Aikyam-Lab/Synoptic-Bench huggingface dataset:
Local dew points will decrease slightly into the lower 70s, keeping the area just below criteria for a subsequent Heat Advisory Sunday afternoon. With that said, heat index values near 100 degrees are likely across northern Missouri, with widespread air temps once again peaking in the low 90s. Increased temps will remain in place through the upcoming week, while the upper-level ridging pattern eventually gives way to zonal flow aloft. Widespread appreciable rain chances, however, will hold off until the late week and early weekend as the upper-level pattern becomes a bit more defined and surface convergence increases ahead of cooler air mass approaching from the north.
Strong mid level ridge to remain in place over the Plains with a northwest flow through the Great Lakes.
But a high pressure ridge has already started building into the region this afternoon and capped them off, keeping them from growing into any showers or thunderstorms in Montana, though a few sprinkles cannot be ruled out. In central Idaho, isolated showers have already started to the west, closer to the cut off low pressure system over the Pacific Northwest. All the sun today and the building ridge is causing warmer temperatures than we've seen for a few days.
354 PM CDT Sat Jun 29 2019 Large scale flow not changed a whole lot over the last 24hrs with a well amplified ridge in control over the central CONUS with an upstream positive tilt trough extending from British Columbia to off the the western U. Thunderstorms are progged to form along a inverted surface trof extending from low pressure over northeast CO.
306 PM CDT Sat Jun 29 2019 An upper low over LA, retrograding beneath a central CONUS ridge, is forcing convection across SE OK this afternoon. Southeast flow aloft will prevail on the eastern side of the upper low which will move into TX on Sunday. Ridging is expected to eventually retrograde back to the western CONUS with broad troughing setting up over the northern Plains, Great Lakes and Northeast.
This activity is largely diurnally driven and should dissipate around or shortly after sunset, but will hold onto good rain chances over western areas where better MSTR resides and in closer proximity to the retrograding upper trof. This inverted trof, over AR/LA this afternoon, is progged to continue to the W/SW tonight, and be situated over E/SE TX by tomorrow. A wedge of slightly drier air wrapping into the ERN flank of the trof, as noted on WV satellite imagery and partly evidenced by the relative lack of convection across South Central LA, is expected to work as far west as the Sabine River.
The moisture and heat to remain in place tonight as the thermal ridge builds slightly north and east into IA/SD/MN tonight into Sunday. Some storms have already formed in far NW ND and more expected to develop into an MCS tonight which is expected to ride down the instability gradient and edge of the thermal ridge across MN and possibly into Iowa late tonight. Moisture is expected to pool beneath the thermal ridge with the heat continuing ahead of that boundary moving southward into the region. This boundary is associated with an upper trough moving across south central Canada. Therefore will go ahead and issue another heat advisory for Sunday afternoon/early evening with heat index values again to rise into the low 100s and around 105.
151 PM CDT Sat Jun 29 2019 High pressure dominates the atmospheric column thru the entirety of the short term forecast period, while the active jet stream stays to our north.
138 PM EDT Sat Jun 29 2019 Showers and thunderstorms will accompany a cold front crossing the region later this afternoon and into the evening. Despite slightly warmer temps aloft, sufficient Sufficient instability, steep lapse rates, and dry air aloft will be supportive of isolated severe storms with damaging wind along with small hail. The cold front will reach the I-80 corridor this evening and progress southward overnight, pushing a fairly broken line of thunderstorms south and east. Dry and cooler air behind the front will end storm chances. Less humid air and cooler temperatures expected on Sunday behind the aforementioned front.
237 PM EDT Sat Jun 29 2019 A cold front pushes south into the area on Sunday.
This will pretty much repeat every day this week as the Mid-South remains on the periphery of an upper ridge. The ridge will gradually shift from the Midwest to the Southeastern United States over the course of the next seven days. Highs will generally be in the lower 90s.
1119 AM MDT Sat Jun 29 2019 Very strong ridge of high pressure remains across the Great Plains, with deep southwest flow across the northern High Plains. Downsloping across the northern Black Hills area is keeping adjacent foothill temperatures in the low 80s. Highs well ahead of the low over central SD will reach will into the 90s to just over 100 degrees today. Across northeast WY where the front is expected to arrive this morning, highs will be in the lower to mid 80s.
Despite slightly warmer temps aloft, sufficient Sufficient instability, steep lapse rates, and dry air aloft will be supportive of isolated severe storms with damaging wind along with small hail. The cold front will reach the I-80 corridor this evening and progress southward overnight, pushing a fairly broken line of thunderstorms south and east. Dry and cooler air behind the front will end storm chances.
/28/ Dry weather continues to occur this morning as the upper low that has been responsible for our recent stormy weather continues to track to the west. Moist southeast flow on the east side of the low will combine with daytime heating to bring scattered afternoon thunderstorm activity to the forecast area, but without the colder air aloft/ instability and lift associated with the mid/upper low, these storms will be disorganized and more ordinary than recently experienced with vertical totals generally less than 25.
109 PM CDT Sat Jun 29 2019 As of 18Z Saturday afternoon, an expansive midlevel ridge continues to be anchored across the Central US.
Cold front was crossing the area overnight with a jet max over central Montana. Heights begin to build over the area today in the wake of the cold front. High temperatures will range from the middle 70s over western areas to the lower 80s over eastern areas today. The biggest change in the extended is that the models are showing less spread with the evolution of the trough moving through the area mid-week. By mid-week as the aforementioned trough moves into the Pacific Northwest, flow will turn more southwesterly. Reimer The cold front has passed through SE Montana, and lower CIGs will persist through the day with mainly VFR conditions.
Dry weather continues to occur this morning as the upper low that has been responsible for our recent stormy weather continues to track to the west. Moist southeast flow on the east side of the low will combine with daytime heating to bring scattered afternoon thunderstorm activity to the forecast area, but without the colder air aloft/ instability and lift associated with the mid/upper low, these storms will be disorganized and more ordinary than recently experienced with vertical totals generally less than 25.
Coastal ridge/Great Plains trough in the upper levels will continue its southwest flow, occasionally bringing in enough moisture to trigger mountain-based thunderstorm and shower activity. The weak trough on Sun will elevate winds in the Snake River plain, but at this time are expected to stay below Lake Wind Advisory.
1110 AM MDT Sat Jun 29 2019 Latest upper level water vapor imagery shows a deep trough just off the western coast of the CONUS and a persistent ridge over the central CONUS. The same trough that is the star of the show on Saturday will provide a rich environment for severe storms on Sunday. The GFS keeps the higher dewpoints in the Panhandle. The NAM does seem to be slightly aggressive for Sunday, but many of the high resolution models are in agreement on deep instability and strong shear and helicity. As the upper level trough continues to move east, multiple rounds of precipitation are expected. Upper level vorticity advection will increase over the high plains producing strong and consistent upward omega values. Southwest flow may mitigate some of the lower RHs due to moisture advection.
Today and tonight A weak cold front has moved through northern portions of the forecast area (FA) this morning and continues to slowly make its way southward.
1149 AM MDT Sat Jun 29 2019 The forecast area remained between a high centered over the southern Plains and a trough off the West Coast. The trough to the west fills early in the coming week which allows the high over the southern Plains to expend westward across the Desert Southwest.
245 PM CDT Sat Jun 29 2019 An upper level ridge is centered over the central part of the country with an upper trough over the Pacific Northwest. Temperatures today may be a degree or two warmer than yesterday but will be near normal. Upper ridging continues into Sunday with temperatures about a degree or two warmer than today.
05Z RAP tropopause analyses and aircraft obs showed a ridge from Baja CA acrs the Nrn Plns into Cntrl Canada. with a cut-off low over the GlfMex. and a trof was over the Pac NW. Surface: The pres grad was wk with high pres over the Mid-Atlc and a trof in the lee of the Rckys. This low will head into the Canadian Prairies and as that occurs the cool front will emerge into the Dakota's this afternoon. A ridge over the Plns with trofs over the NW and NE USA. a trof to the lee of the Rckys.
That said, indications are that it will be a few degrees cooler than today as the ridge axis shifts slightly eastward.
Overnight low temperatures are expected to be in the lower 70s for inland areas and as high as the mid 70s for areas near coastlines. PWATs are going to drop on Sunday as the flow veers about to a more northwesterly direction as a result of the high pressure ridging developing to the west over the Gulf.
1118 AM EDT Sat Jun 29 2019 Surface observations this morning show our area in a relatively weak pressure gradient with cu beginning to develop across the higher elevations. Expect a few afternoon thunderstorms to develop across the higher elevations, but expect coverage to be less than yesterday with lower mid-level lapse rates and instability. Chattanooga Airport, TN 92 72 93 72 / 20 10 20 10 Knoxville McGhee Tyson Airport, TN 91 69 91 70 / 20 10 20 10 Oak Ridge, TN 92 70 92 71 / 20 10 20 10 Tri Cities Airport, TN 91 66 88 65 / 20 20 20 10.
A trough of low pressure has advance north across the peninsula of Florida bringing a rich tropical airmass along with it, prompting an environment favorable for more widespread coverage of intermittent showers and thunderstorms through the day and night hours. The deep layered ridge of high pressure to the east of our region over the Atlantic continues to provide a guiding southerly flow that is light enough to allow for sea breeze development.
Lows tonight will be in the lower 70s. Unsettled weather will continue on Sunday, as an upper level trough in the northeastern U. continues to break down ridging over portions of the southeastern U. Updated at 310 PM EDT Sat Jun 29 2019 Models have sped up timing of precip moving into the region as our area is in the northerly flow ahead of a ridge over the Central Plains.
The mid/upper level ridge should flex its muscles more on Sunday as heights build eastward. Yet another ridge-running MCS will probably evolve during the day on Sunday, but it should move east of the CWA. For now maintained a dry forecast however due to the expectation that the mid/upper level ridge does indeed strengthen across the Mississippi Valley, which should help inhibit any convective development. Temperatures will remain seasonably hot as highs top out mainly in the low 90s. The mid/upper level ridge will be stubborn and slow to breakdown. The GFS flattens out the ridge a bit sooner than the ECMWF. Sensible weather wise, this translates to higher chances for thunderstorms, more cloud cover, and slightly cooler temperatures.
For Sunday, temperatures will be a bit cooler as we'll be on the north side of the passing boundary.
High pressure will bring hotter temperatures the next few days. Still looking at hotter than normal high temperatures the next few days as high pressure aloft remains in place. The best chance for wetting rain will generally be across the higher terrain.
Weak upper low continues to drift southwest and is now over TX/LA, with a SFC/LL high set up over the mid-south.
More widespread convection exists just west of our CWA oriented along the northwest flank of an inverted upper level trough which was the culprit of our convection late last night and through the daytime hours today.
321 PM MDT Sat Jun 29 2019 Current surface analysis shows slow moving cold front from north central to southwest SD and into southeast WY. Upper level analysis shows trough along the Pacific NW coast, with southwest flow across the western US into the high plains. Ridge has shifted to the east of the area. Cooler and slightly drier air will allow temps to drop to the upper 50s to mid 60s in most areas by Sunday morning. However, humidities will stay on the higher side as dewpoints look to be in the upper 50s and 60s.
Though strong subtropical mid/upper level ridge is providing a CAP to area and limiting convective development over much of CWA so far today. Mid/upper level ridge continues to build a bit stronger into IL on Sunday with 500 mb heights rising to 591-593 dm by midday Sunday, and this will suppress convection over portions of central and sw CWA. Expect another muggy night with lows in the lower 70s.
/issued 245 PM CDT Sat Jun 29 2019/ An upper level ridge is centered over the central part of the country with an upper trough over the Pacific Northwest. Temperatures today may be a degree or two warmer than yesterday but will be near normal. Upper ridging continues into Sunday with temperatures about a degree or two warmer than today.
607 PM CDT Sat Jun 29 2019 Large scale flow not changed a whole lot over the last 24hrs with a well amplified ridge in control over the central CONUS with an upstream positive tilt trough extending from British Columbia to off the the western U. Thunderstorms are progged to form along a inverted surface trof extending from low pressure over northeast CO.
The upper low that had been responsible for our more organized convection continues to move west.
/Issued 306 PM CDT Sat Jun 29 2019/ An upper low over LA, retrograding beneath a central CONUS ridge, is forcing convection across SE OK this afternoon. Southeast flow aloft will prevail on the eastern side of the upper low which will move into TX on Sunday. Ridging is expected to eventually retrograde back to the western CONUS with broad troughing setting up over the northern Plains, Great Lakes and Northeast.
A moist se flow will transition to a westerly flow late tonight and Sunday as the mid level trough off the Fl east coast shifts eastward and a deep layer ridge builds to the south. Potential for overnight showers and storms to develop over mainly the offshore waters due to proximity of upper trough. Winds will become westerly later tonight and Sunday as a ridge of high pressure builds to the south.
As of 18Z Saturday afternoon, an expansive midlevel ridge continues to be anchored across the Central US.
517 PM MDT Sat Jun 29 2019 Troughing along the west coast of NOAM and ridging anchored over the high plains is keeping a decent fetch of southwest flow from the subtropics into the Intermountain West. This moisture will again fuel orographic thunderstorm activity this afternoon with outflow winds the main concern as the lower layers are still relatively dry. The flow becomes more zonal through the upcoming week as the Plains high deamplifies and the western trough fills a bit. Diurnal shower/thunderstorm coverage will then decrease from mid week onward and drier air is forced into the area by low pressure digging into the Southwest.
620 PM CDT Sat Jun 29 2019 Typical summertime upper level ridging is established across much of the Central/Southern Plains into the desert southwest. The exception is across the Northern Plains on the norther periphery of the ridging, where several thunderstorm complexes have dove southeast through the Mississippi Valley the last few days. A cold front will slowly sag into northwest Nebraska tonight as the ridge weakens and begins to flatten slightly. The upper ridge begins to break down and flatten further Sunday, allowing a cold front to slowly move southward across northern Nebraska and the Sandhills.
1045 PM EDT Sat Jun 29 2019 An upper-level composite analysis this evening reveals a deep layer mean anticyclone centered over the Atlantic east of the Bahamas. We did shave back precipitation probabilities by about 10 percent over the Keys and adjoining coastal waters given the observed sounding thermodynamics, but indicated higher probabilities over the lower Straits of Florida where highest coverage of rain and thunder has been observed. A high pressure cell from the western North Atlantic to the Florida Peninsula will weaken and shift southward overnight.
00Z Upper air analysis places an upper level low near the Texas/Louisiana border. This will pretty much repeat every day this week as the Mid-South remains on the periphery of an upper ridge. The ridge will gradually shift from the Midwest to the Southeastern United States over the course of the next seven days. Highs will generally be in the lower 90s.
519 PM MDT Sat Jun 29 2019 Current surface analysis shows slow moving cold front from north central to southwest SD and into southeast WY. Upper level analysis shows trough along the Pacific NW coast, with southwest flow across the western US into the high plains. Ridge has shifted to the east of the area. Cooler and slightly drier air will allow temps to drop to the upper 50s to mid 60s in most areas by Sunday morning. However, humidities will stay on the higher side as dewpoints look to be in the upper 50s and 60s.
305 PM MDT Sat Jun 29 2019 Troughing along the cold coast of NOAM and ridging anchored over the high plains is keeping a decent fetch of southwest flow from the subtropics into the Intermountain West. This moisture will again fuel orographic thunderstorm activity this afternoon with outflow winds the main concern as the lower layers are still relatively dry. The flow becomes more zonal through the upcoming week as the Plains high deamplifies and the western trough fills a bit. Diurnal shower/thunderstorm coverage will then decrease from mid week onward and drier air is forced into the area by low pressure digging into the Southwest.
An upper level trough axis continues to move westward across LA toward eastern portions of TX this afternoon, while another weak mid level trough axis was located over the FL peninsula. Weak ridging aloft will build northwestward across the eastern Gulf of Mexico and adjacent southeast states Sunday. Afternoon temperatures will be a little warmer, ranging from around 90 to the mid 90s inland and in the upper 80s along the coast.
The actual cold front is still projected to cross the region as the night progresses.
The forecast area will remain in deep south-southwest flow, stuck between an upper ridge of high pressure over the central US and persistent upper troughing over the Northeast Pacific.
While this will mainly increase mid and high level cloud cover, scattered showers and thunderstorms are possible especially over the higher terrain of central and northern Utah.
A persistent upper trough will keep the potential for afternoon and evening showers and isolated thunderstorms across the mountains again Sunday with relatively dry conditions in the lowlands.
617 PM CDT Sat Jun 29 2019 Updated aviation section for 00z taf issuance High pressure dominates the atmospheric column thru the entirety of the short term forecast period, while the active jet stream stays to our north.
/issued 200 PM CDT Sat Jun 29 2019/ Stout upper ridge of 594 dm is elongated from central Miss Valley SW into Northern Mexico and will continue to dominate for a few more days with seasonably warm temperatures and limited instability due to weak subsidence aloft and warm mid level temperatures. Feature of interest continues to be upper low/trough located this morning across SE Texas.
Chattanooga Airport, TN 72 92 72 94 / 10 30 10 20 Knoxville McGhee Tyson Airport, TN 69 90 70 91 / 10 20 10 10 Oak Ridge, TN 70 91 70 92 / 10 20 10 10 Tri Cities Airport, TN 66 87 65 88 / 20 30 20 10.
Similar conditions expected across the area tomorrow with low pressure off the Oregon coast, and isolated activity possible across eastern Oregon.
Strong ridge axis over western Kansas as of midnight, with strong subsidence and a clear sky. Sunday will remain hot, but about 2-3 degrees cooler than Saturday. Still expecting upper 90s across the northern zones, closer to the core of the remaining ridge axis.
323 AM CDT Sun Jun 30 2019 Slight mid/upper level troughing will extend into northern portions of the ArkLaMiss today and this could help to focus diurnally driven convective precipitation over north central MS as we go into the afternoon.
1136 PM MDT Sat Jun 29 2019 Troughing along the west coast of NOAM and ridging anchored over the high plains is keeping a decent fetch of southwest flow from the subtropics into the Intermountain West. This moisture will again fuel orographic thunderstorm activity this afternoon with outflow winds the main concern as the lower layers are still relatively dry. The flow becomes more zonal through the upcoming week as the Plains high deamplifies and the western trough fills a bit. Diurnal shower/thunderstorm coverage will then decrease from mid week onward and drier air is forced into the area by low pressure digging into the Southwest.
345 AM CDT Sun Jun 30 2019 High pressure aloft will gradually build east from the Plains into the mid MS River and lower OH River Valleys during the short term. However, a new fly in the ointment comes with the possibility of an MCS rotating southward around the eastern periphery of the high this afternoon and early evening.
1152 PM EDT Sat Jun 29 2019 A cold front will settle south through the forecast area this evening. Scattered strong thunderstorms will accompany the passage of the cold front.
350 AM CDT Sun Jun 30 2019 Isolated showers continue to develop around the western edge of an upper level trof that is spinning nearly overhead this morning as evidenced by observed storm motion. At the surface, prevailing high pressure is resulting in calm winds with the saturated ground allowing for another round of patchy light fog development. The upper trof is progged to continue slowly retrograding westward into east Texas through the day with showers and thunderstorms becoming more numerous across the region by late morning with the addition of daytime heating.
Upper level ridging remains in place over the central part of the country, with low pressure both to the west and east. At the surface, high pressure continues to move to the northwest into the area. Temperatures will likely be a degree or two cooler as well, which should keep heat indices below 100 degrees for most of the area. However, heat indices between 100-105 degrees are expected in our far northern counties with the highest dew points.
warm and humid weather will be expected tonight through the start of the next work week as high pressure will remain across the area. Surface analysis early this afternoon shows broad high pressure in place from the middle Atlantic states through the Tennessee River valley. Aloft a strong ridge was in place across the plains states. Little help is available for additional forcing as high pressure remains in place at the surface.
329 AM CDT Sun Jun 30 2019 An upper ridge that extends from the Midwest to the southern Rockies will build somewhat south and east today while a weak persistent upper level inverted trough extends from east TX north to the Four State MO/AR/OK/KS region. Sfc dew points are also a little drier, especially over the higher terrain of the Ozarks, so no heat headlines are expected, but will mention 90s to near 100 deg afternoon heat index values in the HWO.