Bay of Bengal: Deep Depression (94B)

[senorpepr]

Watching that area in the N Bay of Bengal, S of Bangladesh.

No invest number listed on NRL. Nothing on JTWC's Indian Ocean outlook (we'll see if that is updated at 18Z).

Here's what IMD is saying...

WTIN20 DEMS 190515

TROPICAL WEATHER OUTLOOK
------------------------
DEMS -RSMC TROPICAL CYCLONES NEW DELHI 19 JUL, 2009 (.) TROPICAL WEATHER OUTLOOK FOR NORTH INDIAN OCEAN (THE BAY OF BENGAL AND THE ARABIAN SEA ) VALID FOR NEXT 24 HOURS ISSUED AT 0600 UTC (.)

CONVECTIVE CLOUDS ARE SEEN OVER CENTRAL AND ADJOING PARTS OF NORTH BAY OF BENGAL (.) CONVECTIVE CLOUDS ARE ALSO SEEN OVER PARTS OF NORTHWEST AND SOUTHEAST ARABIAN SEA (.) RIDGE LINE AT 200 HPA PASSES ALONG LATITUDE 32.0 DEG. NORTH OVER INDIAN REGION (.)


SSD, however, has been fixing the disturbance. No floater yet, but they're giving it a T1.0 on Dvorak.


156
TXIO24 KNES 190917


A. TROPICAL DISTURBANCE

B. 19/0830Z

C. 20.1N

D. 89.3E

E. FIVE/MET-7

F. T1.0/1.0/D1.0/24HRS

G. IR/EIR/VIS

H. REMARKS...DT=1.0 BASED ON 1/10 BANDING. MET AND PAT ALSO
1.0. QUICKSCAT WINDS ALSO SHOW CIRCULATION DEVELOPING IN REGION.

I. ADDL POSITIONS

NIL


...SWANSON

[senorpepr]

WWIN40 DEMS 190300 CCA

I W B 19TH JULY 2009 MNG:
=======================
THE LOPAR OVER NW BAY OF BENGAL AND ADJ COASTAL AREAS OF NORTH
ORISSA AND WEST BENGAL NOW LIES AS A WELL MARKED LOW OVER THE
SAME AREA (.) ASSOCIATED CYCIR EXTDS UPTO MTLS TILTING SW WARDS
WITH HEIGHT SYSTEM IS LIKELY TO INTENSIFY INTO A DEPRESSION (.)
THE AXIS OF MONSOON TROUGH AT S.L. PASSES THROUGH FZP,PTL,MZN,
MTH , MZF ,DNB, CENTRE OF WELL MARKED LOW AND THENCE SE WARDS
TO E C BAY OF BENGAL (.) THE OFF-SHORE TROUGH AT S.L. FROM
SOUTH GUJRAT COAST TO KRL COAST PERSISTS (.) THE CYCIR EXTDG
UPTO 5.8 KM ASL OVER GUJRAT STATE AND N/H PERSISTS (.) THE CYCIR
EXTDG UPTO 3.6 KM ASL OVER NORTH PAK AND N/H NOW LIES OVER
J AND K AND N/H, SYATEM IS LIKELY TO MOVE ENE WARDS (.)
THE SW MONSOON HAS BEEN VIGROUS IN ORISSA AND ACTIVE IN NMMT AND
GUJRAT STATE, IT HAS BEEN SUBDUED OVER HARYANA MARATHWADA,
TLGNA RYSMA (.)
FORECAST .- RA/TSRS ARE LIKELY TO OCCAR AT MANY PLACES IN
A/ N IDS , AR PR, ASS & MEGHA, NMMT, WB/SKM , ORI, JHKD,BHR, S RAJ , GUJ STATE, KON / GOA, M.MAHA, VID,NORTH CHTGH, CAP, KKA,
KERALA AND LKDP ,AT A FEW PLACES UP,UTTARAKHAND,HRY,
PJB , HP, J AND K, N RAJ, WEST MP, MTWDA, TLGNA AND
AT ISOLATED PLACES OVER THE REST OF THE COUNTRY (.)
HRW,- XX TO VXX RAIN LIKELY TO OCCUR AT ISOLATED PLACES IN
A/N IDS, ORI, KON / GOA , COT KKA AND KERALA URING NEXT
48 HOURS (.)
HVY RAIN ALSO LIKELY TO OCCUR AT ISOLATED PLACES IN GWB
GUJRAT STATE M MAHARASHTRA , INT KKA DURING THE SAME PERIOD (.)

[senorpepr]

No change...


500
TXIO24 KNES 192050


A. TROPICAL DISTURBANCE

B. 19/2030Z

C. 20.4N

D. 88.3E

E. FIVE/MET-7

F. T1.0/1.0/D1.0/24HRS

G. IR/EIR/TMI

H. REMARKS...DT OF 1,5 BASED ON .3 BANDING. MET AND PT ARE 1.0.
FT BASED ON MET.

I. ADDL POSITIONS

19/1612Z 20.1N 88.5E TMI


...LIDDICK

[senorpepr]

440
TPIO10 PGTW 200619

A. TROPICAL DISTURBANCE 94B (BAY OF BENGAL)

B. 20/0530Z

C. 20.5N

D. 88.1E

E. FIVE/MET7

F. T1.0/1.0/INIT OBS

G. IR/EIR/VIS/MSI

H. REMARKS: 40A/PBO SBC/ANMTN. DT IS 1.0 BASED ON .20 WRAP ON LOG SPIRAL. PT ALSO 1.0.

I. ADDITIONAL POSITIONS: NONE


BRANDON

[senorpepr]

DEMS
RSMC TROPICAL CYCLONES NEW DELHI 20-07-2009

TROPICAL WEATHER OUTLOOK FOR NORTH INDIAN OCEAN (THE BAY OF BENGAL AND ARABIAN SEA) VALID FOR NEXT 24 HOURS ISSUED AT 0600 UTC OF 20 JULY, 2009 BASED ON 0300 UTC OF 20 JULY, 2009 (.)

LATEST SATELLITE IMAGERIES AND COASTAL OBSERVATIONS INDICATE THAT A DEPRESSION HAS FORMED OVER NORTHWEST BAY OF BENGAL AND LAY CENTRED AT 0300 UTC OF TODAY, THE 20 JULY 2009 NEAR LAT. 21.0 DEG. N AND LONG. 88.5 DEG. E, ABOUT 120 KM SOUTHEAST OF DIGHA (42901), 160 KM EAST-SOUTHEAST OF BALASORE (42895) AND 200 KM SOUTHWEST OF KHEPUPARA (41984).

SATELLITE IMAGERY INDICATES GRADUAL ORGANISATION OF CONVECTION DURING PAST TWELVE HOURS. THE INTENSITY OF THE SYSTEM IS T1.5. ASSOCIATED BROKEN INTENSE TO VERY INTENSE CONVECTION LIES OVER BAY OF BENGAL BETWEEN LAT. 18.5 DEG.N AND 21.5 DEG.N AND TO THE WEST OF LONG.
89.50E. THE LOWEST CLOUD TOP TEMPERATURE (CTT) DUE TO CONVECTION IS AROUND -70 DEG.C.

SUSTAINED MAXIMUM SURFACE WIND SPEED IS ESTIMATED TO BE ABOUT 25 KNOTS. THE STATE OF THE SEA IS ROUGH TO VERY ROUGH AROUND THE SYSTEM CENTRE. THE ESTIMATED CENTRAL PRESSURE IS ABOUT 992 HPA.

VERTICAL WIND SHEAR OF HORIZONTAL WIND OVER THE REGION IS LOW TO MODERATE (AROUND 10-20 KNOTS). SEA SURFACE TEMPRATURE IS ABOUT 29.0 DEG.C. THE SYSTEM IS SUPPORTED BY UPPER LEVEL DIVERGENCE AND LOWER LEVEL CONVERGENCE. STRONG EAST-SOUTHEASTERLY WINDS PREVAIL OVER THE REGION IN THE UPPER TROPOSPHERIC LEVEL. AS OBSERVED AT 0300 UTC OF TODAY, THE 24 HOURS PRESSURE FALL IS HIGHER IN THE WEST-NORTHWESTERLY DIRECTION AND IS MAXIMUM (-3.6 HPA) OVER DIGHA.

CONSIDERING ALL THE ABOVE, THE SYSTEM IS LIKELY TO INTENSIFY FURTHER AND MOVE IN A WEST-NORTHWESTERLY DIRECTION AND CROSS NORTH ORISSA WEST BENGAL COAST BETWEEN BALASORE AND DIGHA AROUND 1200 UTC OF TODAY, THE 20 JULY 2009.

[HURAKAN]

Exposed

[HURAKAN]

Development chances appear very low.

[ugaap]

Its now a Deep Depression.

Here is a Bulletin from RSMC New Delhi.

DEMS–RSMC TROPICAL CYCLONES NEW DELHI 20-07-2009

TROPICAL WEATHER OUTLOOK FOR NORTH INDIAN OCEAN (THE BAY OF BENGAL AND ARABIAN SEA) VALID FOR NEXT 24 HOURS ISSUED AT 1500 UTC OF 20 JULY, 2009 BASED ON 1200 UTC OF 20 JULY, 2009 (.)

THE DEPRESSION OVER NORTHWEST BAY OF BENGAL, MOVED WESTWARDS, INTENSIFIED INTO A DEEP DEPRESSION AND LAY CENTRED AT 1200 UTC OF TODAY, THE 20 JULY 2009 NEAR LAT. 21.00 N AND LONG. 88.00 E, ABOUT 100 KM SOUTHEAST OF DIGHA (42901), 120 KM EAST-SOUTHEAST OF BALASORE (42895) AND 250 KM WEST-SOUTHWEST OF KHEPUPARA (41984).

THE INTENSITY OF THE SYSTEM IS T2.0. ASSOCIATED BROKEN INTENSE TO VERY INTENSE CONVECTION LIES OVER NORTHWEST BAY OF BENGAL BETWEEN LAT. 18.50N AND 21.50N AND ORISSA AND CHHATTISGARH. THE LOWEST CLOUD TOP TEMPERATURE (CTT) DUE TO CONVECTION IS AROUND -700C.

SUSTAINED MAXIMUM SURFACE WIND SPEED IS ESTIMATED TO BE ABOUT 30 KNOTS. THE STATE OF THE SEA IS ROUGH TO VERY ROUGH AROUND THE SYSTEM CENTRE. THE ESTIMATED CENTRAL PRESSURE IS ABOUT 988 HPA.

VERTICAL WIND SHEAR OF HORIZONTAL WIND OVER THE REGION IS LOW TO MODERATE (AROUND 10-20 KNOTS). SEA SURFACE TEMPRATURE IS ABOUT 29.00 C. THE SYSTEM IS SUPPORTED BY UPPER LEVEL DIVERGENCE AND LOWER LEVEL CONVERGENCE. STRONG EAST-SOUTHEASTERLY WINDS PREVAIL OVER THE REGION IN THE UPPER TROPOSPHERIC LEVEL. HOWEVER THE SYSTEM IS MOVING CLOSER TO COAST. AS OBSERVED AT 1200 UTC OF TODAY, THE 24 HOURS PRESSURE FALL IS HIGHER IN THE WEST-NORTHWESTERLY DIRECTION.

CONSIDERING ALL THE ABOVE, THE SYSTEM IS LIKELY TO MOVE IN A WEST-NORTHWESTERLY DIRECTION AND CROSS NORTH ORISSA–WEST BENGAL COAST BETWEEN BALASORE AND DIGHA AROUND 1800 UTC OF TODAY, THE 20 JULY 2009.

[salmon123]

A. TROPICAL DISTURBANCE (94B)

B. 20/1430Z

C. 21.5N

D. 87.8E

E. THREE/MET-7

F. T1.5/1.5/D0.5/24HRS

G. IR/EIR

H. REMARKS... PRIMARY CONVECTION IS OVERLAND AND LLC WILL MAKE LANDFALL
SHORTLY. 2/10 BANDING FOR A DT OF 1.5. MET AND PT AGREE. FT BASED ON DT.

I. ADDL POSITIONS

NIL


...BIRCH

[Aslkahuna]

Unusual to see a disturbance in the BoB since the average for a July TC developing there is zero since the Monsoon Trough is usually overland in July in that area.

Steve

[Derek Ortt]

can we have some consistency from IMD?

This is the same intensity as a TC with an eye? PLEASE!

[theavocado]

Unusual to see a disturbance in the BoB since the average for a July TC developing there is zero since the Monsoon Trough is usually overland in July in that area.

Very, it's a rare case of the monsoon trough moving over water, a weakness in the STR bringing vertical wind shear down to moderate levels, and the Tropical Easterly Jet (TEJ) being a bit further south than normal. I don't expect it to last long, the convection already looks pretty sheared to me.

[theavocado]

JTWC took it off the NRL page, and looks like IMD put out their last bulletin. It was fun while it lasted.

TROPICAL WEATHER OUTLOOK FOR NORTH INDIAN OCEAN (THE BAY OF BENGAL AND ARABIAN SEA) VALID FOR NEXT 24 HOURS ISSUED AT 2100 UTC OF 20 JULY, 2009 BASED ON 1800 UTC OF 20 JULY, 2009 (.)

THE DEEP DEPRESSION OVER NORTHWEST BAY OF BENGAL, MOVED WEST-NORTHWESTWARDS, CROSSED NORTH ORISSA-WEST BENGAL COAST BETWEEN BALASORE (42895) AND DIGHA (42901) DURING 1600-1700 UTC OF YESTERDAY, THE 20 JULY 2009. IT LAY CENTRED AT 1800 UTC OF YESTERDAY, THE 20 JULY 2009 OVER NORTH ORISSA NEAR BALASORE.

THE INTENSITY OF THE SYSTEM IS T2.0. ASSOCIATED BROKEN INTENSE TO VERY INTENSE CONVECTION LIES OVER NORTHWEST BAY OF BENGAL BETWEEN LAT. 18.50N AND 21.50N AND ORISSA AND CHHATTISGARH. THE LOWEST CLOUD TOP TEMPERATURE (CTT) DUE TO CONVECTION IS AROUND -600C.

SUSTAINED MAXIMUM SURFACE WIND SPEED IS ESTIMATED TO BE ABOUT 30 KNOTS. THE STATE OF THE SEA IS ROUGH TO VERY ROUGH ALONG NORTH ORISSA AND ADJOINING WEST BENGAL COASTS. THE ESTIMATED CENTRAL PRESSURE IS ABOUT 992 HPA.

VERTICAL WIND SHEAR OF HORIZONTAL WIND OVER THE REGION IS BETWEEN 15-20 KNOTS. THE SYSTEM IS SUPPORTED BY UPPER LEVEL DIVERGENCE AND LOWER LEVEL CONVERGENCE. STRONG EAST-SOUTHEASTERLY WINDS PREVAIL OVER THE REGION IN THE UPPER TROPOSPHERIC LEVEL.

CONSIDERING ALL THE ABOVE, THE SYSTEM IS LIKELY TO MOVE IN A WEST-NORTHWESTERLY DIRECTION AND WEAKEN GRADUALLY.

THIS IS THE LAST BULLETIN FOR THIS SYSTEM.