Aikyam-Lab/Synoptic-Bench huggingface dataset:
Then another area of precip should lift N out of AR thru the day as the lows pass just S of the CWA and then pivot across the SErn FA drng the aftn. The highest PoPs this mrng are across cntrl and NE MO as well as SE MO and then the focus on SE MO and sthrn IL for this aftn. Tonight will be cooler than the past two nights but still above normal with lows in the 30s which is closer to typical daytime highs for mid/late Jan. A deep long wave trof over the western U.
Low pressure will track just south of the Ohio River Valley.
An upper closed low over northeast Texas this morning will continue to track rapidly eastward as upper ridging builds over the forecast area from the west. Otherwise, expect mostly sunny skies with afternoon highs in the low to mid 60s.
Breezier surface winds of 15-20 MPH/gusts to 30 MPH were being observed in association with the low-level jet wind field, overall much lighter toward the north. Large hail and damaging winds are on the table, with a developing tornado risk as well once the low-level jet advances into the area. The highest tornado concern is across the southeastern counties where jet shear will be the highest, with supporting higher-value dew points advecting farther north with time. A warm front is expected to push northward some from the coast tonight ahead of another round of showers and thunderstorms.
North of the track of the low (KPNC, KWWR, KGAG), winds will shift gradually from NE to NNW by tomorrow afternoon, and speeds will increase gradually as the low moves away to the east. South of the low, winds will be mainly variable overnight, then turn NW by morning, and increase in speed. Low pressure, centered over the Texas Panhandle at 22/0000Z, will move almost directly east overnight. This second area is associated with the upper low over northern NM that is expected to move quickly southeast along the Red River early Sunday.
1126 PM CST Sat Jan 21 2017 Most of the latest short term guidance suggests perhaps a little better chance for southern Kansas to be impacted on the north edge of the upper low which will track east across the southern Plains overnight. Some mid-level convergence develops toward midnight across south central Kansas which may give a bit better support for some light rain or rain showers overnight as the zone of deformation north of the upper low moves east across the area. Low pops will linger into early Sunday over Southeast KS before large-scale forcing for subsidence arrives across the area in the wake of the trough bringing a rapid demise to any lingering light rain showers. A mid/upper ridge is progged to build over the central Conus early in the week supporting above normal temperatures across the area.
Mid level low pressure system centered over northwest Wisconsin will drift over Lake Superior today before lifting north of Lake Superior tonight. Radars show weak returns rotating around this low for a few light showers, otherwise expect mainly drizzle in this moist air mass. Anticipate weak northwest winds in the wake of A weak cold front will provide some mixing to lesson the widespread fog by noon. Its possible eastern Wisconsin may hang onto the dense fog longer this afternoon in an area of weak troughing. Another upper low system lifting into the Ohio Valley region and parts of Lower Michigan may produce some light precipitation across far eastern Wisconsin on Monday. Will keep small precipitation chances going over the east due to persistent weak troughing over Lake Michigan extending to the Ohio Valley system.
Either way, like the past few days, temps won't budge much with lows tonight in the low to mid 30s and highs Sunday in the mid 30s to low 40s. Weak surface ridging builds into the area Sunday night and Monday. Although NAM soundings suggest the depth of moist layer will decrease on Monday, it still may be tough to scour out the low clouds/fog.
Weak ridging remained over eastern KS. Lows tonight should range from the lower 30s north where skies may remain clearer longer, to the lower 40s across east central KS expecting clouds to keep temps from falling to far. Some low level cold air advection is anticipated on the back side of the system so temps should be cooler than today. Have highs in the lower 40s across northeast KS where fog and stratus are possible to near 50 in central KS. Upper ridge building east into the Plains brings clearing skies Sunday night. Warm air advection increases from the mid to the lower levels late Monday into Monday night, though still dry through the bulk of the troposphere so no precip anticipated.
The former will evolve into an intense trough and associated closed low as it translates through the southeastern States today. In it's wake, a mid-level ridge will build over the Rockies today before shifting east into the Great Plains tonight into Monday. In the low levels, winds will become decidedly northerly today, allowing for some low clouds and a cooler air mass to settle into the area, especially along and east of the MO River. Strengthening low-level warm advection on the backside of the high should allow for slight warming of the air mass with Monday's highs rebounding into the 40s.
320 AM CST Sun Jan 22 2017 Persistent stratus will continue to blanket much of the forecast area today, in the wake of slowly departing upper low. Lack of mid level/ice-bearing moisture layer evident on satellite and in forecast soundings, so drizzle/freezing drizzle should be the dominant precip type. The lack of stratus and light winds in our west should allow temperatures to fall into the lower 20s tonight, while eastern areas hold in the mid-upper 20s under the lingering stratus. As a longwave trough approaches the plains on Monday GFS/ECM are in fair agreement on strength and timing of the H5 low and associated surface features.
338 AM CST Sun Jan 22 2017 An area of low pressure over North Dakota will bring westerly winds and somewhat drier air into the CWA today. Will the low clouds and fog come back again tonight? A majority of the models suggest the fog will finally leave the CWA as much drier air moves into the region from the west. A deep trough currently off the west coast will send upper level energy into the Central Rockies by tonight. The upper level jet support will cause the development of a lee side trough over the front range of the Rockies by Monday.
344 AM CST Sun Jan 22 2017 Mid- to upper-level trough continues to translate through the Northland this morning. Still, the thermal profile continues to be very close to the 0 degree C isotherm, so precipitation types continue to be a wintry mix, including drizzle/freezing drizzle/light snow and rain. With the potential for freezing precipitation and fog already present, travel conditions will continue to be hazardous this morning. The threat of slippery roads will diminish this afternoon as temperatures increase to above freezing. Temperatures look to continue their above-freezing trend, with highs today and Monday in the mid to upper 30s. There may be some light precipitation over the Arrowhead and forecast soundings show lack of deeper moisture so freezing drizzle/drizzle will be possible.
Best instability remains central and south at this time as the warm front lingers south of Columbus to Vidalia. Main upper system will drop into the lower MS valley this afternoon and continue into the southern Appalachians tonight. The closed upper low will continue to push across the Appalachians on Monday with extensive wrap around clouds and showers through most of the day.
This approaching high pressure will result in clearing skies into central KS today but it may not extend into far eastern KS until tonight. As a result, afternoon high temperatures will range from the low/mid 40s to near 50 degrees from northeast to southwest across the CWA. With clear skies across the entire CWA tonight, expect cooler conditions with lows plunging into the mid/upper 20s. Monday remains on course to be warmer than normal with highs in the upper 40s to lower 50s and a southerly breeze.
The only thing that could provide some stronger storms is the fact that the upper level low (which is fairly strong) will swing right over Middle TN.
Most of the synoptic-scale lift associated with this feature will stay to the south of the area overnight so that the highest rain chances will stay across southern into eastern Missouri.
Periods of rain will continue tonight into Monday as an upper level low pressure system moves across the southeastern United States.
Currently the lowest visibility reported was 2. Winds are expected to increase Sunday, which should finally kick out the fog and lift some of the lowest cloud ceilings.
1032 PM MST Sat Jan 21 2017 Weak ridging to neutral flow will persist through the period with dry wx. Western CONUS troughing will promote local ridging Sunday night, with gusty sw flow developing over NE WY and portions of the Black Hills. Weak upper level ridge shifts east of the area Monday as trough over the west coast moves into the Rockies.
The exact position of the deformation field this evening still remains uncertain with the GFS a bit further northwest with the low track. The precip area should shift east of the area completely by Monday evening with a ridge quickly moving in and diminishing flow.
1209 AM EST Sun Jan 22 2017 A cold front will cross the region overnight. High pressure will build north of the area Sunday into Monday.
244 AM CST Sun Jan 22 2017 Light showers continue to track east across portions of east Texas, north Louisiana, and southern Arkansas this morning as surface and upper low exit the region. Overnight temperatures forecast to fall into lower 40s across most locations with highs on Monday forecast to climb into the lower 60s.
235 AM MST Sun Jan 22 2017 Water vapor shows weak w/sw flow aloft across the nrn plains with trof moving onto the west coast. S/SW winds increase tonight across nern WY into the Blkhls as upper ridge axis shifts overhead.
With temperatures dropping into the 20s in some locations, freezing fog mention this morning certainly with highlighting. Any fog that may form may be of the freezing fog variety as temperatures look to hover near freezing once again.
Breezier surface winds of 15-20 MPH/gusts to 30 MPH were being observed in association with the low-level jet wind field, overall much lighter toward the north. Large hail and damaging winds are on the table, with a developing tornado risk as well once the low-level jet advances into the area. The highest tornado concern is across the southeastern counties where jet shear will be the highest, with supporting higher-value dew points advecting farther north with time.
342 AM CST Sun Jan 22 2017 Upper level low currently centered over southwest OK/northwest TX with a well-defined mid level frontogenetic band extending from west central AR into northwest OK. As the low moves east roughly along the Red River today, expect zone of strongest lift to pivot north and become more focused across northwest AR into northeast OK before shifting east of the area late this afternoon. This system will quickly move east of the area by this evening with diminishing winds and clearing skies resulting in a cooler night, but still at or above normal.
Snow levels will rise given the warmer airmass and good mixing, and may at times be closer to 5000-5500ft late tomorrow afternoon through tomorrow night. Ridgelines and western valleys will likely see breezy to windy conditions as the pressure gradient tightens through tomorrow night. Cold frontal passage on Monday will shift focus more to northwest- facing slopes and upstream valleys, including the I-15 corridor. Snow amounts will be a bit limited by the mild airmass preceding the cold front, but still likely to see accumulations areawide except Dixie and Lake Powell during the Sunday through Monday timeframe.
At the surface, low pressure was located central Upper michigan. Some weak dry advection should move in later this afternoon as wrly flow develops as the low moves off to the north. With temps falling at or slightly below freezing over the west, some -fzdz may also develop. More normal conditions with cooler temps and NW wind LES are then expected through the rest of the week. Expect Northerly winds to increase to 25 kts by middle of the week as low pressure over the central Plains moves toward eastern Canada.
Air temperatures have all risen above freezing as of late afternoon, as have all available road surface temperatures. Expect both to be hovering around freezing by midnight tonight, which is going to produce new icing on area roads. A weak short wave trof will move through the forecast area Sunday night. An embedded impulse will accompany the trof and affect the area north of the Iron Range. Upper level/surface ridging build over the region on Monday morning. By afternoon, another trof moves across the area bringing a slight chance of some rain, mainly east of Highway 53 and north of the Iron Range. The upper trof departs Monday night allowing for some ridging to build in.
321 AM CST Sun Jan 22 2017 A upper level trough is moving across the Red River Valley this morning and will continue to move east across southern Arkansas today.
For today, the stacked low pressure system over Texas will move across MS/AL/GA where the bulk of showers and storms are expected to be confined. Some showers will pinwheel north of the closed low back into TN and central Kentucky but the latest guidance has really backed off on the areal coverage and amounts with these bands, and also delays precipitation moving in our area until at least the afternoon hours. Highs will reach the low/mid 60s. A deformation band of rain is forecast to setup northwest of the low center, or across central TN to central KY (along/east of I-65). It'll remain mostly cloudy to overcast and noticeably cooler with highs around 50 degrees.
ANY SIGNIFICANT CHANCE OF PRECIPITATION WILL END TONIGHT AS A COLD FRONT PUSHES THROUGH THE AREA. THE COLD FRONT WILL BE OUT OF THE FORECAST AREA WITH NO RAIN EXPECTED BEHIND THE FRONT. THE AIR BEHIND THIS COLD FRONT WILL NOT THAT MUCH COOLER SO TEMPERATURES ON FRIDAY WILL BE SIMILAR TO TODAY WITH HIGHS IN THE MID TO UPPER 70S. DRY WEATHER WILL CONTINUE INTO THE WEEKEND AS HIGH PRESSURE BUILDS IN.
TONIGHT AND FRIDAY MAIN FORECAST ISSUE TO BE ON PRECIPITATION TRENDS/SMALL THUNDER CHANCE LATE THIS AFTERNOON THROUGH THE EVENING HOURS AS A COLD FRONT DROPS SE ACROSS THE REST OF WI AND AN OLD SYSTEM PASSED BY TO OUR SOUTH. THE 19Z MSAS SURFACE ANALYSIS SHOWED SEVERAL WEAK AREAS OF LOW PRESSURE (NEAR MQT. NEAR PCZ AND NEAR DSM) WITH A COLD FRONT CONNECTING THESE LOWS. A RIDGE OF HIGH PRESSURE EXTENDED FROM CENTRAL CANADA SOUTH INTO THE NORTHERN PLAINS. THEN A DRYING TREND WILL BE NOTED AS THE RIDGE OF HIGH PRESSURE BEGINS TO BUILD TOWARD THE WESTERN GREAT LAKES. A COOLER/LESS HUMID AIR MASS TO OVERSPREAD NE WI ON FRIDAY AS THE RIDGE OF HIGH PRESSURE SETTLES OVER THE WESTERN GREAT LAKES. TEMPERATURES ARE COOLER AND WIND SPEEDS WILL GRADUALLY DIMINISH THROUGH THE DAY.
EXPECT A COOL NIGHT WITH LOWS AT OR BELOW FREEZING FOR ALL AREAS.
Late tonight as a cold front approaches, an increase in the coverage of showers and a few thunderstorms is expected across the far western portions of the area, but most of the activity is expected to hold off until after daybreak on Friday.
THE WIDESPREAD HEAVY RAIN THREAT HAS ENDED ACROSS THE REGION AND THE FLASH FLOOD WATCH HAS BEEN ALLOWED TO EXPIRED, HOWEVER A FEW SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE INTO FRIDAY MORNING AHEAD OF A WEAK COLD FRONT. SOME MVFR CEILINGS WILL DEVELOP AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH DURING THE OVERNIGHT AND EARLY FRIDAY MORNING.
/ISSUED 321 PM CDT THU APR 21 2016/ UPPER LEVEL RIDGE JUST TO THE WEST OF THE FCST AREA. ISOLATED CONVECTION ON THE NM MOUNTAINS WILL NOT MOVE FAR OFF THE HIGH TERRAIN WITH DRY NORTHEASTERLY LOW LEVEL FLOW DOWNSTREAM.
WEAK COLD FRONT CONTINUES TO SLOWLY WORK EWD ACROSS THE REGION THIS EVENING AND GENERALLY EXTENDS ALONG A LINE FROM ELD TO SHV TO LFK. /ISSUED 610 PM CDT THU APR 21 2016/ SENT A QUICK UPDATE TO ADD 20% POPS TO SW AR AND NE TX AHEAD OF A COLD FRONT THAT CONTINUES TO PUSH CLOSER TOWARDS THE I-30 CORRIDOR. /ISSUED 244 PM CDT THU APR 21 2016/ WV IMAGERY SHOWS SERIES OF DISTURBANCES ASSOCIATED WITH THE UPPER LOW CENTERED OVER THE UPPER MS RIVER VALLEY THIS AFTN. WILL CONTINUE DIVING DOWN THE PLAINS TONIGHT AND WILL REINFORCE THE COLD FRONT AND FORCE IT THROUGH OUR REGION.
543 PM MDT THU APR 21 2016 UPDATED GRIDS/FORECAST TO INCLUDE ISOLATED SHOWER AND THUNDERSTORM ACTIVITY OVER THE HIGH MOUNTAINS. UPPER RIDGE WILL SHIFT EAST TONIGHT WITH THE FLOW ALOFT BECOMING SOUTHWEST AND SOUTHERLY WINDS DEVELOPING ON THE PLAINS. WITH CAPES OF 300 J/KG OR LESS, WILL HOLD ON TO LOW POPS OVER THE HIGHER MOUNTAINS LATE IN THE AFTERNOON WITH NO CHANCE OF RAIN ON THE PLAINS. THE FLOW ALOFT WILL BECOME SOUTHWESTERLY FRIDAY NIGHT AS THE UPPER RIDGE AXIS SHIFTS TO THE EAST.
VFR CONDITIONS ARE EXPECTED THROUGH THE ENTIRE 06 UTC TAF CYCLE AS HIGH PRESSURE BUILDS ACROSS THE ROLLING PLAINS AND BIG COUNTRY.
ADVECTING MUCH COOLER AIR INTO OUR AREA. LOWS TONIGHT ARE EXPECTED TO RANGE FROM THE MID 30S ACROSS WEST CENTRAL WI TO THE LOWER 40S IN SOUTHERN MN. WINDS AND CLOUD COVER WILL DECREASE BY FRIDAY MORNING AS HIGH PRESSURE MOVES INTO OUR AREA.
LOW PRESSURE OVER SOUTHEAST IOWA WILL MOVE EAST ACROSS OUR REGION BRINGING NUMEROUS SHOWERS AND A FEW THUNDERSTORMS TONIGHT INTO FRIDAY. A RIDGE OF HIGH PRESSURE WILL MOVE EAST ACROSS INDIANA OVER THE WEEKEND.
THE LATEST RADAR DATA AND SURFACE OBS SHOW A COLD FRONT FROM NEAR COMSTOCK TO HONDO TO GONZALES. MUCH OF THE AREA HAS STABILIZED BEHIND THE COLD FRONT THIS EVENING.
A WEAK WAVE AHEAD OF THE COLD FRONT IS LEADING TO THIS PRE-FRONTAL BAND OF SHOWERS. THE COLD FRONT IS STILL BACK IN WESTERN TENNESSEE. CURRENT TRENDS AND HI-RES MODELS INDICATE THAT THERE WILL BE A BREAK IN THE PRECIPITATION LATE TONIGHT INTO EARLY FRIDAY MORNING BEFORE THE COLD FRONT ARRIVES. CHATTANOOGA AIRPORT, TN 59 74 54 77 / 70 70 10 0 KNOXVILLE MCGHEE TYSON AIRPORT, TN 57 73 55 76 / 100 70 20 10 OAK RIDGE, TN 58 73 53 75 / 100 70 20 10 TRI CITIES AIRPORT, TN 54 71 52 73 / 80 70 40 10.
THESE SHOWERS WERE OCCURRING IN AN AREA OF WEAK INSTABILITY AHEAD OF THE APPROACHING UPPER LOW. THE ACTIVITY WILL CONTINUE TO SPREAD ACROSS THE REGION AS THE LOW MOVES INLAND ON FRIDAY. INSTABILITY ALONG AND AHEAD OF A COLD FRONT WILL BE ACCOMPANIED BY A CHANCE OF THUNDERSTORMS FRIDAY AFTERNOON.
920 PM EDT THU APR 21 2016 HIGH PRESSURE IS RIDGING ACROSS THE AREA FROM THE ATLANTIC WITH A COLD FRONT MOVING THROUGH THE LOWER MS VALLEY REGION. THE FRONT WILL PUSH TOWARDS THE AREA AS THE RIDGE SHIFTS EAST THROUGH TOMORROW WITH SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS POSSIBLE FRIDAY. GENERALLY LIGHT E/SE FLOW WILL BE IN PLACE ACROSS THE AREA OVERNIGHT AS HIGH PRESSURE CONTINUES TO RIDGE ACROSS THE AREA.
627 PM CDT THU APR 21 2016 THE LOW PRESSURE SYSTEM WHICH BROUGHT THE MUCH NEEDED RAIN TO THE AREA OVER THE PAST FEW DAYS IS FINALLY MOVING OFF TO THE NORTHEAST.
WITH TEMPS SEVERAL DEGREES COOLER ONLY FURTHER INLAND. ESE WINDS ARE FORECAST TO VEER TO MORE SERLY TONIGHT AS HIGH PRESSURE OFF OF THE CAROLINAS DRIFTS FURTHER SE INTO THE WESTERN ATLC AND THE PRESSURE GRADIENT REMAINS FAIRLY TIGHT.
THE UPPER LEVEL TROUGH WHICH HELPED PRODUCE THE STORMS HAS MOVED EAST AS WELL.
759 PM EDT THU APR 21 2016 MOISTURE INCREASING AS COLD FRONT/UPPER LOW APPROACHES FOR A BRIEF UNSETTLED PERIOD. HIGH PRESSURE FOR THE WEEKEND.
744 PM EDT THU APR 21 2016 HIGH PRESSURE WILL MOVE EAST OF THE REGION TONIGHT WHILE LOW PRESSURE APPROACHES WESTERN NEW ENGLAND. THE LOW WILL CROSS THE REGION FRIDAY WITH A COLD FRONT.
AS THE SECOND WAVE OF PRECIP AIDED BY THE UPPER LOW OVER THE MIDWEST STATES DIVING SEWD BEGINS TO SPREAD INTO THE AREA. LATEST MODEL SUITES ARE SHOWING A BIT MORE BUOYANT ENERGY DEVELOPING OVER THE AREA IN ADVANCE OF THE WEAK COLD FRONT NEARING THE MS RIVER. THE COLD FRONT WILL CONTINUE TO MAKE ITS WAY EWD ACROSS THE CNTRL TN VALLEY FRI MORNING. SLIGHTLY COOLER AIR OUT OF THE N WILL ALSO FILTER INTO THE AREA HEADING INTO THE START OF THE WEEKEND PERIOD. AS A LARGE DOME OF HIGH PRESSURE BUILDS INTO THE REGION.
THOSE STORMS WERE SUPPORTED FROM ABOVE BY A SHORT WAVE ROTATING AROUND AN UPPER LOW OFFSHORE. ADDITIONAL SHORT WAVES ROTATING AROUND THIS LOW WILL BRING ROUNDS OF SHOWER AND THUNDERSTORM ACTIVITY TO THE AREA INTO FRIDAY. THE LOW ITSELF WILL SUPPORT MORE CONVECTION AS IT MOVES OVER THE CWA FRIDAY AFTERNOON INTO FRIDAY EVENING. IT WILL BE COOLER FRIDAY WITH HIGHS NEAR NORMAL ALONG THE COAST AND 5 TO 10 DEGREES BELOW NORMAL OVER THE REMAINDER OF THE AREA.
/ISSUED 240 PM CDT THU APR 21 2016/ A RIDGE OF HIGH PRESSURE OFF TO OUR WEST WILL PROVIDE A BRIEF CHANGE IN WEATHER FROM WHAT WE HAVE SEEN THE PAST FEW DAYS. THE REASONING BEHIND THIS DECISION IS THE AFOREMENTIONED RIDGE OF HIGH PRESSURE AND ASSOCIATED WEAK STEERING FLOW.
HIGH PRESSURE CENTERED JUST OFF THE CAROLINAS COAST WILL CONTINUE TO DRIFT TO THE SOUTHEAST TONIGHT INTO FRIDAY. THERE SEEMS TO BE FAIRLY GOOD AGREEMENT AMONGST THE VARIOUS SOURCES OF GUIDANCE AND ALSO CONSISTENT GUIDANCE OVER THE LAST FEW DAYS INDICATING DEEP MOISTURE ENTERING SOUTH FLORIDA ON FRIDAY IN ADVANCE OF A COLD FRONT ENTERING THE SOUTHEAST STATES AND THE NORTHERN GULF. THE GUIDANCE HAS ALSO BEEN VERY CONSISTENT INDICATING THAT A MID TO UPPER LEVEL TROUGH WILL BUILD INTO THE CENTRAL TO EASTERN GULF WITH COOLING MID-LEVEL TEMPERATURES. ALTHOUGH THE LATEST TREND IS A BIT COOLER THAN PREVIOUS GUIDANCE AT A COUPLE OF DEGREES COOLER THAN CLIMATOLOGY VALUES.
AND FAVORED LOCATION ALONG THE EDGE OF DEPARTING CLOUD DECK UNDER THE UPPER TROUGH WAS RESULTING IN FOG REPORTED AT KGBG AND KVYS AT 11 PM. UPPER LOW OVER SOUTH CENTRAL IOWA SPINNING TO THE EAST SOUTHEAST AT 20 MPH WITH AREAS OF SHOWERS WITH SCATTERED THUNDERSTORMS ALONG MISSISSIPPI RIVER. THIS SHOULD RESULT IN HIGHS MOSTLY IN THE LOWER TO MIDDLE 60S WITH ISOLATED UPPER 60S SOUTHWEST SECTIONS.
THE GFS DETERMINISTIC PREDICTS INCREASING SUBSIDENCE/UPPER CONVERGENCE OVER THE CWA/MSA TONIGHT/FRIDAY AS AN UPPER RIDGE AXIS MOVES ACRS THE CNTRL CONUS.
Low temperatures will be predominantly in the low to mid 50s tonight. The low will drop southeastward through northeast MO and central IL with the cold front also dropping southeastward through our forecast area late this afternoon and this evening. With steep lapse rates and low freezing level height a few storms may produce hail, mainly across west central or southwest IL, northeast and east of STL. GKS Upper level low will be to our east on Friday, but will still see some diurnal cu develop over portions of forecast area, mainly along and east of Mississippi River as secondary frontal boundary slides southeast through region.
The low will drop southeastward through northeast MO and central IL with the cold front also dropping southeastward through our forecast area late this afternoon and this evening. With steep lapse rates and low freezing level height a few storms may produce hail, mainly across west central or southwest IL, northeast and east of STL. GKS Upper level low will be to our east on Friday, but will still see some diurnal cu develop over portions of forecast area, mainly along and east of Mississippi River as secondary frontal boundary slides southeast through region.
1053 PM EDT THU APR 21 2016 HIGH PRESSURE WILL MOVE EAST OF THE REGION OVERNIGHT WHILE LOW PRESSURE APPROACHES WESTERN NEW ENGLAND. THE LOW WILL CROSS THE REGION FRIDAY WITH A COLD FRONT.
Overnight lows will be in the low 40s northwest to mid 40s southeast. For Friday, weak lee high plains troughing will resume with a downstream southerly wind for the forecast area evolving. Highs tomorrow will be a little warmer with 850-hPa warm air advection.
SOME MVFR CEILINGS WILL DEVELOP AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH DURING THE OVERNIGHT AND EARLY FRIDAY MORNING.
A cooler air mass was spreading across the area, which will lead to a chilly night. We will also keep the forecast dry as an upper level low pressure system finally exits to the east. An upper level ridge of high pressure translates across the nation's midsection, bringing sunny skies and temperatures near 80 to the Ozarks.