Aikyam-Lab/Synoptic-Bench huggingface dataset:
The GFS has a little bit of reformation around 12z, but most of the high resolution guidance keeps us dry through midday tomorrow with some development tomorrow afternoon over west Tennessee and northeast Mississippi near the Tennessee river and Alabama state line. Expect highs in the low 90s.
937 PM EDT Fri Aug 5 2022 All is quiet across our Northwoods late this evening as we remain directly under low level ridging with dry air thru the entire column. High pressure has helped to clear out the clouds around MBL and produce sunny to partly cloudy skies this afternoon.
The center of the 500 mb high pressure system is forecast to migrate northeastward over KS tonight and remain there through the Short Term period. Over western and north central areas, look for an uptick in convective coverage on Saturday afternoon and evening compared to today, since models depict a disturbance embedded in the periphery of the ridge tracking northward in the monsoon flow over western NM.
At the same time, a broad inverted trough sits east of the Bahamas and is sliding westward. An associated upper level low sits northwest of the Bahamas and also is sliding westward. Lastly, the subtropical ridge continues to gather strength with the axis continuing to lift northward this evening. Breezes will freshen overnight across the remaining waters as the subtropical ridge builds and the axis lift further north and away from our area.
715 PM EDT Fri Aug 5 2022 High pressure east of Bermuda will bring seasonable heat and isolated to widely scattered afternoon showers and thunderstorms over the next several days.
356 PM PDT Fri Aug 5 2022 Temperatures will begin to trend upward as high pressure builds over the Inland Northwest.
627 PM CDT Fri Aug 5 2022 (This evening through Saturday) Temperatures have warmed well into the 90s to around 100 degrees early this afternoon, with highs expected to be just one or two degrees cooler than yesterday. While we expect to continue to be warmer than normal on Saturday, temperatures should cool again by a few degrees, so will not re- issue the Heat Advisory for tomorrow. However, if it appears that temperatures and/or heat index values will be warmer on subsequent shifts, a new advisory may be issued.
326 PM MDT Fri Aug 5 2022 An upper trough is over western Canada and the Pacific Northwest with an upper ridge centered over the southern Great Plains this afternoon. The trough to our west should bring appreciable large- scale lift over our area as it moves eastward, with added lift from the right entrance region of a jet streak and mid-level frontogenesis. At the surface, high pressure will move from southern Alberta to the Dakotas, which will facilitate advection of cool air from the northeast into our area. This cooler air in the lower levels of the atmosphere will contribute to a more stable atmosphere that will limit thunderstorm development, though a few thunderstorms are still possible mainly in the mountains where instability will be a little greater.
Temperatures have already dropped into the lower 70s in most locations and mid to upper 60s higher elevations and southwest Virginia because of the rain cooled air.
With a humid air mass still in place across the area, temperatures will only fall into the low-to-mid 70s by early Saturday.
High pressure ridge axis north of the local Atlantic waters will result in winds SE/E 10-15 kts.
low temps will be capped by dewpoints in the lower 70s. The CWA will remain positioned beneath a weakness in the upper- level ridge on Saturday. In the continued absence of synoptic- scale forcing, convection will once again be diurnally-driven and will be modulated by mesoscale features such as outflow boundaries and differential heating along morning cloud decks and/or heating along the higher terrain across the far north. Martin Fcst period starts with continued ample moisture advection out of the SE between a dampening broad upper ridge in the central CONUS and the Bermuda ridge to the east.
831 PM EDT Fri Aug 5 2022 High pressure east of Bermuda will bring seasonable heat and isolated to widely scattered afternoon showers and thunderstorms over the next several days.
(Today and tonight) The 850 mb thermal ridge should be a little weaker today (850 mb temperatures about 3 degrees less than yesterday), so it shouldn't be quite as hot (highs today in the mid to upper 90s in the I-10 corridor and Hill Country, and upper 90s to around 102 in the Concho Valley/Heartland/Big Country.
Clear sky observed across the area, although the GOES16 satellite loop was showing invading cirrus into north central Kansas associated with MCS activity across Nebraska and South Dakota, as well as mid/high clouds over eastern Colorado aligned with a lee trough. Overnight lows again will be quite warm, in the the mid 70s most areas over the lower plains counties. A cold frontal boundary will be impinging on the northwest sections of the state, bringing scattered convection with locally heavy rain and probably a severe downburst wind risk by the late evening Sunday to our northern counties.
SHORT TERM (Now through Sunday): The proximity of an inverted 500 mb trough over inland Mexico, combined with deep tropical moisture (precipitable water values around 2 inches) will produce isolated to scattered showers and thunderstorms today, and convection more isolated in coverage on Sunday.
924 PM PDT Fri Aug 5 2022 Temperatures will begin to trend upward as high pressure builds over the Inland Northwest.
315 AM CDT Sat Aug 6 2022 Hot and dry weather conditions will persist across the region again today as the mid/upper ridge builds back across the area bringing rising heights/increasing thickness and a continuation of much above normal temperatures. Triple digit heat is likely across the forecast area with the highest temperatures topping out around 106.
139 AM EDT Sat Aug 6 2022 High pressure east of Bermuda will bring seasonable heat and isolated to widely scattered afternoon showers and thunderstorms over the next several days.
(Today) Mid-level ridge of high pressure centered over KS will maintain hot and dry weather.
444 AM EDT Sat Aug 6 2022 Periodic shower and thunderstorm chances will continue through Sunday as a slow, weak trough advances across the Ohio River Valley. According to RAP analysis, the trough axis continues to drape near south central Ohio and extend north along the Ohio River into northwest PA. 8 inches) and LCL to freezing levels maintain a height above 10kft. With the shift in the trough axis east of Pittsburgh by late afternoon, areas of heavy rainfall should remain focused near the Laurel Highlands. By Sunday, expect a shift in the mean flow with an advancing trough over the Great Lakes.
High pressure centered over the western Atlantic continues to build into the southeastern CONUS. Temperatures will climb back into the low to mid 90s and continue into Saturday. Lows tonight will be in the low to mid 70s, with upper 70s along the immediate coast.
329 AM CDT Sat Aug 6 2022 Weather during the short term will continue to be influenced by a weak shear axis within a broad upper level ridge spanning from the central to eastern U. This weakness in the ridge may help to focus slightly better coverage of shower and thunderstorm activity across portions of southwest Indiana and the Kentucky Pennyrile today, and less so on Sunday.
Given the high magnitude of low-level moisture (dew points of 73-77) and still weak surface flow, fog is again a possibility. While the slightly more favored area for fog is along and east of I-55, the higher dew point air is inching back north and there have been spotty showers further north, both of which support higher boundary layer moisture and possible fog too.
The GFS has a little bit of reformation around 12z, but most of the high resolution guidance keeps us dry through midday tomorrow with some development tomorrow afternoon over west Tennessee and northeast Mississippi near the Tennessee river and Alabama state line. Expect highs in the low 90s. Expect a little bit drier day for Saturday and Sunday with highs in the low 90s.
with the main upper ridge remaining just NW of AR over KS.
255 AM EDT Sat Aug 6 2022 High pressure east of Bermuda will bring seasonable heat and isolated to widely scattered afternoon showers and thunderstorms over the next several days.
(Today through Sunday afternoon) Currently have areawide tranquility thanks to continued high pressure across W TX. The next few days will be characterized by limited convective threats and slightly cooler temperatures than the past several days. Height pattern will fall over the region as the main ridge axis shifts to the central Mississippi Valley, carrying the warmest boundary layer temps off to the northeast.
Expect mainly cloud buildups over the mountains and mostly clear skies elsewhere over the weekend as the moisture tap is being shut off due to an upper-level low pressure system approaching Northern California.
Upper level ridging across the region will weaken some today and into tonight as a wave in the eastern Atlantic approaches the Carolina/Georgia coast early tomorrow morning. These increased PW values combined with the slight weakening of the upper level ridge will allow for increased shower and thunderstorm chances today (50-70%). Highs will be in the low to mid 90s with lows in the mid 70s. The upper level ridge that was in place at the beginning of the weekend will break down as an upper level trough moves in from the western Atlantic Ocean.
1145 PM EDT Fri Aug 5 2022 All is quiet across our Northwoods late this evening as we remain directly under low level ridging with dry air thru the entire column. High pressure has helped to clear out the clouds around MBL and produce sunny to partly cloudy skies this afternoon.
214 AM EDT Sat Aug 6 2022 High pressure off the Atlantic Coast ridges westward over Ohio through the weekend.
With diurnal heating and some upper forcing, numerous showers and thunderstorms are anticipated again, initially over the higher terrain. Additionally, fairly high freezing levels are anticipated with PWAT values exceeding 1.
421 AM EDT Sat Aug 6 2022 Discussion/Marine --Warm and humid weekend to start-- Dry air aloft with high pressure over the region will allow for warm advection today.
Forecast Highlights: - Continued heat through Sunday before a cold front brings some relief early week.
Temperatures are in the low to mid 70s at most locations early this morning with dewpoints in the low 70s. The upper level pattern features broad ridging across the much of the Eastern 2/3rds of the CONUS. The atmosphere remains hot and humid today with high temperatures climbing into the low to mid 90s. There is a weakness in the ridge over the area. There is no real synoptic lift but expect a few showers/storms will develop this afternoon with best chances for initiation over the higher terrain of northeast Alabama and southern Middle Tennessee.
South to southeasterly flow at the surface will increase under the main upper level-level ridging. Best chances remain across the east, with the lowest chances in the west.
Isolated afternoon showers and thunderstorms are possible today, with slightly better chances Sunday afternoon as a cold front settles southward.
215 AM EDT Sat Aug 6 2022 High pressure will remain centered offshore through tonight, with a weak trough of low pressure over the local area.
According to RAP analysis, the trough axis continues to drape across south central Ohio and extend north along the Ohio River into northwest PA. 8 inches) and LCL to freezing levels maintain a height above 10kft. With the shift in the trough axis east of Pittsburgh by late afternoon, areas of heavy rainfall should remain focused near the Laurel Highlands. By Sunday, the approach of a second trough from the northwest will add to the westerly flow but focus convection more to the northwest and later in the day on Sunday.
358 AM CDT Sat Aug 6 2022 Showers and thunderstorms continue to roll through the region on the cold front early this morning. The cold front will slide south through mid morning. An upper trough that will move in on Sunday will reinforce the cooler air and the shower activity.
1216 AM CDT Sat Aug 6 2022 (This evening through Saturday) Temperatures have warmed well into the 90s to around 100 degrees early this afternoon, with highs expected to be just one or two degrees cooler than yesterday. While we expect to continue to be warmer than normal on Saturday, temperatures should cool again by a few degrees, so will not re- issue the Heat Advisory for tomorrow. However, if it appears that temperatures and/or heat index values will be warmer on subsequent shifts, a new advisory may be issued.
Expect more robust convection later this afternoon as the ridge is forecast to weaken. Upper level ridging across the region will weaken some today and into tonight as a wave in the eastern Atlantic approaches the Carolina/Georgia coast early tomorrow morning. These increased PW values combined with the slight weakening of the upper level ridge will allow for increased shower and thunderstorm chances today (50-70%). Highs will be in the low to mid 90s with lows in the mid 70s. The upper level ridge that was in place at the beginning of the weekend will break down as an upper level trough moves in from the western Atlantic Ocean.
539 AM CDT Sat Aug 6 2022 Hot and dry weather conditions will persist across the region again today as the mid/upper ridge builds back across the area bringing rising heights/increasing thickness and a continuation of much above normal temperatures. Triple digit heat is likely across the forecast area with the highest temperatures topping out around 106.
647 AM EDT Sat Aug 6 2022 High pressure east of Bermuda will bring seasonable heat and isolated to widely scattered afternoon showers and thunderstorms over the next several days.
Forecast highlights in the short term period will be cooler temperatures and chances for showers today and tonight. Currently, west/southwest flow aloft with upper level ridging to our south and a long wave trough over the northwest CONUS. Temperatures will be much cooler for today thanks to the cooler air moving in behind the front and the abundant cloud cover, with highs today only in the 60s. Even cooler southwest where rain chances increase this afternoon.
/issued 328 AM CDT Sat Aug 6 2022/ SHORT TERM (Now through Sunday): The proximity of an inverted 500 mb trough over inland Mexico, combined with deep tropical moisture (precipitable water values around 2 inches) will produce isolated to scattered showers and thunderstorms today, and convection more isolated in coverage on Sunday.
Midlevel temps will be cooler over the TN River valley, in the vicinity of the weak shear axis. Rain chances will edge up on Sunday, as the weak shear axis and cooler 700mb temps retrograde westward.
The highest heat indices are likely in the HWO LIMITED (1/4) risk for heat area in some Delta areas mostly along and north of I-20 where heat indices will tick up to near criteria (105 F).
A very warm and humid day is in store for much of the region ahead of an approaching cold front. Clouds and the quicker arrival of the cold front will keep highs and subsequently heat index values lower across north- central Wisconsin. A cold front will bring increasing chances for showers and thunderstorms across north-central Wisconsin early this afternoon, then progress southeast over central and northeast Wisconsin later this afternoon, and eventually east-central Wisconsin this evening. The cold front will slowly track through the area overnight and into Sunday, providing several rounds of moderate to heavy rain to the entire region.
602 AM CDT Sat Aug 6 2022 (Today and tonight) The 850 mb thermal ridge should be a little weaker today (850 mb temperatures about 3 degrees less than yesterday), so it shouldn't be quite as hot (highs today in the mid to upper 90s in the I-10 corridor and Hill Country, and upper 90s to around 102 in the Concho Valley/Heartland/Big Country.
WV imagery indicates ridging aloft situated across the Central Plains. Near the surface, a weak cold front extends from northeast Colorado into central Nebraska while a lee side trough of low pressure extends southward near and along the Colorado border. Clear sky observed across the area, although the GOES16 satellite loop was showing invading cirrus into north central Kansas associated with MCS activity across Nebraska and South Dakota, as well as mid/high clouds over eastern Colorado aligned with a lee trough. Overnight lows again will be quite warm, in the the mid 70s most areas over the lower plains counties. A cold frontal boundary will be impinging on the northwest sections of the state, bringing scattered convection with locally heavy rain and probably a severe downburst wind risk by the late evening Sunday to our northern counties.
411 AM CDT Sat Aug 6 2022 Forecast highlights in the short term period will be cooler temperatures and chances for showers today and tonight. Currently, west/southwest flow aloft with upper level ridging to our south and a long wave trough over the northwest CONUS. Temperatures will be much cooler for today thanks to the cooler air moving in behind the front and the abundant cloud cover, with highs today only in the 60s. Even cooler southwest where rain chances increase this afternoon.
This dry air mass will remain over the region through Sunday with precipitable water values dropping below 1 inch over all areas except the lower Colorado River Valley and southern Mohave County where flow begins to turn southeast and open the door for some moisture influx Sunday afternoon. Temperatures will climb to near normal by Sunday with highs 100-105 across most desert zones and around 110 in the lower Colorado River Valley.
Weather during the short term will continue to be influenced by a weak shear axis within a broad upper level ridge spanning from the central to eastern U. This weakness in the ridge may help to focus slightly better coverage of shower and thunderstorm activity across portions of southwest Indiana and the Kentucky Pennyrile today, and less so on Sunday.
As the midlevel trough to the north passes through, the rain chances will gradually shift into northern WY this afternoon. Once the midlevel trough moves quickly east Sunday morning, drier air will begin to entrain back across the state, ending rain chances.
630 AM CDT Sat Aug 6 2022 (Today) Mid-level ridge of high pressure centered over KS will maintain hot and dry weather.
914 AM EDT Sat Aug 6 2022 Pattern remains fairly similar to the past couple days with a predominant low level E/SE flow across the region, as Atlantic ridge axis remains north of the area.
628 AM CDT Sat Aug 6 2022 Showers and thunderstorms continue to roll through the region on the cold front early this morning. The cold front will slide south through mid morning. An upper trough that will move in on Sunday will reinforce the cooler air and the shower activity.
716 AM EDT Sat Aug 6 2022 Aviation --Warm and humid weekend to start-- Dry air aloft with high pressure over the region will allow for warm advection today.
1030 AM EDT Sat Aug 6 2022 Lower tropospheric ridging across the western North Atlantic and southeast U. Aloft, the upper low to our southwest appears to be shearing through the southern Gulf, with the western Atlantic upper low continuing to slowly progress westward toward the southeast U. The lower level easterlies have increased since yesterday morning and were near 20 knots at 2K feet. Continuing from synopsis, robust high pressure across the southeastern United States will maintain moderate to occasionally fresh breezes across the Florida Keys coastal waters.
- Quiet the remainder of the period with broad high pressure generally in place over the upper midwest. Another issue as far as thunderstorm development goes is the sheer amount of moisture, as was alluded to in the previous AFD with PWAT values increasing to 2 inches or higher across the area, which generally will keep our lapse rates on the low end and hinder large scale thunderstorm growth. Rainfall will linger into Sunday as the upper level low pushes north of the Great Lakes, with wrap around showers to continue along a zone of h850 WAA, once again primarily in southern to southeastern Minnesota and western Wisconsin. Broad high pressure returns behind the departing system towards the beginning of the work week and staying in place for most of the coming week.
A more favorable flow pattern for daily thunderstorms will develop this coming week as the upper high becomes centered over the Four Corners region. Satellite imagery was showing a large thunderstorm complex over the Gulf of California this morning which should help advect some low level moisture into the lower deserts today. This moisture increase coupled with the influence of an inverted trough approaching the area from the east today and tomorrow will result in a noticeable upswing in thunderstorm coverage this weekend. Rain chances will continue to be elevated this coming week as a more favorable flow pattern develops with the upper high becoming centered over the Four Corners region.
BW Chattanooga Airport, TN 91 72 90 73 88 / 50 30 70 20 70 Knoxville McGhee Tyson Airport, TN 88 70 89 71 88 / 60 30 80 20 70 Oak Ridge, TN 87 70 89 71 88 / 60 30 70 20 60 Tri Cities Airport, TN 84 67 86 68 86 / 70 30 80 20 70.
The large scale pattern remains relatively unchanged as broad southeast high pressure and weak 700mb troughing over the lower Ohio River Valley funnel abundant gulf moisture into the region. Further aiding depression of convection will be a shift of the 700mb trough slightly east due to an upstream trough, which should foster more subsidence northwest of Pittsburgh. Mean flow will become slightly more zonal Sunday in response to a trough advancing into the western Great Lakes.
959 AM EDT Sat Aug 6 2022 High pressure east of Bermuda will bring seasonable heat and isolated to widely scattered afternoon showers and thunderstorms over the next several days.
The upper level low lingering over the E Pacific will drift slowly toward the ENE over the next few days. Light southerly winds will expanded into the northern outer waters today as a weak low pressure approaches from offshore.
Morning sounding shows that some drier air has worked into the area overnight as a trough passing to the north has allowed for more of a southwest flow to develop. Those areas include the Spring Mountains, the higher terrain and southern Clark County and far eastern San Bernardino county, and northern Lincoln County. Still, anything that does develop should remain fairly isolated and anchored to the higher terrain. This dry air mass will remain over the region through Sunday with precipitable water values dropping below 1 inch over all areas except the lower Colorado River Valley and southern Mohave County where flow begins to turn southeast and open the door for some moisture influx Sunday afternoon. Temperatures will climb to near normal by Sunday with highs 100-105 across most desert zones and around 110 in the lower Colorado River Valley.
SHORT TERM (Tonight through Sunday Night): A more obvious inverted upper trough in the model presentation will pass to the west tonight, ending the first day of slightly more active afternoon convection. Heat index values will top out in the 102 to 107 degree range Sunday afternoon, with the highest values in Starr and Zapata Counties.
Despite most of the area being on the cool side of a cold front, maximum heat index values in the advisory area are still on track to peak mainly in the 104-106 range as ambient air temperatures in the 98-105 degree range combine with dewpoints in the 60s to lower 70s.
Surface analysis this afternoon centers a ridge of high pressure along the Mid-Atlantic states while a cold front is located over portions of the Upper Midwest, Northern Plains, and the Rockies. Meanwhile, mainly rain free conditions are occurring across the forecast area with temperatures as of 2 PM CDT in the lower 90s across most locations.