Aikyam-Lab/Synoptic-Bench huggingface dataset:
At the start of the short term period, the CWA is underneath the base of an upper air trough with an eastward moving upper air ridge over the western CONUS. On Tuesday night, the flow over the CWA looks to turn more northerly after midnight as the front edge of the upper air ridge makes its way over the CWA with the trough moving just to the east. On Tuesday, forecast guidance shows the ridge continuing to move slowly eastward over the CWA changing the flow aloft more north- northeasterly.
Pronounced upper ridge over the area this evening with mostly clear skies and hot temperatures.
Meanwhile, a well-defined mid to upper level closed low is centered over the Florida Straits, enhancing the development of showers and thunderstorms across the Bahamas and Cuba. However, as the low pressure system has moved south, a more moist airmass has entered the Keys. Temperatures in the island communities are in the upper 70s to near 80F and the dew point values are in the lower 70s. From synopsis, high pressure centered east of the Mid Atlantic Coast will support moderate breezes through Wednesday night. Breezes will turn southeast and decrease slightly at the end of the week as high pressure recedes to the east into the western North Atlantic.
Latest model consensus still suggests that the areal coverage of rain will begin to increase more substantially from W-to-E during the mid-evening hours, as a pronounced vort max digging through the base of the longwave trough induces a strengthening southwesterly low- level jet across the TN Valley.
The dome of high pressure responsible for the hot weather in the Central Valley is currently around a 590 dm high. This dome of high pressure is keeping the hills warm with temps currently from the mid 80s to lower 90s across the hills from roughly 1800 to 2500 feet. So you dont have to climb too high to find the hot air associated with the upper ridge. The ridge will weaken slightly over the next 24 hours with surface pressure gradients trending stronger onshore.
519 PM MDT Tue Jun 1 2021 Northerly flow currently resides overhead as high pressure builds over the Intermountain West. Satellite imagery reveals diurnally driven cumulus clouds forming atop all ranges across the CWA, though towers with the highest vertical extent are focused along/east of the Divide. As high pressure fills into the Great Basin, an anomalously warmer air mass will follow suit.
829 PM CDT Tue Jun 1 2021 Broad southwesterly flow aloft continues to advect abundant moisture across the Mid-South downstream of a digging trough over the Central Plains. HREF QPF progs indicate a heavy rainfall potential over the next 48 hours or so as this trough slowly moves across the region. GOES-16 satellite trends this afternoon indicate a longwave trough axis over the Plains. A weak cold front will begin to move into the Lower Mississippi Valley on Wednesday.
Wednesday will start a slight cooling trend as high pressure gets pushed eastward. Ridging continues to influence short term weather in the CWA. As the ridge shifts east and weakens, a trough approaches and could bring temperatures down a few degrees as we progress through the week. A weak cold front associated with the trough will pass through the area Wednesday night.
559 PM CDT Tue Jun 1 2021 Rather moist low levels and relatively cool temperatures aloft under the upper trof has resulted in diurnally driven showers across central Kansas in an environment with weak instability though decent lapse rates. This upper trof will be slow to move and vacate the area until late Wednesday.
715 PM EDT Tue Jun 1 2021 High pressure lingers just offshore of the mid-Atlantic coast through midweek.
946 PM CDT Tue Jun 1 2021 An area of rain continues to approach the TN Valley this evening from the W, thanks to an approaching vort max rounding the base of an H5 trof across the Southern Central Plains. Otherwise, morning lows will fall into the lower 60s E/middle-to-upper 60s W at daybreak.
A progressive upper level trough over the central CONUS late Tuesday will affect the region during the short term period. One wave propagating through the trough will produce precip tonight in Wednesday, but models have trended drier for our area with this feature, holding the most significant precip to our west and north, and the new forecast reflects this. Another wave moving through the larger trough will affect us on Wednesday night, and with the entire regime shifting east and the system's surface cold front approaching, we will see our greatest POP with the second wave, along with the possibility of thunderstorms.
835 PM EDT Tue Jun 1 2021 High pressure will remain offshore through the end of the week. An upper level trough will reside to our west during the middle of the week, before progressing through at the end of the week. Gradually falling heights and lowering sfc pressures are expected Wed into Fri as an upper level trough over the middle of the country pushes east and the Bermuda high shifts farther east. Sct t-storms are expected to develop Wed mainly west of the Blue Ridge, then increase in coverage Wed night as srly flow strengthens further. During the past 24 hrs, the models have come into better agreement with respect to timing of upper trof axis crossing the area Fri morning and, as a result, now show a drier scenario for Fri and into the weekend.
As with yesterday, deep mixing of the boundary layer will limit overall upright instability amounts, though some degree of kinematic support will be afforded by the upper trough. A subtle upper wave cascades down the approaching upper ridge on Thursday afternoon and looks to being the risk of afternoon pulse showers and storms again to central Wisconsin before drier weather sets in for the end of the week and weekend.
349 AM EDT Wed Jun 2 2021 A low pressure system will impact the region today through Thursday evening as it tracks northeast across the Ohio Valley.
As temperatures return to near the convective temperature in the low and mid 80s around mid morning (15-16z), there will be the potential for convection to develop at pretty much any terminal. The upper ridge that extended over the CWA from the south is retreating southeastward while a trough deepens across the midsection of the country, extending from the Great Lakes to central Texas. Falling heights from the trough combined with increasing moisture and strong daytime heating will continue to enhance the spread of convection this afternoon. The increase coverage will also mean highs will be a degree or 2 cooler than earlier in the week. Stayed with NBM, which was slightly cooler than previous forecast.
The upper trough and its associated cold front will slowly move into the area tonight and progress across the region on Thursday, bringing additional rounds of scattered to numerous showers and thunderstorms across the Tennessee Valley. This time, locations east of I-65 will be better positioned for thunderstorms -- a few which could to strong to marginally severe given the higher shear values and lapse rates there.
350 AM CDT Wed Jun 2 2021 (Issued 350 AM CDT Wed Jun 2 2021) Today through Thursday: Precipitable water values will remain on the low side today, increasing a bit in the northwest this afternoon. Though a weak trough will be moving through, kept the forecast dry most places today due to the limited moisture. Onshore winds will keep it cooler near the lake today, with some uncertainty as to how far the lake breeze might make it inland Thursday.
205 AM MDT Wed Jun 2 2021 Northerly flow aloft continues today around the periphery of a ridge centered over the Great Basin. High temperatures will be in the mid to upper 70s and lows tonight in the lower 50s.
259 AM CDT Wed Jun 2 2021 A positively tilted trough will slowly drift east across the area today, gradually turning low level winds to a more westerly direction.
With lack of forcing and soundings showing a deep dry layer in the lower levels, would not expect much if anything to reach the ground. Look for lows in the lower to mid 50s. There will again be deep mixing with temperatures similar to today with highs in the lower 80s. By Thursday an upper level trough over the western CONUS begins to shift eastward, and this will influence our weather through the upcoming weekend with dry and warm conditions prevailing through the period.
The better chance for more widespread showers will come Wednesday afternoon as moisture increases area wide while the trough exits eastern Minnesota. Highs Wednesday will be running a few degrees above average in the low 80s, but the early wave of summertime heat will hold off until the end of the week. Light, but steady westerly 850 mb flow will advect a very warm thermal ridge axis east into the Northern Plains late this week, allowing for broad, upper-level ridging to follow. This week's warming trend quickens Thursday with forecast highs in the low 80s in west-central WI to upper 80s in western MN. The Buffalo Ridge could even see 90 or two. Due to being upstream of a trough, overall subsidence should keep any precip isolated. Thursday night's lows should only drop to the low to mid 60s.
BSH The upper trough will continue to slowly push east on Thursday with upper/mid level heights beginning to rise in its wake. Broad upper ridging will build into the middle portion of the country by the end of the week, eventually cutting off the base of the trough over the Southern Plains. Continued warm and moist advection will provide some weak low level ascent, but this will be counteracted to some degree by upper level subsidence from the building ridge.
Anticipating a bit cooler temperatures with highs in the upper 60s across the Southern Tier under thicker clouds, while east of Lake Ontario where some more sun will be realized highs will reach into the mid to upper 70s. Tonight through Thursday a mid level trough will slowly dig into the western and central Great Lakes, with a series of convectively augmented vorticity maxima rippling through the eastern flank of the digging trough from the Ohio Valley to the eastern Great Lakes.
Sunrise temperatures will be near the dewpoint, in the lower 50s.
IFR to MVFR ceilings have settled in for much of our TAF sites with the exception of KBVO which may see a period of MVFR ceilings in a few hours as the low level cloud deck continues to expand slowly westward.
1148 PM MDT Tue Jun 1 2021 Northerly flow currently resides overhead as high pressure builds over the Intermountain West. Satellite imagery reveals diurnally driven cumulus clouds forming atop all ranges across the CWA, though towers with the highest vertical extent are focused along/east of the Divide. As high pressure fills into the Great Basin, an anomalously warmer air mass will follow suit. The ridge of high pressure will remain anchored over the Great Basin on Thursday as a broad trough dominates the eastern CONUS.
Upper support over the central/eastern portions of the Southeast are initially suppressed with the area between the upper trough and an upper low over the western Caribbean, but through Thursday, the upper low shifts south with the mean upper trough shifting east a bit, along with the axis of better PoPs. Cooler temperatures will see the same shift as increased insolation inhibiting cloud cover and rain cooling moves over northwestern portions of the forecast area. For Wednesday, high temperatures in the low to mid 80s are expected west of the Alabama, with mid 80s to around 90 east. Have put/left areas of fog in for areas along and south of the Highway 84 corridor for now, and playing any Dense Fog Advisory by ear.
Additional precip will be possible across our eastern zones overnight as the cold front continues to push eastward. Slightly cooler temperatures can be expected overnight with lows in the mid to upper 60s. /Tonight through Tomorrow Night/ A very weak cold front continues to make its way through the region, while having the greatest effect not on temperatures, but on rainfall.
Instability profiles look fairly skinny given modest mid-level lapse rates, but proximity to the wave and slightly cooler mid-level temp profiles favors northern WI for the highest chances. Thursday: By mid week, broad upper ridge dominates the pattern over the western US with a long wave trough over the eastern US. Short wave trough moving through Thursday will support isolated storms in the far northern portion of our service area Thursday afternoon.
High pressure at the surface kept winds light, while plentiful dry air was observed in the DVN 02. A trough was in place aloft which did have enough moisture to have some scattered mid and high level clouds, but again the airmass was quite dry so no chances for rain in the area overnight.
151 AM MDT Wed Jun 2 2021 Water vapor imagery tonight shows the upstream ridge heading towards our area and increasing influence of anticyclonic flow aloft is drying out the airmass over western Montana. Ridge positively tilts into western Montana today bringing this influence the central part of the state so expect another day with light winds and less cloud cover. Additional sunshine, warming aloft and overnight temperatures that are getting warmer each night will lead to multiple days of summer temperatures reaching the upper 80s today and mid 90s Thursday which will likely set records at all climate sites.
CDG Chattanooga Airport, TN 79 65 80 64 83 / 30 60 60 30 20 Knoxville McGhee Tyson Airport, TN 77 65 79 63 82 / 30 50 80 30 20 Oak Ridge, TN 76 63 79 61 82 / 30 60 70 30 20 Tri Cities Airport, TN 78 63 77 60 80 / 30 50 80 50 20.
and Thursday A mid level short wave trough will track through the western Great Lakes during the late morning and afternoon hours, which is expected to set off another round of isolated to scattered showers and thunderstorms across the region. Highs today are generally expected to be in the middle to upper 70s, with a few 80 degree values possible, with cooler temperatures near Lake Michigan. The showers and thunderstorms should die off with the loss of daytime heating during the overnight hours; however, CAMs models do continue some isolated activity across the north tonight with the trough still across the region.
An area of rain continues to approach the TN Valley this evening from the W, thanks to an approaching vort max rounding the base of an H5 trof across the Southern Central Plains. Otherwise, morning lows will fall into the lower 60s E/middle-to-upper 60s W at daybreak. A deep layer of moderately strong southwesterly flow is expected to continue across the TN Valley on Wednesday and Wednesday night, as the vort max noted in the near term discussion progresses eastward across the Ozarks and into the Lower OH Valley by 12Z Thursday. Due to uncertainty regarding the speed of a slow-moving cold front, we will maintain fairly high morning POPs for the southeastern portion of the CWFA on Thursday, before ending rain chances during the evening hours.
405 AM EDT Wed Jun 2 2021 High pressure over the Atlantic siphons deep tropical moisture into the Carolinas through the end of the work week, creating elevated rain chances and coverage. Latest sfc analysis shows high pressure centered off to the NE with a stalled frontal boundary just off the Carolina coast. High temps in the low/mid 80s. Offshore Atlantic high pressure and an upper trough over the Mississippi River Valley will work together to siphon warm, muggy air into the Carolinas.
249 AM CDT Wed Jun 2 2021 Early this morning a low amplitude upper level trough axis extended from western IA, southwest across central KS, southward into north TX. Today the upper level trough axis will slowly shift east across the CWA into western MO.
The upper-level trough supporting this convection will shift very slowly toward the southeast today, and with weak instability and weak shear, disorganized convection could develop almost anywhere ahead of (or near) the trough axis.
Currently, temperatures are in the lower 70s with filtered sunshine. An isolated shower or two can't be ruled out overnight near Highway 24, and overnight lows will fall to the lower 50s. Finally, an afternoon lake breeze will once again move inland and keep lakeshore locations a few degrees cooler. Borchardt 140 PM CDT The trough axis will only slowly move across northern Illinois on Thursday, providing support for isolated diurnal showers and thunderstorms, possibly along the lake breeze. The 12z NAM is a bit more aggressive with a stronger vort max on the back side of the trough and brings this energy through northern IL in the afternoon.
An upper ridge positioned across the area through Wednesday with warm, sunny weather. Cooler marine air Thursday as a weak front weakens over the coastal waters.
The nearly stationary mid to upper level area of low pressure will remain in place over the Bahamas on Wednesday. Low pressure remains aloft to the east of South Florida near the Bahamas. At the surface, Atlantic high pressure will keep a steady easterly flow pattern over the region through the short term forecast period. Overall, a summerlike pattern has taken hold over South Florida aided by some extra moisture and cooler air aloft.
1143 PM CDT Tue Jun 1 2021 Rather moist low levels and relatively cool temperatures aloft under the upper trof has resulted in diurnally driven showers across central Kansas in an environment with weak instability though decent lapse rates. This upper trof will be slow to move and vacate the area until late Wednesday.
1115 PM MDT Tue Jun 1 2021 An amplified upper level ridge will continue to build across the western CONUS over the next 36 hours. The flow on the downstream side of this ridge is northerly, so this evening's high-level cirrus clouds will drift southward overnight. Deep subsidence hinders cloud cover and showers, although a few isolated cells could still form over the highest terrain. Overnight lows on Thursday morning remain mild and a few degrees warmer than the previous night.
214 AM MDT Wed Jun 2 2021 An upper ridge will over the forecast area today and Thursday with hot and dry weather.
A look at GOES mid-level water vapor imagery this morning shows positively-tilted troughing in place across the central CONUS; aiding in the ignition of overnight convection in the Southern High Plains.
GOES water vapor imagery depicts a broad positively tilted upper trough across the Plains. The slow progression of the upper trough will allow showers and storms to linger mainly near the TN River and portions of northeast MS during the early part of Thursday.
324 AM CDT Wed Jun 2 2021 The unseasonably cool, unsettled weather pattern will continue across the region today, with high temperatures this afternoon expected to be several degrees warmer than yesterday, but still below normal for this time of year.
453 AM EDT Wed Jun 2 2021 An upper-level composite analysis this morning reveals a weakening mid- to upper-tropospheric cold-core cyclone centered along the north-central coast of Cuba, near the Old Bahama Channel. Lower-tropospheric flow across the Florida Keys is east-southeasterly, primarily driven by a large subtropical anticyclone centered over the North Atlantic east of Bermuda. The weakening nearby mid/upper low has led to an increase in static stability across the Florida Keys and adjacent coastal waters, and lightning has been absent this morning given cumulus congestus with tops generally under 20,000 feet elevation.
An upper level trough will extend from the Great Lakes southwest into north Texas. Tonight, a thermal ridge will develop across the Central and Northern High Plains. Expecting a fairly strong inversion inversion in the low levels with lows from the low to mid 50s. Thursday, the upper ridge across the western U.
1135 PM MDT Tue Jun 1 2021 At the start of the short term period, the CWA is underneath the base of an upper air trough with an eastward moving upper air ridge over the western CONUS.
Upper level analysis shows ridge axis over the Pacific coast states, with north-northwest flow on the east side across the Rockies and high Plains.
The upper level trough axis will remain to out west this morning then finally push eastward this afternoon. Look for highs in the upper 60s to mid 70s with the warmer temperatures over southeast Kansas and western Missouri. With loss of heating and the trough axis east of the area tonight, expect mainly dry conditions, with decreasing clouds across the west.
By later this afternoon convection is expected to develop along the higher terrain of central/eastern New Mexico. Highs will also be a bit warmer tomorrow with highs approaching 80. Wednesday night into Thursday, a large amplitude ridge axis centered over the Intermountain West will begin to break down and shift east as a robust upper trough takes shape over the Gulf of Alaska and begins to dive southeast. The exact duration that upper level northwesterlies will remain in place overhead is uncertain, as this depends on how quickly the ridge flattens and how quickly the Baja low ejects northeastward.
A weak cold front was located just south of a Fredericksburg to San Macros to La Grange line at 05Z, and was moving slowly south.
The good news, beyond the low shower/thunder chances today, the forecast is looking dry well into the weekend.
As the upper trough finally pushes east of the Plains later today, the main focus for showers will shift eastward to the point that we may get a break in the early afternoon hours. The upper trough will linger over the region Thursday, and with some better heating, diurnal convection will be possible mainly over the eastern third of the region. The 18Z ECENS is similar, so our QPF may be a bit on the high side, especially given the meager instability expected.
Tonight Through Thursday Quite the contrast in temps and dewpoints across the state this afternoon as a warm front attempts to lift north into the area. While locations across northern Arkansas are flirting with record low highs, southern and portions of central AR have climbed to near 80 F with dewpoints in the lower 70s F. With the accompanying H500 trough overhead slowly shifting east, precip chances won't wrap up quickly.
The main concern through 15Z will be the low probability occurrence of TSRA at HOB and then again MAF/HOB/CNM toward the end of this forecast period (06Z Thur).
High amplitude upper level ridge over the northern Rockies will leave the CWA under northwesterly flow aloft. With the wind shift, warmer low level temps, and more sunshine, highs today should reach the 80s for most locations.
Currently, there is an area of low pressure in the mid/upper levels of the atmosphere (being reflected at the surface over north central South Dakota), slowly churning along east-southeastward across the Dakotas. The area of low pressure aiding the development of these sct'd showers/storms will slowly work off into Minnesota overnight, taking with it any remaining PVA for precip. This continues into the weekend while the large upper level ridge out west continues its expansion over into the plains region.
1028 PM MDT Tue Jun 1 2021 Water vapor shows short wave crossing western SD/western NE early this afternoon, with large scale ridge extending westward to the west coast. At the surface, weak trof is located just southeast of the Black Hills and advancing eastward. A few showers/storms have developed early this afternoon, generally along and east of the surface trof where MLCAPE has increased to nearly 500J/kg. Showers/isolated non-severe storms will continue near/east of the surface trof into the early evening before diminishing with loss of insolation. The rest of the week will bring much warmer temps and dry conditions as massive upper ridge builds into the Plains.
/issued 829 PM CDT Tue Jun 1 2021/ Broad southwesterly flow aloft continues to advect abundant moisture across the Mid-South downstream of a digging trough over the Central Plains. HREF QPF progs indicate a heavy rainfall potential over the next 48 hours or so as this trough slowly moves across the region. GOES-16 satellite trends this afternoon indicate a longwave trough axis over the Plains. A weak cold front will begin to move into the Lower Mississippi Valley on Wednesday.