Aikyam-Lab/Synoptic-Bench huggingface dataset:
Push of drier air in the low/mid-levels has suppressed convection across all but the far north this afternoon as expected. Should see even this limited convection winding down by this evening with a relatively quiet night in store as the weak upper ridging remains in place.
Recent real-time data, PV analysis, computer simulations and forecast model soundings indicate that closed upper low located over west-central Colorado early this morning will slowly progress to east-central Colorado by sunset before shifting into north-central Kansas by sunrise Saturday. In addition, expect another round of near freezing/freezing temperatures over Interstate 25 corridor locations from later tonight into early Saturday morning, however will refrain from issuing additional Freeze/Frost highlights until after current Freeze/Frost highlights expire later this morning. Upper low slowly drifts newd through the central plains Sat, leaving nw flow in place across CO through the day. With upper trough slow to exit the area Mon, and another piece of energy rotating around the central plains low and across CO on Tue, suspect we'll keep afternoon/evening -shra/-tsra chances in place across most of the region both days, though again strong storms look unlikely.
346 PM MDT Fri May 19 2017 Record-breaking spring storm is finally easing across the area as a broad upper level low is drifting eastward across northern Colorado this afternoon. Still getting bands of rain or rain/snow mix over the high plains, mainly due to some llvl convergence and jet dynamics, but do not expect this activity to amount to much over the next 6 to 12 hours into tonight with mainly bands of light rain. Highs will remain below normal, but should still be 10 to 15 degrees warmer compared to the last few days.
536 PM EDT Fri May 19 2017 A cold front will move south of the region early this evening. High pressure then builds in for the weekend.
The upper low will move out over the High Plains of eastern Colorado this afternoon and over western Kansas this evening. Flow around this low will keep rich low level moisture in place across the Rolling Plains but dry air across the western counties. Convection is already underway to our south along a retreating dryline that is likely being helped with mid level cooling aloft from the approaching upper low. Additional convective initiation is possible later this morning as the cold front moves into the richer moisture of the southeast Panhandle, although the hi-res models are less bullish with this idea. Much cooler air will filter in behind the front tonight with temperatures expected to be below normal Saturday afternoon. The next precip maker will be a short wave trough moving southeastward on the backside of a building West Coast upper ridge.
Large upper low currently over Colorado will shift into the central Plains by early Saturday, then lift northeast to near the Iowa/Minnesota border by mid evening. The GFS brings CAPE values over 1200 J/kg over all of the forecast area by early afternoon, while the NAM limits the higher values mainly across eastern Illinois.
The 11 am surface analysis showed an area of high pressure across much of the Southeast. Given the likelihood of the CS currently over our forecast area persisting through the day, we nudged the high temperature forecast down a degree or two.
Rain continues through most of the night as upper low continues to slowly move out of the central Rockies placing most of the forecast area in a favorable diffluent flow aloft pattern.
200 PM EDT Fri May 19 2017 High pressure building south across the area will bring cooler and drier air to start the weekend.
Temperatures a challenge as areas in rain more of the day will stay in the 40s vs warmer mid 50s in non-rain areas with some low 60s in far NW fcst area. Upper low to move into central Minnesota Saturday night.
Water vapor imagery shows deep upper low spinning over southern CO/northeast NM. We are also seeing additional convection over western KS, closer to the upper low where mid level lapse rates are maximized with this activity possibly affecting central/south central KS later this afternoon into the early evening hours. By 12z Sat, the upper low will be lifting over southwest Nebraska with the cold front extending through the Ozark region into the Arklatex area. There is a slight chance for some light showers Tue, in the wrap around region of an upper low off to our east, but confidence is low in this panning out. Widespread LIFR/IFR was observed with low cigs and visibilities in the wake of a cold front bisecting the area this morning.
401 PM CDT Fri May 19 2017 Upper level low pressure beginning to lift north this afternoon. But at this time believe that with just a bit of instability above the low level moist layer will see showery activity. Even with the fairly strong dry punch aloft through southwest MN and northwest IA to east of upper low centered near KFSD around 00z, should at a minimum have a continuation of more scattered showers or even drizzle with the shallow moist profile. Gradually the passage of negative tilt trough axis will diminish the precipitation threat from southwest to northeast, with stronger northwest winds gradually taking hold through the night.
145 PM CDT Fri May 19 2017 Water vapor imagery shows deep upper low spinning over southern CO/northeast NM. We are also seeing additional convection over western KS, closer to the upper low where mid level lapse rates are maximized with this activity possibly affecting central/south central KS later this afternoon into the early evening hours. By 12z Sat, the upper low will be lifting over southwest Nebraska with the cold front extending through the Ozark region into the Arklatex area. There is a slight chance for some light showers Tue, in the wrap around region of an upper low off to our east, but confidence is low in this panning out. Widespread LIFR/IFR was observed with low cigs and visibilities in the wake of a cold front bisecting the area this morning.
The forecast becomes progressively wetter tomorrow afternoon as the base of the Plains upper low kicks eastward, instigating more widespread lift and spreading more moisture into the region as well.
High pressure aloft will build in from the Eastern Pacific towards California this weekend. ***From previous discussion*** Synoptically, An upper level ridge of high pressure over the eastern Pac will slowly nudge eastward towards the California Coast and persist through Sat night. This will slightly weaken the upper ridging over swrn CA for the second half of the weekend.
A weak upper trough will reach the area tonight. High pressure will build into the area over the weekend.
Water vapor shows massive upper low over over wrn CO with moisture being pulled north out of the srn plains through the nrn plains. At the surface, high pressure located over nrn ND with ridge extending swwd into nern WY is stifling the nrn extent of pcpn across our cwfa. Radar return shows best area of pcpn across west central SD at this time, although some of the higher returns are bright banding. Upper low expected to drift slowly ewd through CO today.
The main limiting factor to these storms is the low CAPE due to previous convection from the night before. Hi-res guidance suggests that after this initial line of storms pushes through there will be a brief break in precipitation before more showers and thunderstorms form as the upper level trough continues to push east into the central plains. Much cooler temperatures are expected this evening, dipping down into the upper 40s in north central Kansas overnight. The upper level low center will lift across central Nebraska on Saturday.
High pressure aloft will build in from the Eastern Pacific towards California this weekend. Big warmup today for most areas under building high pressure aloft and light offshore flow. Offshore flow weakens over the weekend but the ridge will continue to expand over the area.
This low and vort max will slowly lift into Neb by dawn and cross the state tomorrow. Sat: Plenty of clds with the upr trof remaining overhead.
Temperatures will be a little cooler than previous nights, but still above normal. 500 mb heights start to rise again Saturday over our area in response to a trough moving into the Mississippi Valley. This will start to push the boundary north again as a warm front.
314 PM EDT Fri May 19 2017 A cold front will slide southeast across the state today. Cooler and drier air will follow for the weekend.
322 PM CDT Fri May 19 2017 The upper level low continues to slowly make its way toward our area, bringing us the potential for a couple rounds of storms. A cold front will move through behind the convection, cooling temperatures into the 60s and 70s for the rest of the weekend.
Did add a mention of isolated afternoon showers in this area, and over the higher peaks of the Wallowas. Strong upper level ridge will dominate the weather pattern for the extended. This will provide much warmer temperatures with highs in the 80s. The ridge will be centered over the Pacific northwest Mon and Tue with mainly clear skies. As the ridge axis shifts east Wed and Thu instability will increase as the flow aloft becomes southwest.
426 PM EDT Fri May 19 2017 Scattered showers and isolated storms are expected to continue this evening along a slowly northward moving warm front. For the weekend, showers and some thunderstorms return for the weekend as a low pressure system approaching from the west. The best chance for rainfall will be Saturday afternoon into the Saturday night hours as a cold front approaches. Otherwise little chance for convection overnight, initially far south on northern periphery of richer theta-e, then to far western/southwest CWA early morning as deep central Rockies cyclone begins to liftout northeast into Plains.
531 PM EDT Fri May 19 2017 A cold front will slide southeast across the state today. Cooler and drier air will follow for the weekend.
A broad mid- to upper- level trough will build over the eastern Rocky Mountain states and ascend into the region overnight and during the day Saturday. This inverted trough will bring a tightening sfc pressure gradient, so winds could be a bit breezy as well, with gusts between 20 and 30 mph adjacent to Lake Superior. These winds will also be easterly, so cooler temperatures by the lake are expected. A cool and wet weekend on tap before a slow rise to warmer temperatures with occasional chances for light precipitation through the work week.
Expectations of lowering and thickening of clouds across the James River Valley late tonight as the upper low moves into South Dakota, with increasing chances for showers during the day Saturday. The latest water vapor imagery loop shows an upper low over central Colorado which is forecast to move northeast through the short term period.
It's far more probable that the area of low pressure lifting out of Colorado will overcome this dry air to produce some widespread measurable by Saturday morning over the eastern half of South Dakota, including this CWA.
There are some cells along the high elevations of the Upper Cumberland, and near our northwest counties.
436 PM CDT Fri May 19 2017 Tonight through Saturday night, An active weather pattern will take shape this weekend over the ArkLaMiss as a powerful trough over the Plains/Midwest shifts eastward and helps to break down the ridge currently centered over the Southeast. Initial thunderstorm development should begin by late morning and be somewhat disorganized due to relatively weak deep layer shear and low level flow only 15 to 20 kts, but as the trough axis and cold front approach late Saturday, the larger scale lift may help to organize storms resulting in great storm coverage.
300 PM MDT Fri May 19 2017 An upper level low will continue tracking slowly east-northeast acrs CO this evening and is forecast to move into south central NE by 12Z Sat. As temps cool this evening, some of the lower elevation showers may change over to snow, but little if any accumulation is expected. By late night, as the low moves east of the area, pcpn will end in most if not all locations, and clouds will decrease from west to east. Temps will be warmer on Sat but will still generally be about 10 degrees below average.
308 PM CDT Fri May 19 2017 (Tonight and Saturday) An upper low now centered over Colorado this afternoon will lift northeast over the Central Plains by Saturday afternoon. A cold front will push south through the Big Country tonight and through the remainder of the forecast area by noon tomorrow. Lows tonight will be in the mid to upper 50s across the northern half of the area as the cold front moves through. The southern half of the area will see lows in the morning in the low to mid 60s. (Saturday night through next Friday) As the upper low lifts further to the northeast and over the Great Lakes area, the upper flow over the forecast will be zonal.
There is better QG forcing, stronger Theta-E advection and moisture convergence located over central to southeast portions of the forecast area and have the highest QPF going in this location. Some chance for brief heavy rain producers and thus reasoning why the southeast has the higher QPF. By late Saturday morning, dry air begins to entrain into southern Iowa as the low tracks across southern Iowa. The only exception would be in the far southeast if the low tracks slightly further northwest like the ECMWF suggests.
1244 PM MST Fri May 19 2017 Broad area of low pressure will begin to exit the region today, keeping below normal temperatures in place across the lower deserts.
The upper low lifts northeast into the central plains tonight and Saturday.
The line should die as it approaches the Mississippi River due to the strength of the upper level ridge. Additional development will occur ahead of an approaching cold front that will move into Northeast Arkansas during the afternoon hours.
Upper trough over the Rockies today will drift east while a couple of disturbances drop into northeast Montana on NW flow over the weekend.
It will be humid tonight with low temperatures in the lower 70s.
Raised pops to likely near and northwest of a Sullivan to Indianapolis to Fishers line as east central Illinois broken line of thunderstorms has held together and should continue to do so despite what the High Resolution Rapid Refresh was showing. With the stalled front projected to shift north again as a warm front, think warmer overall temperatures are necessary, and a guidance consensus served this purpose well. An upper low over the intermountain west will move northeast through nebraska and into the Great Lakes region through the short term. These will interact with a stalled surface front (trapped between the aforementioned upper low and a ridge of high pressure over the eastern U. At this point the best forcing appears to be associated with the cold frontal passage Saturday night.
Brusda Drier conditions will persist through the morning hours today as weak ridging develops to the west.
335 PM EDT Fri May 19 2017 High pressure in Canada will slowly build into the area through the weekend.
122 PM EDT Fri May 19 2017 Cold front will push across the area today, scattered rain showers are expected this morning. Much cooler and drier weather arrives by midday with some patchy frost possible overnight.
Short Term (Now through Saturday Night): Upper low over the Rockies today will continue to lift northeast through Saturday night. Associated cold front currently draped across the Panhandle will slowly progress east southeast across the state tonight through Saturday night, making it into South Texas, but likely not making it into the Ranchlands. Above normal temperatures continue Saturday with highs slightly cooler than today, especially out west, where cloud cover will be greater.
319 PM EDT Fri May 19 2017 As a cold front exits the region tonight, high pressure will build into the North Country providing sunny skies and seasonal temperatures through the weekend.
KDHT has cleared the low clouds with KAMA following within the hour. /Issued 255 AM CDT Fri May 19 2017/ A closed upper level low over Colorado had a vort max in the base of its circulation moving east across eastern Arizona. A cold front was pushing south across the east central and southeast Texas Panhandle. This cold front should move southeast of the CWA by sunrise. Therefore, will keep the highest pops across this region. Will also keep some lower pops elsewhere given the increase in upper level diffluence and the close proximity of the cold front. The panhandles will be under a northwest flow aloft through the rest of the forecast as a ridge builds across the western U. and a trough gets carved out across the eastern U.
Clearing clouds have allowed temperatures to warm to values ranging from the lower to mid 80s over the southern Rolling Plains south of a stalled out cold front. Ample low level moisture was still in place with surface dew points in the lower 60s. The stalled out cold front will make a stronger push through the region tonight. The upper low currently spinning over Colorado will move out onto the Plains on Saturday but cooler and drier surface air will filter in behind the front.
331 PM EDT Fri May 19 2017 High pressure will prevail into Saturday.
The sfc cold front will eventually be positioned near the TN River Valley Region by 12Z Sun, and then push across the mid state as Sun into Sun night progresses. As the cold front moves across the mid state region on Sun, a CAA pattern will initially begin with highs returning back to at or slightly below seasonal normal values in the mid to upper 70s. as a weak cold front moves across the region. Broad upper level troughing influences will usher in sct light shwrs and iso tstms Tue night, with overall more stability anticipated in the atm during the day on Wed, sct light shwrs will prevail. Quasi upper level ridging influences should keep the mid state dry on Fri.
Other widely scattered showers and a few storms are developing mainly north of a cold front in northwest Oklahoma. Overall the risk of strong to severe storms will continue into the evening, perhaps overnight, before a cold front sweeps across southern Oklahoma by early Saturday morning.
155 PM EDT Fri May 19 2017 High pressure will maintain dry weather and above normal temperatures through Saturday. Shower and thunderstorm chances will increase by late weekend as moisture builds ahead of an approaching cold front.
Showers and thunderstorms will briefly increase in coverage mid afternoon across all of western Kansas as an upper jet and associated upper level trough crosses into southwest Kansas. These storms will then move east early this evening as the upper jet lifts northeast and an upper level trough crosses western Kansas. A northwesterly flow will develop early this weekend across the Rockies and the central Plains as an upper low moves northeast into the Western Great Lakes region, and an upper level ridge axis builds into the Pacific Northwest.
High pressure stretched across south central Canada will continue to circulate dry and cool air into northern Michigan through tonight.
313 PM CDT Fri May 19 2017 Slow moving upper low is centered in far southeast Colorado late this afternoon. Short-term; Hi-Res models insist this low will track toward the northeast and be centered south of Lexington near the NE/KS border by early Saturday morning. NAM and 4KM NAM very slowly lift the upper low northward across the forecast area Saturday. The broad mid-level trough will be over the western and central CONUS (inland from the West Coast) at the start of the period with a closed 500 hPa low over the Middle Missouri Valley.
1238 PM CDT Fri May 19 2017 An extremely complicated forecast going forward today as well- advertised upper low spins across the Four Corners region. Despite the presence of these combined forcing mechanisms, degree of destabilization remains in question this morning (persistent cloud cover) along with concerns for deep layer shear as numerous BUFKIT forecast soundings reveal a very chaotic wind field pattern through the lowest 10-15 kft. Heaviest axis of rain will likely be along the highway 50 and I-70 corridors with the soils primed for possible flash flooding. Rains should gradually come to an end through the day on Saturday as cool high pressure settles into the Plains/Lower Missouri Vly.
226 PM MDT Fri May 19 2017 Deep closed low over the Rockies continues to slowly shift NE, ejecting small impulses in the processes. However, clouds will hang on most if not all areas and will limit temp falls below freezing on most if not all of the plains.
Dry northeast flow with surface dewpoints in the lower to mid 30s across the forecast area will work against the northward progression of these showers and storms, but still expect to see accumulating rain to near the I-90 corridor before activity begins to dissipate late this morning and into the afternoon.
300 PM EDT Fri May 19 2017 Cold front will push across the area today, scattered rain showers are expected this morning. Much cooler and drier weather arrives by midday with some patchy frost possible overnight.
Although upper ridge will continue its influence over most of the area.
200 PM EDT Fri May 19 2017 A cold front sinks southward into the area today, only to retreat back northward on Saturday.
An upper system and cold front will push across AR and develop the convection, some strong to severe, then gradually push it east toward Friday morning. Winds will start from the south at 5 to 15 mph or variable, then winds will shift to the west to Northwest at 5 to 15 mph behind the cold front.
Low level ridge shifted south across the north central Gulf of Mexico this afternoon which helped tighten the gradient and produced a stronger westerly flow. Considerable high clouds will continue to stream into the area around a large mid/upper ridge over the area.
1043 PM EDT Thu May 11 2017 A weak area of low pressure will drift south of the region tonight.
748 PM EDT Thu May 11 2017 High pressure over the Southeastern United States will slowly move east into the Western Atlantic Waters through Friday. The very warm to hot conditions along with mostly clear skies will allow for the humidities to fall again down into the lower to mid 30s over the interior areas for Friday afternoon. High pressure will continue to dominate the weather across the region for tonight and into Friday. /issued 324 PM EDT Thu May 11 2017/ Rest of Today and Tonight: High pressure continues to dominate across South Florida with dry conditions and warm temperatures with highs today around 90 degrees.
535 PM MDT Thu May 11 2017 Latest analysis shows a high amplitude upper ridge building in from the west.
There is some suggestion of a pseudo-split in the activity, with one separate band along the LLJ axis at 850 mb moving thru central MS into central AL while the other clusters of convection ride near the 850 mb and surface boundary across the lower OH Valley well to our north. Morning convection may limit the extent and strength of progged afternoon and evening development along the cold front.
A second band of storms is developing along the cold front in Western Arkansas and into Southeast Oklahoma. Southern portions of this cold front can also be seen on regional radar mosiacs to the east and southeast of the DFW Metroplex.
Additional SHRA/TSRA have developed along/near a cold front west of ktyr, which prompts the continuance of a -RA VCTS mention for a few hours. Have tried to time the convection with this TAF cycle at each site, trying to take into consideration additional precip development along the cold front. A second band of storms is developing along the cold front in Western Arkansas and into Southeast Oklahoma. Southern portions of this cold front can also be seen on regional radar mosiacs to the east and southeast of the DFW Metroplex.