Aikyam-Lab/Synoptic-Bench huggingface dataset:
Water vapor imagery shows cyclonic flow across California spreading east to the Northern and Central Plains with an amplified trough moving onshore the West Coast. Highs will be similar to a few degrees cooler than yesterday with values 14-18 degrees above seasonal normal values â largely mid-upper 70s. Large scale trough moves east to the Northern Rockies to Central Great Basin-Central Rockies today. Mean mixed-layer winds of 25+ kts covering an appreciable portion of the forecast area outside the aforementioned areas near the trough. Overnight, a surface cold front will advance east across the area mid-late evening through early morning tomorrow. More wind expected Saturday in the wake of the cold front. Drier air in place, along with the clear calm conditions will allow for a chilly night as lows drop into the lower 30s.
Chattanooga Airport, TN 78 50 76 56 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 77 48 76 52 / 0 0 0 0 Oak Ridge, TN 78 49 77 52 / 0 0 0 0 Tri Cities Airport, TN 78 45 76 48 / 0 0 0 0.
Upper air analysis last evening showed a negatively tilted trough extending from Utah to South Texas. At the surface, high pressure was centered to the northeast and winds across our CWA were from the east to southeast. During this period the upper trough will be reinforced by another trough moving down from the northwest. The low level flow will remain from the southeast and this combination will produce a chance for showers and thunderstorms over the eastern half of our area.
High pressure will continue to provide dry weather through the first part of the weekend.
1057 AM EDT Fri Oct 20 2017 A weak and dry cold front will continue to traverse the North Country through the overnight hours. Behind the front temperatures will be slightly cooler but high pressure quickly builds back in.
Strong southerlies will reinforce a warmer air mass already in place across the high plains today with H85 temperatures ranging from the mid teens(C) in central Kansas to near 20C along the Colorado border by this afternoon. Expect highs up into the lower to mid 80s(F) across west central and portions of southwest Kansas to the mid to upper 70s(F) in south central Kansas where increased cloud cover may limit climbing temperatures. Thunderstorm chances bump up a little Saturday as a progressive upper level trough pushes through the Intermountain West into the Western High Plains early in the period. Meanwhile, moisture will continue to advect northward ahead of the dryline with surface dewpoints reaching into the lower to mid 60s(F), particularly across south central Kansas.
Otherwise, VFR conditions are forecast throughout the TAF cycle with high pressure in place.
Deep layer ridging over the area will deliver another rain-free day to the forecast area. Look for afternoon highs in the lower 80s, expect for portions of the Big Bend where mid 80s are expected.
513 AM PDT Fri Oct 20 2017 Scattered showers will continue across the region this morning behind a robust cold front. As for the rest of the day, the trough axis swings through our forecast area with the cold temperatures aloft allowing widespread showers to continue. The bulk of precipitation will occur during the morning and early afternoon hours before the trough axis swings through Friday afternoon/evening. That will be briefly lived as a warm front pushes in from the west on Saturday morning. Once this warm front passes, the focus really is on the zonal flow and the atmospheric river slamming onto the Cascade range.
Lows should be warmer, into the lower 50s - with seasonable normal lows around 49 degrees. Warmer highs approaching the mid 80s is possible in a few spots if cloud cover holds off more than expected. Even warmer with lows only in the mid 50s east to lower 60s west.
In the middle and upper levels(700-200 mb), latest available satelitte imagery overlaid with model streamline analysis as of 900 am depict a NE to SW oriented positively tilted middle and upper trough well east of Nova Scotia to Florida. Upstream of that, the axis of a longwave ridge is located from Upper Michigan down through the Central Gulf of Mexico. Water vapor imagery delineated lots of dry air across Florida and the Keys at the bottom of the departing trough. The Florida Keys are along the southern periphery of this anticyclone. Temperatures over the islands are in the lower 80s with dewpoints in the mid 70s.
The associated cold front is forecast to move through western New Mexico late tonight and through central and eastern areas Saturday. High temperatures Saturday will be 10 to 15 degrees cooler across the northwest half and 5 to 10 degrees cooler elsewhere. Upstream upper level trough now coming ashore over the PACNW and northern CA.
1010 AM EDT Fri Oct 20 2017 Dry and warm conditions are expected through the weekend, as an upper ridge over the Gulf states moves east, and off the Carolina coasts.
These showers should gradually diminish through this afternoon, but the break will be short lived, as the tail end of the passing front will lift back north as a warm front tonight and tomorrow. Snow levels of around 4500 feet today will lift quickly above 9000 feet as the warm front passes. Major efforts today will focus on the warm frontal passage mentioned above. South winds will increase tonight as a warm front moves in, with MVFR with areas of IFR ceiling at the coast. The heavy swell will subside to moderate tonight, but another round of south gales will develop at that time as a warm front moves through the area.
High pressure will remain across the east coast/mid Atlantic with a trough of low pressure across the plains.
A large mid/upper ridge builds into the area with the low level ridge axis to the north of the area. skies will be mostly sunny with warm afternoon temps inland and cooler at the coast with breezy northeast winds.
Highs should be a degree or two warmer than yesterday.
/issued 402 AM CDT Fri Oct 20 2017/ SHORT TERM (Now through Saturday): 500 mb high pressure centered just east of the Mississippi River delta at the start of the short term forecast period will gradually shift east-northeast as a deep 500 mb trough moves into the Central Plains. Dry weather over the entire BRO CWFA today will yield to isolated showers over only the Lower Texas coastal waters tonight and Friday courtesy of this pattern.
825 AM EDT Fri Oct 20 2017 High pressure will maintain dry and warm weather through the weekend. High pressure will remain over the area today, keeping a dry and mostly clear forecast. The upper-level ridge will build through this evening, allowing our daytime highs to creep up from yesterday's readings. High pressure will remain anchored through the weekend, keeping it warm and dry.
1047 AM EDT Fri Oct 20 2017 Dry high pressure will hold over the forecast area through Saturday.
1049 AM EDT Fri Oct 20 2017 Strong high pressure will continue over the area, then shift offshore this weekend.
730 AM EDT Fri Oct 20 2017 High pressure will maintain dry and warm weather through the weekend. High pressure at the surface and aloft will again spread eastward across the Upper Ohio Valley today. High pressure will remain anchored through the weekend, keeping it warm and dry.
1119 AM EDT Fri Oct 20 2017 Slightly cooler weather is expected today in the wake of a cold front but temperatures are still expected to be above normal.
Expect strong southwesterly winds ahead of a cold front today.
A cold front is exiting the forecast area this morning with the upper level trough set to move over the area today. The upper level trough exits to the east overnight and a warm front will approach from the west arriving into the Cascades and central Oregon by early Saturday morning before sunrise. Will also see increasing southerly winds Saturday following the warm front and may need to issue some highlights for this but will further evaluate and consider for the afternoon forecast package. A warm front will be pushing into area between 6- 9Z with ceilings lowering and light rain spreading from west to east through the day Saturday.
813 AM EDT Fri Oct 20 2017 Dry high pressure will hold over the forecast area through Saturday.
A fast moving low pressure system will pass by to the north today while increasing winds across much of the Desert Southwest. Cooler air will also settle into the region as highs drop back closer to normal levels through Saturday.
733 AM EDT Fri Oct 20 2017 A large and persistent area of high pressure at the surface and aloft will remain over the eastern CONUS through the upcoming weekend.
Expect clouds to decrease from west to east thereafter as the said ua trough exits eastward. A low level thermal ridge will begin to spread over the area, and allow temperatures to rise a few degrees above normal this afternoon. This process will continue Saturday ahead of the next ua trough, with the thermal ridge aided by westerly downslope winds in spiking high temperatures around 10 degrees above normal.
High pressure centered over the Appalachians at this time, will eventually break down and/or head further east to the east coast today. During the day on Saturday, a cold front will be makings its way across the central Plains states.
The best chance for rain with this system will come later in the evening when the main system ejects out and the attendant cold front pushes through the area.
1237 PM EDT Fri Oct 20 2017 Dry and warm conditions are expected through the weekend, as an upper ridge over the Gulf states moves east, and off the Carolina coasts.
1215 PM EDT Fri Oct 20 2017 Dry high pressure will hold over the forecast area through Saturday.
1044 AM MDT Fri Oct 20 2017 Upper ridging continues across the eastern two thirds of the CWA with a trough moving onshore the Pacific NW coast. Gusty southwest flow over the High Plains will continue to bring much warmer than average temps to the area today. Upper trough will quickly approach today into tonight.
732 AM EDT Fri Oct 20 2017 A weak and dry cold front will continue to traverse the North Country through the overnight hours. Behind the front temperatures will be slightly cooler but high pressure quickly builds back in.
Cooler temperatures and brisk onshore winds will persist today. Rainfall totals have ranged from under a tenth of an inch to over three quarters of an inch, with the highest amounts falling in the North Bay. A warming trend will begin during the weekend as an upper level ridge builds over the state. Much warmer temperatures are then forecast early in the work week as the upper ridge strengthens along the West Coast and light offshore flow develops.
Seeing a bit of cirrus making its way northeast into eastern Kansas from earlier convection associated with the western CONUS longwave trough, and with south-southwest to south-southeast winds persisting in the lower levels, temps remain warm again early this morning. South winds continue to bring a slightly cooler and drier airmass into the area but temps still reach the upper 80s to lower 90s with apparent temps a few degrees higher.
with a majority of the east side valleys which have already had a killing freeze also near or below freezing.
539 AM 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.
The one exception to this could be out west along the Rio Grande where some convection across the lower Trans-Pecos may impact western Val Verde county.
632 AM CDT Sat Sep 23 2017 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.
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.
Upper ridge centered offshore and upper low over Idaho today. Upper ridge builds in stronger on Sunday which should decrease cloud cover some. Expect partly cloudy skies with temperatures a few degrees warmer.
Sunday should continue on the warm side, as high pressure centered northeast of the region controls the weather. Slightly lower thickness values from the upper low traversing westward should result in high temperatures a degree or two cooler, into the mid and upper 80s.
Huston Freezing or near-freezing temperatures have settled into the Arco Desert and Snake Plain, so current Freeze Warning looks good. Areas of Freezing Fog have developed and have been most impactful in the Teton Valley where near Zero visibilities have been reported at times.
WV imagery indicates a strong upper level trough of low pressure shifting slowly east-southeast across the Great Basin creating a southwest flow aloft across the Western High Plains. Near the surface, low pressure is anchored across southeast Colorado with an attendant stationary frontal boundary extending northeast into extreme northwest Kansas. An upper level low will move out of Nevada today then over Utah tonight.
655 AM 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.
The main change this period is to shift the highest precipitation amounts slightly westward again, and limit it to generally less than 2.
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.
An upper level low will move out of Nevada today then over Utah tonight.
High Surf and Strong Rip Currents This Afternoon and continuing East central Florida is situated between an upper low just north of the FL panhandle and Hurricane Maria well east of the central Bahamas near 72W. The low level ENE flow and fairly deep moisture across the area will support scattered to numerous showers and isolated storms moving onshore into the afternoon with short range models and the HRRR favoring higher coverage generally south of a Cape Canaveral to Kissimmee line.
An upper level low situated over our area with southerly flow bringing Gulf moisture and enhanced divergence on its east side over the Florida Peninsula and northeast Florida.
Weak instability will develop this afternoon courtesy of an area steep mid-level lapse rates near the core of the upper level low moving across central Nevada.
/issued 434 AM EDT Sat Sep 23 2017/ TODAY THROUGH SUNDAY: Large trough extending across the eastern US is expected to develop into a weak upper level low that meanders along the northern Gulf coast through the remainder of the weekend. The concerns today will be for a few stronger storms given the proximity of the upper low, especially along boundary collisions, and heavy rainfall.
/issued 417 AM CDT Sat Sep 23 2017/ SHORT TERM (Now through Sunday): The 500 mb ridging currently over the central and northeastern U. will be eroded by a deep closed moving in from the western states and a weaker closed low drifting west over the southeastern states. AS the 500 mb ridging gradually breaks over the RGV.
Otherwise cool conditions will persist this weekend as a low pressure system sits over the Great Basin.
The broad scale weather features reveal a significant upper trough over the western US that will guide and funnel moist air into the northern plains through Sunday.
TEC Previous Discussion: Upper trof over the region will shift slightly eastward over the next few days. Light showers moving out of south central Montana will lift across the western zones this morning before the focus shifts toward the North Dakota border as upper trof axis moves across the divide. Beginning Sunday night, the slow-moving, main low pressure trough axis will finally be moving through eastern Montana, which will push the chances for any remaining organized rain showers further east, in that SW flow aloft, which will have been impacting our SE zones for a few days.
958 AM EDT Sat Sep 23 2017 12Z sounding this morning showed flow aloft has shifted to the south, and this is due to the upper low over the Florida Panhandle continuing to slowly retrograde westward. Highs are forecast to be in the low to mid 80s for the coastal areas and the mid to upper 80s well inland.
Maria continues to move slowly north over the southern Atlantic keeping the ridging in place across the eastern conus with troughing remaining over the Rockies. At the surface, an area of low pressure was over northwest Minnesota with a trailing cold front back across far western Minnesota into Nebraska. Maria will continue to work north with the upper level ridge axis expected to gradually shift around to the north side of the hurricane but maintaining the ridge axis over the lower Great Lakes into the region. This will keep the troughing and the surface cold front well to the west of the area to maintain the dry conditions.
Iowa will remain between the western CONUS trough and Upper OH Valley ridge with insufficient moisture and forcing for any precipitation through the period. In fact, the current frontal boundary through the Siouxland area early this morning is expected to nudge slightly westward into tonight as mid level forcing expands into the Rockies and high Plains ahead of the slowly advancing long wave trough.
Many locations reached the lower 90s over central Wisconsin and even some locations over northeast Wisconsin include Sturgeon Bay and Oconto.
930 AM 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.
708 AM EDT Sat Sep 23 2017 Early morning light fog will burn off 13-14Z, with mainly clear skies and very light winds through the TAF period as the upper level ridge remains in place. 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.
1004 AM EDT Sat Sep 23 2017 Morning water vapor imagery shows an amplifying trough across the west, high pressure over the central part of the country, and an area of low pressure centered along the northern Gulf coast/Florida panhandle region. At the surface, Maria is moving north-northwestward over the western Atlantic while high pressure remains centered to our north. High pressure to the north will keep an east to northeast flow across the waters for the next several days with an overnight surge to around 15 knots or so.
Surface wise, Hurricane Maria is locate east of the central Bahamas, while our area lies on the southern periphery of a large, albeit weak continental anticyclone centered over northeast United States. With our region lying between Hurricane Maria east of the central Bahamas and a developing mid and upper level trough over the extreme southeast United States and the eastern Gulf of mexico, a typical moist and conditionally unstable air mass will remain in place.
/issued 453 AM CDT Sat Sep 23 2017/ (Today and Tonight) A highly amplified upper level pattern will continue across the CONUS the next 24 hours, with a deep upper level trough across the western states and an upper ridge situated over the Ohio and Tennessee Valley region. Temperatures will be a degree or two cooler today, with afternoon highs topping out in the upper 80s and lower 90s. Scattered showers and thunderstorms are expected to develop across the Permain Basin tonight, in advance of the upper trough. (Sunday) An upper level trough to our west will send a few disturbances northeast and combine with a low level southeast flow to produce isolated to scattered thunderstorms across the far western part of the area.
1105 AM CDT Sat Sep 23 2017 South/southwesterly winds continue in a very warm airmass, resulting in high temperatures once again in the low 90s.
627 AM CDT Sat Sep 23 2017 The cold front has continued to push farther south than expected. A cold front stretches from just south of North Platte to just north of Norfolk. This evening and overnight, the best chances for thunderstorms will remain across the High Plains of Nebraska where the best 850mb convergence is located.
/issued 344 AM CDT Sat Sep 23 2017/ A strong upper trough centered over NV and ID are expected to bring heavy showers and thunderstorms to the area this weekend as it slowly moves east.
South Texas will remain under a ridge axis positioned between the deep upper level trough over the Rockies and a weak cut-off low over the southeast US and northeast Gulf of Mexico. On Sunday the weak upper low will move eastward along the northern Gulf coast. Although moisture will be slightly lower, provided the proximity of the low, anticipate more scattered convection across the region on Sunday, mainly across the coastal areas and Victoria Crossroads. Temperatures over the weekend will be fairly persistent, with highs in the lowers 90s across the Coastal Bend to mid to upper 90s across the Rio Grande Plains, and lows staying in the 70s overnight.
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. Thus ridging influences sfc/aloft should result in VFR/SKC conditions thru 24/12Z.
507 AM MDT Sat Sep 23 2017 Moisture will continue to stream northward across Colorado through tonight, with both the upper level features and the surface cold front moving ever so slowly eastward. Meanwhile, showers are occasionally forming on the cold side of the cold front across the northwest corner of Kansas. There could be significant accumulations above 10-11 thousand feet, but much less at 9-10 thousand feet accompanied by quite a bit of melting as air and ground temperatures will be above freezing most of the time. If the low clouds thicken up quickly, we may still be too warm for today.
1100 AM CDT Sat Sep 23 2017 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.
An area of high pressure and an upper level ridge will remain in control of the weather through midweek.
The exception was the Twin Cities where they were remarkably still in the lower 80s! Dewpoints were in the mid to upper 60s. Today: Another sunny and hot day is in store as the high pressure surface and aloft remains locked in place. I will forecast highs in the lower 90s and with dewpoints in the mid to upper 60s, this will push heat index values into the mid 90s.
454 AM EDT Mon May 22 2017 Dry weather is in store for today as high pressure tracks across the Ohio Valley.