Cherry Blossom Festival
The annual Cherry Blossom Festival is underway in Washington D.C. (March 20th – April 14th). However, the webcam below from the National Park Service didn’t show any blooms. Thanks to cooler weather this spring, the bloom dates are predicted to be a little later than the average bloom date of April 4th.
2015 Peak Bloom Predication Dates: April 11 – 14, 2015
Average Peak Bloom Date: April 4
Exactly when the buds will open is not easy to predict and it is extremely difficult to give an accurate forecast much more than 10 days before peak bloom. National Park Service horticulturists monitor five distinct stages of bud development and provide timely forecasts and updates.
The Peak Bloom Date is defined as the day on which 70 percent of the blossoms of the Yoshino cherry trees that surround the Tidal Basin are open. This date varies from year to year, depending on weather conditions. The Blooming Period is defined as that period when 20 percent of the blossoms are open until the petals fall and leaves appear. The blooming period starts several days before the peak bloom date and can last as long as 14 days, however, frost or high temperatures combined with wind or rain can shorten this period.
See more from the NationalCherryBlossomFestival.org HERE:
National Weather Outlook
A look at the weather loop below and you’ll notice a lack of any major storm systems moving through the middle part of the country through Tuesday. It appears that March will go out like a lamb this year, but a developing storm system will bring severe thunderstorm and heavy rain chances back into the conversation by the end of the week.
Severe Weather Threats Ahead
The Storm Prediction Center has issued a thunderstorm risk for each day this week!
Monday
…EXTREME SRN AL/FL PANHANDLE/SW GA TODAY…
A SHORTWAVE TROUGH OVER THE TN VALLEY WILL PROGRESS ESEWD TO THE SE
ATLANTIC COAST BY ABOUT 21Z…AS A WEAKENING COLD FRONT DRIFTS SWD
ACROSS GA/AL/MS. ONGOING STORMS IN A BAND THIS MORNING FROM E
CENTRAL MS INTO CENTRAL AL AND N GA ARE EXPECTED TO WEAKEN BY MID
MORNING. JUST S OF THE ONGOING STORMS AND ASSOCIATED
OUTFLOW…BOUNDARY LAYER DEWPOINTS WILL INCREASE TO NEAR 60 F IN
CONJUNCTION WITH DAYTIME HEATING…SUCH THAT MLCAPE COULD APPROACH
1000 J/KG BY EARLY AFTERNOON.
THE PRIMARY CONCERN FOR THIS AREA WILL BE SOURCES FOR ASCENT TO
SUPPORT ADDITIONAL THUNDERSTORM DEVELOPMENT FROM 18-21Z. THE
SHORTWAVE TROUGH WILL MOVE E OF NE EDGE OF THE MOIST SECTOR NEAR OR
JUST AFTER 18Z…LEAVING THE REMNANT OUTFLOW/FRONT AS THE ONLY
IDENTIFIABLE FOCUS FOR CONVECTIVE INITIATION. ALSO…LOW-LEVEL FLOW
AND SHEAR WILL WEAKEN SUBSTANTIALLY AFTER MIDLEVEL WAVE
PASSAGE…LEAVING AN ENVIRONMENT WITH POTENTIAL MODERATE BUOYANCY
AND DEEP-LAYER SHEAR…BUT LITTLE HODOGRAPH STRUCTURE IN THE LOW
LEVELS. WILL RETAIN LOW HAIL/WIND PROBABILITIES IN CASE ADDITIONAL
STORMS FORM NEAR OR JUST AFTER MIDDAY ALONG THE RESIDUAL SURFACE
BOUNDARY…BUT COVERAGE SHOULD REMAIN ISOLATED.
Tuesday
…S-CNTRL/SOUTHEAST STATES…
30/00Z KDRT/KFWD/KSHV RAOBS SAMPLED MEAN MIXING RATIOS AROUND 8-9
G/KG NEAR THE LEAD FRONT WITH 10-11 G/KG RATIOS ALONG THE WRN/CNTRL
GULF COAST. BOUNDARY-LAYER MOISTURE WILL CONTINUE TO GRADUALLY
MODIFY WITHIN THE WARM SECTOR BENEATH AN INITIALLY PERVASIVE EML
PLUME. BUT GUIDANCE APPEARS LARGELY OVERDONE WITH DEPICTING 12-13
G/KG MEAN MIXING RATIOS ALONG THIS LEAD FRONT ON TUE AFTERNOON.
NEVERTHELESS…STRONG DIABATIC SURFACE HEATING AMIDST RELATIVELY
COLD MID-LEVEL TEMPERATURES SHOULD YIELD A BROAD WEAK TO MODERATELY
UNSTABLE AIR MASS WITH DIMINISHING MLCIN RELATIVE TO PRIOR DAYS.
SPATIAL DETAILS OF WHEN/WHERE CONVECTION WILL FORM APPEAR UNCLEAR
GIVEN SUBTLE FORCING FOR ASCENT. BUT CONVERGENCE ALONG THE DRYLINE
AND THE PAIR OF WEAK FRONTAL BOUNDARIES SHOULD RESULT IN SCATTERED
TSTMS DEVELOPING IN THE AFTERNOON/EVENING.
DEEP-LAYER SHEAR WILL BE STRONG OVER THE MID-SOUTH/TN VALLEY UNDER
THE PERIPHERAL INFLUENCE OF THE NORTHEAST TROUGH. PRIMARY
UNCERTAINTY HERE IS JUST HOW MOIST THE AIR MASS WILL BE ON THE
FRINGE OF GREATER INSTABILITY. FARTHER WEST ALONG THE RED RIVER
AREA…INSTABILITY WILL BE LARGER BUT MID-LEVEL FLOW WILL WEAKEN
WITH WRN EXTENT AS THE HEIGHT GRADIENT RELAXES BETWEEN THE NRN GREAT
PLAINS RIDGE AND RIO GRANDE VALLEY TROUGH. CONFIDENCE IS TOO LOW IN
FAVORABLE OVERLAP OF THERMODYNAMIC/KINEMATIC PARAMETERS TO WARRANT
MESOSCALE UPGRADES TO SLIGHT RISK THIS OUTLOOK.
Wednesday
…UPPER MIDWEST TO CNTRL GREAT PLAINS…
POLEWARD TRANSPORT OF A MODIFIED SRN GREAT PLAINS AIR MASS WILL
STRENGTHEN LATE D2 IN ADVANCE OF THE SHORTWAVE TROUGH REACHING THE
CANADIAN PRAIRIES. ROBUST BOUNDARY LAYER MIXING WITH STRONG DIABATIC
HEATING OVER THE WARM SECTOR SHOULD RESULT IN A PLUME OF 50S SURFACE
DEW POINTS REACHING INTO PARTS OF SRN MN AND THE MID-MO TO MID-MS
VALLEYS BENEATH A PERVASIVE EML. MODERATE SPATIAL DIFFERENCES EXIST
IN GUIDANCE WITH BOTH THE PLACEMENT OF THE COLD FRONT AND DRYLINE ON
WED AFTERNOON…WHICH WILL BE CRUCIAL FOR LOCATION OF SURFACE-BASED
TSTM INITIATION. CONVERGENCE ALONG THESE BOUNDARIES IN CONJUNCTION
WITH DECREASING INHIBITION SHOULD FOSTER SCATTERED TSTM DEVELOPMENT.
RATHER STEEP MID-LEVEL LAPSE RATES AND 30-40 KT EFFECTIVE SHEAR WILL
FOSTER LARGE HAIL AS THE PRIMARY INITIAL RISK. BUT AS MID-LEVEL
HEIGHT FALLS INCREASE AND 700-500 MB SWLYS STRENGTHEN DURING THE
EVENING…THIS SHOULD YIELD A PREDOMINANT LINEAR MODE TO CONVECTION.
LEWP/BOWING SEGMENTS WITH A MIX OF SEVERE WIND/HAIL ARE POSSIBLE. AN
MCS MAY LINGER SEWD WED NIGHT TOWARDS THE LOWER MO VALLEY AS A
STRONG LLJ OFFSETS INCREASING MLCIN.
Thunderstorm Outlook Late Week
…DISCUSSION…
ORGANIZED SEVERE STORMS ARE POSSIBLE FROM PARTS OF THE RED RIVER TO
MID-MS VALLEYS ON D4 AND FARTHER S OVER THE LOWER MS VALLEY ON D5.
PREVAILING SWLYS AT 700 MB WITH A PERVASIVE EML SUGGEST
DIURNALLY-DRIVEN D4 CONVECTION WILL LIKELY REMAIN FORCED BY
CONVERGENCE ALONG A SEWD-SAGGING COLD FRONT FROM THE MID-MO VALLEY
TO ITS INTERSECTION WITH THE DRYLINE OVER OK. GUIDANCE HAS LARGELY
TRENDED SLOWER WITH THE EWD EVOLUTION OF A SHORTWAVE TROUGH EXPECTED
TO BE CENTERED NEAR THE GREAT BASIN AT 12Z/THU. SUBSTANTIAL
STRENGTHENING OF MID-LEVEL WLYS OVER THE S-CNTRL CONUS WARM SECTOR
APPEARS DELAYED UNTIL LATE D4 INTO D5. NEVERTHELESS…A CONTINUED
GRADUAL INCREASE IN WARM SECTOR BOUNDARY LAYER DEW POINTS IS
ANTICIPATED THROUGH THIS TIME FRAME…YIELDING POTENTIALLY THE
LARGEST INSTABILITY THIS WEEK NEAR THE TRIPLE-POINT OF THE
DRYLINE/COLD FRONT INTERSECTION IN OK. WITH A RAPID EVENING INCREASE
IN THE LLJ PROGGED AHEAD OF THE WRN TROUGH…SEVERE STORMS COULD
DEVELOP LATE DAY AND BE SUSTAINED INTO THU NIGHT.
CONSENSUS OF GUIDANCE SUGGESTS THAT WEAK CYCLOGENESIS WILL OCCUR
ALONG THE FRONTAL ZONE AS THE WRN TROUGH PROGRESSES INTO THE CNTRL
STATES ON D5. SPATIOTEMPORAL PREDICTABILITY OF THIS PROCESS AND
SUBSEQUENT ACCELERATION OF A COLD FRONT INTO LOWER MS VALLEY IS LOW.
HOWEVER…PROBABLE PRESENCE OF A RICH MOIST BOUNDARY LAYER WITH THE
LAST VESTIGES OF THE EML IN CONJUNCTION WITH AMPLIFYING TROPOSPHERIC
FLOW FIELDS SUGGEST THAT A FAVORABLE ENVIRONMENT FOR SEVERE STORMS
SHOULD EXIST AT SOME POINT ON D5.
BEYOND THESE TIME FRAMES…SEVERE POTENTIAL SHOULD BE LOW THROUGH
THE WEEKEND AS CONTINENTAL POLAR AIR REACHES THE NRN GULF COAST. BUT
THIS SHOULD BE SHORT-LIVED AS RETURN FLOW QUICKLY COMMENCES BENEATH
A BUILDING EML EARLY NEXT WEEK. THIS MAY YIELD AN INCREASE IN SEVERE
STORM ACTIVITY BEYOND THE D8 PERIOD.
Thursday
Friday
5 Day Precipitation Outlook
According to NOAA’s HPC, the 5 day precipitation outlook suggests some of the heaviest precipitation over parts of the Ohio/Tennessee Valley and the Northeast through late this week. 1″ to 2″+ may be possible with some of the showers and thunderstorms.
Thanks for checking in and have a great rest of your week! Don’t forget to follow me on Twitter @TNelsonWX
