Aikyam-Lab/Synoptic-Bench huggingface dataset:
The environment is expected to become increasingly conducive for tropical cyclone formation. Light to gentle northeast to east flow will continue today into tomorrow as a high pressure holds across the eastern United States and Gulf of Mexico. Winds will relax beginning Thursday as the ridge retreats northward, and light winds are expected into the weekend. MVFR or lower conditions are possible for EYW this afternoon, when SHRA or TSRA may develop along the Lower Keys.
Return flow associated with a high pressure area will allow a surge of moisture to spread northeast into the area overnight. The higher forecast amounts exceed 1. Highs should be near to a little above normal during this period given the proximity of the upper level ridge. Contd with just shra/vcsh in tafs as cloud cover and encounter with upr ridge over ern U.
206 AM MDT WED AUG 24 2016 Upper trough covers the western 2/3 of the ConUS, as upper low spins over southern SK. Cooler and moist air will push into the region today and tonight as the trough swings through the northern plains. Highs will be in the 70s, warmer across central SD. Upper low/trough will diminish into westerly flow as it shifts eastward out of the region Thursday. Chances for precip will increase from west to east beginning early Thursday as another trough approaches the area.
148 AM MDT WED AUG 24 2016 An upper level low pressure center currently located over north central Arizona is generating showers and thunderstorms in the four corners area. This low and its associated moisture is forecast to move northeast tonight into the Colorado front range. For the afternoon hours the low and its moisture are expected to move slowly east continuing the chance for showers and thunderstorms for much of the area. Low temperatures tonight in the low to mid 50s for far eastern Colorado with mid 50s to low 60s east of the border. At the start of the period, upper level high pressure continues over the southeastern CONUS while a trough enters the northern Plains, bringing southwesterly flow aloft to the region.
Large scale forcing associated with this Rockies short wave is expected to spread into Iowa during the afternoon coincident with the H85/H7 trough. The surface front may not be too far removed from the trough over southern Iowa resulting in more than adequate vertical motion to trigger another round of convection.
402 AM MDT WED AUG 24 2016 Upper level trough will work slowly east across the state today, although best lift will be pushing to our northeast by afternoon. The low levels are still quite dry per the latest observations with the cloud deck ranging from 15-17 thousand feet MSL. Precipitation intensity has decreased so just a dusting to 1" possible over the higher peaks yet this morning. Some of the showers and storms that develop over the high country will have a chance to drift southeast onto the nearby plains and I-25 corridor depending on amount of heating behind this morning's wave. Highs today will be much cooler with the clouds and cooler air aloft across the forecast area.
400 AM EDT Wed Aug 24 2016 High pressure remains over the region through Thursday.
The models are in good agreement that the upper level ridge builds to 596-597dam and centered just immediately to our west. A very weak vorticity axis rides around the periphery of the ridge but is weak. Once again, soundings do not indicate the potential of anything beyond a general thunderstorm and this is further enhanced by the lower overall convergence and lack of a significant gradient in mass fields moving in from the east.
631 AM EDT WED AUG 24 2016 High pressure will gradually sink to the south of New England today allowing for warmer than normal temperatures on a southwesterly wind.
Am expecting a quiet night with possibly some very light patchy fog from ALI to VCT due to the dry airmass aloft combined with sfc dewpoints increasing into the lower to mid 70s overnight.
Temps should be warmer today with above normal expected over the southern half of the area.
The influence of an upper level ridge will likely keep hindering potential for strong thunderstorms to develop as temps aloft remain warmer than normal. Sfc analysis show a cold front boundary just east of northern Florida, with model solutions slowly pushing it southward and into the state northwest corner during the next couple of days.
An upper anticyclone within the subtropical ridge will gradually shift from the Gulf Coast to the Mid-Atlantic region during the forecast period. At the same time, near full latitude ridging over the eastern Pacific will slowly drift westward. A positively tilted trough will remain between the ridges and extend from the Hudson Bay region to the West Coast for the first half of the period, before weakening away later in the period.
A broad upper ridge is centered from the central Gulf Coast north through Appalachian Mountains this morning, while an upper trough resides over southern Saskatchewan province and Northern Rockies. This pattern will for the most part hold steady today and into Thursday, though the Canadian trough will move east towards the Great Lakes by Thursday evening. weakening the ridge over the Gulf Coast as it does so. Dewpoints at 3 am this morning were in the low to mid 70s throughout the forecast area, and expect low temperatures around daybreak to be only in the mid 70s. The ridge will be sufficiently strong to produce low to possibly mid 90s for highs today. But with the ridge weakening on Thursday, scattered afternoon convection will almost certainly develop.
To our east, the upper level high over the southeastern CONUS will weaken slightly today and tonight. To our west, the upper trough currently over western New Mexico will move slowly east today, and will shear out somewhat as it lifts northeast tonight. The upper high will be the prevailing influence for our area. With the approach of the aforementioned trough, showers and thunderstorms will develop this afternoon and evening across the Trans-Pecos and Permian Basin areas into parts of northwest Texas this afternoon and evening.
The front will attempt to cross into Kentucky but is expected to weaken and fall apart as it runs into a dominate upper ridge in place over the southeastern CONUS. In fact, the upper ridge is expected to reinforce itself over Kentucky Thursday afternoon, limiting any shower activity to the northern and eastern counties during the morning hours.
At the surface, a trough of low pressure extended from southeast Colorado, across central Kansas, and north toward the Canadian border. Aloft, an upper level trough is progressing slowly east from the Four Corners region. It is this trough of low pressure that will bring the Tri-State Region precipitation chances today. For today through tonight, an upper level disturbance is forecast to move across the High Plains. A quiet weather day appears in store for tomorrow in the wake of today's passing upper level trough.
Shear still on the lower end of the severe spectrum, however amount of instability should still warrant decent chance for stronger storms especially the threat of damaging winds.
432 AM EDT WED AUG 24 2016 A broad ridge at the upper levels extends across the eastern CONUS in addition to the Florida peninsula.
144 AM EDT WED AUG 24 2016 High pressure over the region will slide offshore through Thursday.
High temperatures for tomorrow also increased slightly closer to those observed today in the lower to mid 90s. Subtropical Ridge remains centered over the Southeastern states with a drier and subsident airmass over South Central Texas. Could see a streamer shower or thunderstorm along the highway 77 corridor in the far eastern part of our area where moisture is slightly deeper on Wednesday with no chances elsewhere.
Not much of an increase in low level moisture tonight however expect more mixing which will hold temperatures up warmer than last night. Cold front still in the western dakotas late in the afternoon so convective initiation should be west of the forecast area. Clouds will have an impact on temperatures however with warmer start max temperatures should be a few degrees warmer if we get enough sun. Convection will propagate east tomorrow night ahead of approaching cold front. Temperatures will be mild as thermal ridge axis shifts over the fa overnight.
Temperatures will trend noticeably warmer through mid week with most areas likely hitting 80 degrees for the first time this month heading into the holiday weekend. Temperatures should get a little warmer than today, but still remain below normal for late May. Expect a decreasing trend in shower activity tomorrow night from northwest to southeast, as upper low sinks south of Pa. Evolution of the slowly filling upper low will be the main focus early in the period.
741 PM EDT SAT MAY 21 2016 Low pressure will move further away from the area tonight. High pressure will build in through the first part of the week, bringing drier conditions with warming temperatures. Slow clearing in the western part of the forecast area overnight, with the east still being influenced by the upper low and associated energy. The upper low becomes more broad but continues to pull slowly east as an area of high pressure works into the west. Period begins with a H5 ridge over the lower Ohio Valley, which extends up into the Great Lakes.
This combination will continue through this evening and Sunday as the upper ridge slowly shifts east over the region.
On Sunday, high pressure will continue to provide mainly sunny skies. High temperatures will top out in the lower and mid 80s. With diurnal mixing, the dew points will once again fall into the lower and mid-30s.
Otherwise due to high pressure and a dry airmass over the area.
1131 PM CDT SAT MAY 21 2016 High pressure stretching from the Upper Midwest all the way to the Gulf Coast will continue to control our weather tonight and Sunday. Don't see any reason we won't cool down to near dewpoint temperatures in the low to mid 50s. Ridge axis will drift east of the CWFA Sunday which will allow weak warm advection to begin. Strong insolation along with the weak warm advection will likely push temperatures up at least into the low 80s. Ridge will continue moving east Sunday night with low level flow increasing from the south- southwest. Lows Sunday night will likely be a bit warmer than Sunday morning's lows due to the warmer start to the evening and the continuing weak warm advection.
/issued 404 PM CDT SAT MAY 21 2016/ A ridge of high pressure continues to dominate the weather pattern across the region, giving way to a Mostly sunny/Partly cloudy day across the region today with temps in the 80s. The ridge will begin to flatten on Sunday, and a weak disturbance will move near the region bringing a slight chance of showers and thunderstorms to portions of East Texas.
757 PM EDT SAT MAY 21 2016 Low pressure over West Virginia will move to the east coast tonight. A weak cold front over the northern Great Lakes will drop across the area on Sunday.
It will also be cooler this weekend with below average temperatures persisting through most of the week. Water vapor imagery and 22/00Z upper-air plots show a ridge axis over the center of the nation, while a large low pressure system resides over the Pacific Northwest and into the Great Basin. As of 03Z (8 PM MST), temperatures across the region ranged from the lower 70s to the lower 80s, with the Tucson Intl airport reporting a temp of 81 degs.
An upper level low over Northern California will bring continued cooling to the area tonight.
933 PM EDT SAT MAY 21 2016 Low pressure near the mouth of the Chesapeake Bay will move northeast toward the Canadian Maritimes through Sunday.
Warmer conditions will also follow for much of the upcoming week.
Closed low at 500 mb was over Oregon. a ridge was over mid America and another trough was over the eastern part of the CONUS. Will keep some low pops going Sunday evening but things look better after midnight as cold front moves eastward.
615 PM CDT SAT MAY 21 2016 Quiet weather expected tonight as high pressure, at the surface and aloft builds into the region. A few of our more favored cold spots may drop into the upper 40s by Sunday morning with most of the forecast area seeing early morning lows in the lower 50s.
Upper low partially driving this, over oregon will drift into southern alberta Sunday. A cooler day is expected with highs in the 60s west to mid 70s east.
A cold front is slowly moving through the southern half of the state this afternoon.
Still pretty dry in the lowest levels /the 00Z KABR sounding indicates 850 mb dewpoint depressions at approximately 20 C/.
In other words, the upper ridge is going to remain in place, and other than some modification of the current airmass, there will be very little change between today and Sunday. I have kept a wide diurnal range going with lows in the upper 40s to lower 50s tonight, swinging upward to the lower 80s Sunday.
High pressure has moved into the area allowing for skies to clear up nicely. High pressure moving into the area will keep winds out of the west northwest less than 15 knots for the remainder of the weekend.
The area of high pressure will continue to move east of the region tonight and sunday. A stronger southerly flow will develop sunday morning on the backside of the high. Upper level ridging will cover northwest Wisconsin Sunday night while an upper trof moves into the Northern Plains. Meanwhile, a frontal boundary will occur in the vicinity of the upper trof.
Cold front was still moving through counties further east and Watch continues there. Convection-allowing models lifted the western line of storms N through the afternoon, then formed other storms around Rosebud/Custer Counties during the evening as a cold front moves E through the area. Cannot rule out other strong storms east of KBIL in the Rosebud/Custer County area as the system/s cold front makes it/s way E into this area by 03z. Once area of storms becomes established, it should move quickly E with the cold front. The upper low will move E along the Canadian border Sun.
The large scale flow across the CONUS is highly amplified with a deep trough centered over the intermountain West, a sharp ridge over the Plains, and another trough over the East. The forecast area is currently dominated by dry northerly upper flow downstream from the Plains ridge. Went with the ADJMETBC guidance which was slightly warmer than the MWET/MAV guidance for highs on Sunday. Not surprisingly considering the sharp upper ridge now just west of the area, the overall trend of the models was to slow the eastward advance of precipitation.
Eastward shifting ridge and mid-level height falls impinging on the area may be enough for convection to sustain overnight. This raises concern for some advection fog later tonight as well in addition to the low stratus. Most of the forecast soundings still show evidence of ridging/subsidence for most of the night, but the eastward progression of the ridge may be enough for some activity late especially in the southeast Texas Panhandle where the WAA signal is maximized. Troughing to our west continues through mid-week before accelerating eastward toward the Panhandles by the end of the week.
Upper ridging building across the Upper MS Valley and sfc ridging drifting eastward across Upper MI will bring clear skies with a few passing high clouds and afternoon inland cumulus through Sunday.
Low temperatures are generally expected to range from the lower 60s across the northern areas to upper 60s along the coast and southeast Big Bend.
Light northwest to north winds will become prevalent this evening through Sunday as high pressure builds from the Mississippi Valley to the Gulf of Mexico. Clear to mostly clear skies tonight will create a little cooler early morning temperatures Sunday than today. Deep layer northerly winds and weak cold air advection aloft will keep forecast dry through tomorrow and help cap daytime high temperatures, a little cooler than today at most sites.
(Issued 218 PM CDT SAT MAY 21 2016) The 19z surface analysis indicated that the secondary cold front was moving through the forecast area with mid to upper 50s dewpoints already advecting southward through southern middle Tennessee.
/issued 142 PM CDT SAT MAY 21 2016/ The upper ridge over Oklahoma will drift east tonight opening the way for multi-day influence of a slowly-moving, large upper level trough over the western U. Further, showers and thunderstorms may develop early sunday over northwest texas when a weak upper low passes through the upper ridge.
An upper ridge will remain over the area Sunday resulting in one more dry day before southwest upper flow develops ahead of the western U. upper trough.
Recent PV analysis, real-time data, forecast model soundings and computer simulations suggest that relatively dry southwesterly upper flow will prevail over the majority of the forecast district into Sunday, with the far eastern plains having the highest potential of experiencing storm activity(some potentially severe) into this evening and then again from later Sunday into Sunday evening.
913 PM EDT SAT MAY 21 2016 A cold front crossing the Midlands this evening will move offshore during the early morning hours. Dry high pressure will build into the region behind the front through midweek. A cold front crossing the Midlands this evening will move offshore during the early morning hours. Ahead of the front dewpoints were in the low to mid 60s with PWAT around 1. Once the cold front moves east of the area. Omega block over the CONUS will begin to break down with upper low over the Northeastern states to Mid Atlantic/Carolina shifting off the eastern seaboard. Upper ridge in the midwest moving slowly east. Several short waves rotating around upper low may be trigger for convection.
Diurnal cumulus on Sunday should remain generally SCT as dry air works into area from high pressure to the north. Winds will also diminish quickly with the loss of daytime heating as this high edges south and the pressure gradient slackens. Highly amplified and slowly evolving longwave pattern will nudge east over the next 12 hours as the cyclonic gyre over the lower great lakes ingests additional energy diving out of Ontario tonight and closes off over the northern Appalachians. The exception will be the Thumb region where marine-modified air will limit mixing depths and therefore limit highs to the low to mid 60s.
527 PM MDT SAT MAY 21 2016 Strong to severe thunderstorms are still expected this afternoon and evening, mainly across the high plains of southeast Wyoming into the far western Nebraska panhandle. SPC Mesoscale Analysis shows 35-45 knots of effective bulk shear, mainly due to considerable veering in the lowest 3 km. Strong upper low will sweep over the CWA Sunday along w/the surface fropa. Slightly cooler temperatures and drier low-levels are expected to limit instability enough so that severe weather will not be a major concern; however, with a 40-50 kt 500 hpa jet overhead, a stronger storm is definitely possible. Cooler.
Cooler than average conditions will continue Sunday with the most concentrated precipitation expected over the Idaho Panhandle. The upper level low is making its move out of northeast OR and is progged to shift into southern Alberta by Sunday morning. Moisture will continue to wrap around the low into the northeast portion of the region mainly across the Northeast Mtns over into the central to northern Panhandle.
Convection-allowing models lifted the western line of storms N through the afternoon, then formed other storms around Rosebud/Custer Counties during the evening as a cold front moves E through the area. Cannot rule out other strong storms east of KBIL in the Rosebud/Custer County area as the system/s cold front makes it/s way E into this area by 03z. Once area of storms becomes established, it should move quickly E with the cold front. The upper low will move E along the Canadian border Sun.
/issued 250 PM CDT SAT MAY 21 2016/ WV imagery shows West Texas and Southeast New Mexico sitting under an upper-lvl ridge between two systems, one over the Great lakes region, and the other over eastern OR. East of the dryline, sfc analysis shows a ridge of cape in excess of 3000J/kg extending from LBBB-K6R6, w/radar showing convection developing over the Davis Mtns.
Temperatures are settling downwards through the lower 80s, with dew point temperatures in the mid 70s.
Low pressure has finally pushed just east of the appalachians this evening.
Upper low center is drifting eastward this evening. Showers and isolated thunderstorms continue to circulate the low, though as with previous nights, the thunderstorm threat will diminish and coverage of showers will refocus close to the low center overnight. Energy circulating the low is expected to enter southeast Oregon early Sunday, increasing precipitation chances across Harney county after midnight. Isolated to scattered showers at lower elevations, and widespread showers over the higher terrain, will continue through Sunday.
Clear to mostly clear skies tonight will create a little cooler early morning temperatures Sunday than today. Deep layer northerly winds and weak cold air advection aloft will keep forecast dry through tomorrow and help cap daytime high temperatures, a little cooler than today at most sites.
Quiet weather expected tonight as high pressure, at the surface and aloft builds into the region. A few of our more favored cold spots may drop into the upper 40s by Sunday morning with most of the forecast area seeing early morning lows in the lower 50s.
mainly south of a line from TYR to OCH to the lower Toledo Bend Reservoir.
Low pressure off to our east will continue to move east the rest of the weekend, which will allow high pressure to build over the middle Mississippi Valley.
1100 PM EDT SAT MAY 21 2016 Low pressure over West Virginia will move to the east coast tonight. A weak cold front over the northern Great Lakes will drop across the area on Sunday.
622 PM CDT SAT MAY 21 2016 High pressure stretching from the Upper Midwest all the way to the Gulf Coast will continue to control our weather tonight and Sunday. Don't see any reason we won't cool down to near dewpoint temperatures in the low to mid 50s. Ridge axis will drift east of the CWFA Sunday which will allow weak warm advection to begin. Strong insolation along with the weak warm advection will likely push temperatures up at least into the low 80s. Ridge will continue moving east Sunday night with low level flow increasing from the south- southwest. Lows Sunday night will likely be a bit warmer than Sunday morning's lows due to the warmer start to the evening and the continuing weak warm advection.
Highly amplified and slowly evolving longwave pattern will nudge east over the next 12 hours as the cyclonic gyre over the lower great lakes ingests additional energy diving out of Ontario tonight and closes off over the northern Appalachians. The exception will be the Thumb region where marine-modified air will limit mixing depths and therefore limit highs to the low to mid 60s.
Clouds over southwest in response to warm frontal precip earlier today should advect southeast with time and exit the region by 02-04z. Meanwhile Great Lakes High will drop south and gradually warmer air will return. /Sunday through Saturday/ High pressure will remain east of Iowa, placing the state in WAA/return flow. Am expecting a sunny day with temperatures a solid 5 or so degrees warmer than on Saturday. On the large-scale, longwave trough remains well-established over the intermountain west. Meanwhile, a fairly amplified trough/cut- off low will remain spinning over the east coast. Iowa will be sandwiched between these two features, and with the broad high pressure propagating towards the Great Lakes Region, southerly to southwesterly flow will be in place over Iowa for much of this week.