late in the weekend, serving to slightly flatten the top of ridging over New England. The northern stream ridge will build a bit more as the short wave moves into northern Canada. Late in the week sharp ridging will dominate the eastern CONUS as Jose moves farther out to sea.
239 AM CDT Thu Sep 14 2017 Latest water vapor satellite imagery indicates upper level trough over the Pacific Northwest/British Columbia/Alberta Canada and upper level ridge over the central High Plains. Latest 07z surface analysis shows ridge over the Ohio River valley and latest metars indicated patchy dense fog over the favored areas of central Wisconsin and the Wisconsin River valley. Upper level ridge begins to amplify over the central United States today and allows warmer air aloft to advect into the forecast area.
Temps and dew points this afternoon have risen into the low 80s and low to mid 60s, respectively. The extended periods continue to feature a broad ridge across the eastern CONUS, only making some minor fluctuations over the next several days. Thur will feature a weak series of low pressure systems traversing the Missouri Valley, and eventually lifting north across the Upper Peninsula. But confidence remains low given the possible lingering ridge aloft and trough developing across the western CONUS. VFR conditions and winds mostly under 10 knots will continue under surface ridging, although shallow fog should develop at KSAW early this morning. Then, a warm front associated with low pressure over the mid-Mississippi Valley will settle over western Lake Superior, bringing NE winds to 25 knots Friday into Friday night.
Models continue to show weak high pressure over the region, with mainly isolated to scattered diurnal convection through the period.
232 AM CDT Thu Sep 14 2017 Upper level ridge of high pressure over the Panhandles will get displaced to the south and east today. The showers and thunderstorms may have a chance to move all the way across the Panhandles tonight as an upper level short wave trough in the southwest flow aloft helps to keep the activity going through the night. A southwest flow aloft will prevail across the Panhandles through the rest of the forecast as a large trough develops over the western U. This trough is expected to be a focus for shower and thunderstorm development in the afternoon and evening.
VFR conditions will continue through the next 24 hours with high pressure in control. /issued 241 PM CDT Wed Sep 13 2017/ SHORT TERM (Tonight through Thursday Night): Deep South Texas and the Rio Grande Valley will be positioned between 500 mb high pressure that will ease east from northwest Mexico to the north- central part of the country, and 500 mb low pressure (the remnants of Irma) that will gradually move from the Ohio River Valley to New England. After several days of refreshing temperatures in the wake of an early cold front, temperatures will return to well above normal levels courtesy of the limited cloud cover and decreasing precipitable water values.
Broad low pressure system as the remnants of Irma continue to bring cloud cover and light to moderate rains to the region this afternoon. Friday morning we will start to see ridging become more dominant aloft and surface winds become more south and southeasterly, which will start a warming trend. As for our next rain chances, models continue to try and handle a weakness moving over the top of the ridge Sun.
A sharp upper level trough is driving a cold front inland this morning. However, given the very dry subcloud layer of the atmosphere, confidence is not very high on any place receiving measurable precipitation except perhaps the higher elevations of the Cascades.
The upper level ridge axis currently extending from southern NM into southeastern CO will shift east into our CWA today, as an upper level low and associated trough axis move northeast near the four corners region. With the ridge axis moving into our area, continued sinking, drying air, along with mainly sunny skies will result in another hot day, with near record temperatures at Abilene and San Angelo. Although the GFS shows a few isolated showers along our western/northwestern counties by late afternoon, think the sinking air within the ridge will suppress convection enough to keep any showers from affecting our area.
Issued by National Weather Service AUSTIN/SAN ANTONIO TX 449 AM EDT Thu Sep 14 2017 Isolated showers and an occasional thunderstorm continue across the area with a few of the showers passing through mainly the lower keys. Temperatures are currently in the lower 80s across the region. The Florida Keys remain under the influence of high pressure that is primarily centered to the east with troughing across the north-central Gulf of Mexico. Lows tonight will bottom out in the lower 80s once again with a slightly lower chance of showers and storms than today. For tomorrow, the ridge is expected to be stronger and centered just to the east. Think this will allow there to only be enough to warrant a 20 PoP for the western half of the area where the effects will of the ridge will be less.
South southwesterly flow continues due to location of the low as it pushes eastward. A deformation axis on the northeastern edge of the low will encourage some shower development across the higher terrain of the Dacks by mid morning, then additional development eastward across Vermont during the afternoon. Drying trend expected for the short term as high pressure ridging builds into the region. Some residual showers possible early Friday night as 500mb trough shifts east of the North Country. Expect mostly clear to partly cloudy skies with drier air in place with building ridge.
While there'll be some broad synoptic forcing across the region, the highest PoPs will be along the seabreeze in the Big Bend, moving into south- central Georgia.
Scattered showers and storms remain possible across much of the region this morning before a strong trough pushes moisture eastward tonight. The weather will be cooler than recently experienced over the weekend with temperatures several degrees below normal.
The occluded low over the Tennessee Valley will lift northeastward today, with a weak, broad upper low lingering west of the area. POPs will generally range between 30 and 40% in this area, with the highest chances in the eastern Big Bend region.
South southwesterly flow continues due to location of the low as it pushes eastward. A deformation axis on the northeastern edge of the low will encourage some shower development across the higher terrain of the Dacks by mid morning, then additional development eastward across Vermont during the afternoon.
339 AM CDT Thu Sep 14 2017 Latest water vapor imagery shows an upper low/trough continuing to develop/sharpen up as it is forecast to migrate into the northern rockies tonight. As the upper low and associated trough edge closer tonight, widespread rainshowers will commence in the west as synoptic scale ascent increases, and overlaps with low level frontogenetical forcing per NAM/GFS QG.
343 AM CDT Thu Sep 14 2017 Latest water vapor imagery shows an upper low/trough in the Pacific northwest, continuing to develop/sharpen up, as it is forecast to migrate into the northern rockies tonight. As the upper low and associated trough edge closer tonight, widespread rainshowers will commence in the west as synoptic scale ascent increases, and overlaps with low level frontogenetical forcing per NAM/GFS QG.
The upper low that was off the California coast over the past two days has moved inland and will continue to move ENE today across southern NV, southern UT and northern AZ. Cooler with highs a few degrees above normal. Gusty SW winds to continue on Friday as another upper level trof passes by to our north.
There are a few light sprinkles in the area associated with the weakening trough.
A wave of low pressure is moving northeast along the front early this morning with upper level support as well.
Temperatures will remain well above normal in advance of a developing large-scale western trough through Friday with isolated thunderstorms possible again tonight as mid-level warm advection moves across the region. Low-level moisture will increase across the Central Plains Friday ahead of advancing western trough. A lee cyclone is forecast to develop across western Kansas while a secondary low forms across eastern South Dakota.
646 AM EDT Thu Sep 14 2017 High pressure now over the region will give way to increasing moisture and a weak low pressure system associated with the remnants of Irma through Friday. High pressure will build into the region for the coming weekend. A strong short wave impulse will become negatively tilted as it ejects ENE late in the weekend, serving to slightly flatten the top of ridging over New England. The northern stream ridge will build a bit more as the short wave moves into northern Canada. Late in the week sharp ridging will dominate the eastern CONUS as Jose moves farther out to sea.
Today Through Friday Night Water vapor satellite imagery this morning shows the remnant upper low associated with Irma pushing northeastward through the Ohio river valley. Over the southern Rockies and into west Texas evidence of upper level ridging can be seen, while another upper low shifts east through southern California. Upper ridging will begin to shift east through Texas and the southern plains today as the aforementioned southern Cal low moves northeast into Utah and Colorado. Lastly, the forecast will be a dry one with the upper ridge overhead.
Unsettled weather will last through Friday as weak low pressure remains over the northeast. Upper level low over Ohio will lift northeast as it weakens and move into New York and Pennsylvania. Highs will be in the lower to middle 70s.
606 AM EDT Thu Sep 14 2017 A weak cold front will move across the north today and stall.
Tonight Through Friday Well, the cooler weather was nice while it lasted. Through the remainder of the week, upper ridging will build back into the area.
257 AM EDT Thu Sep 14 2017 Early this morning, light rain showers and patches of drizzle continue on the back side of a departing upper low. In places where there are breaks in the low cloud deck, some of the fog could become patchy dense fog. High temps should rebound into the low to mid 70s today.
401 AM EDT Thu Sep 14 2017 Latest surface analysis shows high pressure sitting stagnant over the southeast CONUS.
624 AM EDT Thu Sep 14 2017 Update Areas of dense fog will lift this morning and high pressure will bring fair weather through the end of the week.
Upper level trough will push into the region today, bringing cooler air and isolated to scattered rain showers to the area. Temperatures Friday night will be warmer than guidance as a moderate west to northwest keeps the atmosphere well mixed. Showers will taper off in SE Oregon early Friday morning, but wrap around moisture associated the the low pressure will continue in the Idaho zones, especially focused on the central Idaho mountains on Friday.
229 AM MDT Thu Sep 14 2017 Omega block will remain in place across the CONUS over the next few days, with ridge extending north across the High Plains through Thursday. Near record high temperatures will be possible again Thursday, with highs nearing 100F at warmer locations. Pulses of disorganized vorticity are rotating around the ridge from the Central Rockies into our CWA will allow for elevated showers or thunderstorms to develop. Predominantly southwesterly flow will continue in the upper levels due to a strong ridge to the south-southeast and a longwave trough to the north-northwest of our region. The longwave trough looks to move east across the Northern U.
Highs should range from the upper 60s to middle 70s across northern Minnesota, to the lower 80s across northwest Wisconsin into central Minnesota.
338 AM CDT Thu Sep 14 2017 A warming will get underway today as skies clear slowly from west to east as low pressure finally lifts northeast out of the region. Light southwest winds and a return to some sunshine should help most locations breaK back into the lower half of the 80s.
321 AM MDT Thu Sep 14 2017 Latest upper level analysis shows an upper trough swinging across southwestern Canada and into the northwestern CONUS which is turning the upper flow over the forecast area from zonal to southwesterly. At the surface, low pressure is centered over South Dakota. Beginning today and continuing into the weekend, moist and cooler air will move into the region as the upper trough approaches and swings across the northern plains.
1244 AM CDT Thu Sep 14 2017 VFR and dry with upper level high pressure ridge passing overhead this afternoon. /issued 331 PM CDT Wed Sep 13 2017/ The area will remain under the upper ridge for the next few days as the axis slides east. As the ridge moves further east on Friday highs will be slightly lower in the low to mid 90s. The upper low over California will open as it moves east through the weekend. Moisture with the associated trough may reach the northwest part of the CWA so included a slight chance of thunderstorms for the weekend.
In it's wake, a weak upper trough is presently situated over the northern gulf coast where it is expected to remain over the next couple of days. With plenty dry air in the low and mid levels of the atmosphere, the trough will have little material impact on today's weather. By Friday, mid level winds turn southerly in response to ridging across the northeastern gulf at around 700 MB.
Upper low will slowly move eastward, reaching Western PA by early afternoon. While the bulk of the precipitation should end by midday, low clouds, and ridge and northeast county showers will likely continue the rest of the day.
1116 PM MDT Wed Sep 13 2017 Upper level analysis shows upstream trof over western Canada, an upper low off the southern California coast, and weak ridging over the northern high plains. Water vapor imagery shows ample high and mid level moisture streaming into the Pacific Northwest and Upper Rockies associated with and ahead of the approaching upper level trof. At the surface, a weak frontal boundary extends from northern Minnesota through northern South Dakota into southeastern Montana, with a more pronounced cold front extending from southeastern Saskatchewan through central and southwestern Montana. Beginning tonight and continuing into the weekend, moist and colder air will move into the region as the upper trof approaches and swings through the northern plains.
Upper trof over western Canada will be digging south into the northern Rockies over the next few days. Cold air filtering south of the border from high over Alberta, with Pacific moisture in the southwest flow ahead of the trof overrunning this cooler airmass and producing scattered showers this morning. Widespread rain shield expected to develop around this low as it moves east across Wyoming tonight and Friday.
High pressure will build across the region on Friday, extending across the Great Lakes and Ohio Valley for much of the weekend. The high will bring warmer temperatures back to the area. Mid level closed low across the middle Ohio Valley this morning will slowly rotate east into central Pennsylvania by this evening. Highs will be tempered by clouds, ranging from the upper 60s to the lower 70s. On Friday, mid level ridging will occur as surface ridging remains just off to our east.
The clouds may be lifting by tomorrow morning, but the short-range models are not totally sold on an end to the chance of rain, since shallow low-level moisture will linger well behind the primary trough axis. Likewise, the low-level moisture will keep at least partly-mostly cloudy conditions in the sky cover until late Thursday afternoon. The weekend will almost feel hot relative to the cooler temps the TN Valley has been experiencing recently.
The onshore flow will usher slightly warmer temps increasing moisture back across S TX on Mon. The upper level jet on the back side of a trough progged to move across TX on Mon will be in a favorable position by Mon afternoon for upper level support of a few -SHRAs.
Widespread fog and freezing fog has developed in west side valleys, with some reports of visibility less than a quarter mile. Tonight, an upper trough front will start approaching, and on the front side of the trough, a stream of moisture with tropical origins will bring heavy precipitation as early as this evening. Low temperatures east of the Cascades will be near freezing tonight, cloud cover ahead of the system should prevent temperatures dropping to below freezing. Thus, freezing rain is not considered a threat on the East Side, at this time, though we will continue to monitor the potential.
Snow showers will continue across the higher elevations today with clearing skies elsewhere. Chattanooga Airport, TN 50 29 56 37 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 47 27 54 36 / 0 0 0 0 Oak Ridge, TN 47 27 54 36 / 0 0 0 0 Tri Cities Airport, TN 43 25 51 28 / 10 0 0 0.
A weak front has brought somewhat cooler conditions to the area, though unseasonable warmth will quickly return this week. Instead a northwesterly flow around a building ridge in the eastern Pacific will reinforce the dry airmass and mostly clear skies.
The pattern aloft depicts northwest flow across the Central Plains with weak upper ridging along the west coast and Rockies. At the surface, high pressure was located in the southern plains and in a dry airmass, early morning temperatures were rather chilly in the 20s.
Northwest winds are expected to gust to around 20 knots today across most of the area behind a cold front, diminishing around sunset. By sunrise, the cold front will have moved through most of the area with a thin line of showers confined to the southeast big bend. These will exit the area quickly this morning with clearing skies, breezy northwest winds, and a cooler airmass behind the front.
This will result in a strong ridge building from Baja California north thru the Intermountain West and into British Columbia/Alberta. A weak cold front will clip the CWA with little effect midweek. The large ridge in the west will build east into the Southern Plains for the Thanksgiving Holiday weekend.
Today will bring generally light valley winds (with some southwest to west winds for ridges) and seasonable afternoon temperatures under modest ridging aloft.
442 AM MST Sun Nov 19 2017 Water vapor shows upper ridge over the western CONUS with NW flow across the Northern Plains. Broad trof at the surface over the Northern Plains with dry w/sw flow. Persistent upper ridge over the western CONUS expected through the week, bringing mainly dry and mild conditions to the region. One exception to this will be a clipper system that drives a cold front through the cwfa late Monday.
Monday will feature a taste of early fall weather with temperatures 10 to 20 degrees warmer than normal. West to southwest winds will bring warmer air ahead of a dry cold front. The dry cold front will drop south across the area Monday evening into the overnight hours, resulting in a big change in temperatures. Cooler air builds in behind the front keeping highs in the 20s and 30s.
305 AM MST Sun Nov 19 2017 High pressure aloft along with occasional westerly winds will bring dry mostly sunny weather with warming temperatures this week. light winds and low humidity will allow low temperatures to fall below freezing over much of the lower elevations.
Warmer air will move into central into SE ND this aftn but light east wind will keep NE ND into NW MN on the cold side. Warm advection in the low levels will kick in later tonight as winds turn southerly. A system supported by an upper level trough will bring the chance for some precipitation on Monday afternoon through Monday night. With the warmer temperatures on Monday precipitation would likely start as rain before transitioning to snow.
High pressure will continue to build into the region. Winds should drop off all areas this afternoon as high pressure continues to build in. /issued 355 AM CST Sun Nov 19 2017/ Sfc observations currently show the cold front which passed the forecast area last evening has now moved off the sern LA coastline and lies well beyond the marine zones this morning. Main story into tomorrow will again be the much cooler temperatures as highs each day are expected to top out in the lower/mid 60s (as opposed to our recent maxes around 80).