WTIN20 DEMS 260900 SPECIAL TROPICAL WEATHER OUTLOOK DEMS-RSMC TROPICAL CYCLONES NEW DELHI DATED 26.07.2026 SPECIAL TROPICAL WEATHER OUTLOOK FOR THE NORTH INDIAN OCEAN (THE BAY OF BENGAL AND THE ARABIAN SEA) VALID FOR THE NEXT 168 HOURS ISSUED AT 0600 UTC OF 26.07.2026 BASED ON 0300 UTC OF 26.07.2026. BAY OF BENGAL: DEPRESSION OVER NORTHWEST BAY OF BENGAL AND ADJOINING AREAS OF NORTH ODISHA- WEST BENGAL COASTS YESTERDAY\U2019S LOW PRESSURE AREA OVER WEST BENGAL COAST & ADJOINING NORTHWEST BAY OF BENGAL LAY AS A WELL-MARKED PRESSURE AREA OVER NORTHWEST BAY OF BENGAL & ADJOINING ODISHA-WEST BENGAL COASTS AT 0000 UTC OF TODAY, CONCENTRATED INTO A DEPRESSION AND LAY CENTRED AT 0300 UTC OF TODAY, THE 26TH JULY 2026, OVER THE SAME REGION NEAR LATITUDE 20.6ON AND LONGITUDE 88.4OE, ABOUT 130 KM SOUTH-SOUTHEAST OF SAGAR ISLAND (42903), 140 KM SOUTHEAST OF DIGHA (42901), 170 KM EAST OF CHANDBALI (42973) AND 180 KM EAST-SOUTHEAST OF BALASORE (42895). IT IS VERY LIKELY TO MOVE NORTHWESTWARDS, INTENSIFY FURTHER INTO A DEEP DEPRESSION DURING NEXT 24 HRS AND CROSS NORTH ODISHA AND WEST BENGAL COASTS BETWEEN PARADIP (42976) AND SAGAR ISLAND (42903) DURING 0600-0900 UTC OF 27TH JULY 2026. THE ESTIMATED CENTRAL PRESSURE IS 998 HPA. THE ASSOCIATED MAXIMUM SUSTAINED WIND SPEED IS 25 KT GUSTING TO 35 KT. SAGAR ISLAND REPORTED MEAN SEA LEVEL PRESSURE (MSLP) AS 998.7 HPA, PRESSURE CHANGE IN PAST 24 HRS (P24) AS -3.5 HPA, DEPARTURE FROM NORMAL (DEP) AS -1.2 HPA AND MAXIMUM SUSTAINED WIND SPEED (MSW) AS 400 / 02 KT. DIGHA (42901) REPORTED MSLP AS 998.9 HPA, DEP AS -1.0 HPA, P24 AS -1.8 HPA AND MSW AS 20 0 / 03 KT. BALASORE (42895) REPORTED MSLP AS 999.5 HPA, DEP AS -1.1 HPA, P24 AS -1.8 HPA AND MSW AS 360 0 / 02 KT. AS PER INSAT 3DS IMAGERY AT 0300 UTC OF 26TH JULY, THE INTENSITY OF THE SYSTEM IS CHARACTERISED AS T1.5. ASSOCIATED SCATTERED TO BROKEN LOW AND MEDIUM CLOUDS WITH EMBEDDED INTENSE TO VERY INTENSE CONVECTION LAY OVER NORTH AND CENTRAL BAY OF BENGAL (MINIMUM CLOUD TOP TEMPERATURE 73-90 DEG. CELSIUS). ARABIAN SEA: SCATTERED LOW AND MEDIUM CLOUDS WITH EMBEDDED WEAK TO MODERATE CONVECTION LAY OVER THE NORTH AND CENTRAL ARABIAN SEA. *PROBABILITY OF CYCLOGENESIS (FORMATION OF DEPRESSION) DURING NEXT 168 HRS: 24 24-48 48-72 72-96 96-120 120-144 144-168 HOURS HOURS HOURS HOURS HOURS HOURS HOURS NIL NIL NIL NIL NIL NIL NIL *NOTE: EVERY 24HR FORECAST IS VALID UPTO 0300 UTC (0830 IST) OF NEXT DAY REMARKS: SEA SURFACE TEMPERATURE (SST) IS 29-300C OVER NORTHWEST BAY OF BENGAL (BOB) AND ALONG & OFF NORTH ODISHA-WEST BENGAL-BANGLADESH COASTS AND AROUND 280C OVER MOST PARTS OF BOB. THE LOW LEVEL VORTICITY IS ABOUT 150 X 10-6 S -1 OVER NORTHWEST BAY OF BENGAL AND IS EXTENDING UPTO 500 HPA LEVEL. THE LOW LEVEL CONVERGENCE IS AROUND 20X10-6 S -1 OVER NORTHWEST & ADJOINING WESTCENTRAL BOB TO THE SOUTHWEST OF SYSTEM CENTRE. UPPER LEVEL DIVERGENCE IS AROUND 30 X 10-6 S -1 OVER NORTHWEST & ADJOINING NORTHEAST & CENTRAL BOB TO THE SOUTHEAST OF SYSTEM CENTRE. VERTICAL WIND SHEAR (BOTH MID (500-850 HPA) AND DEEP (200-850 HPA)) OF HORIZONTAL WIND IS LOW TO MODERATE (10-15 KT) OVER THE SYSTEM AREA AND ALONG THE PREDICTED PATH. THE IR-WV DIFFERENCE IMAGERY IS INDICATING TEMPERATURES LESS THAN -4 0C TO THE SOUTH OF SYSTEM CENTRE. THE GUIDANCE FROM NCICS MODEL INDICATES THE PREVALENCE OF WESTERLY WIND ANOMALY (5-7 MPS) OVER CENTRAL BOB, ALONG WITH EQUATORIAL ROSSBY WAVE (ERW) & APPROACHING KELVIN WAVE (KW) AND EASTERLY WIND ANOMALY (3-5 MPS) OVER NORTH & ADJOINING AREAS OF CENTRAL BOB ON 26TH JULY. HOWEVER, ON 27TH JULY, THERE IS ENHANCEMENT OF WESTERLY WIND ANOMALY (7-9 MPS) OVER CENTRAL & SOUTH BOB WITH PREVALENCE OF ERW, LOW FREQUENCY BACKGROUND WAVE(9LW) AND KW AND EASTERLY WIND ANOMALY (7-9 MPS) OVER NORTH BOB, I.E. ALL THE WAVES WILL BE IN PHASE ON 27TH JULY. ALL THESE FAVOURABLE FEATURES VIZ. HIGH SST, GOOD EQUATORWARD OUTFLOW, PRESENCE OF EQUATORIAL WAVES (ERW, KW, LW), LOW TO MODERATE VERTICAL WIND SHEAR, POSITIVE LOW LEVEL VORTICITY & LOW LEVEL CONVERGENCE AND UPPER LEVEL DIVERGENCE CONTRIBUTED TO THE INTENSIFICATION OF LOW-PRESSURE AREA OVER WEST BENGAL COAST & ADJOINING NORTHWEST BOB TO CONCENTRATE INTO A WELL MARKED LOW PRESSURE AREA AT 0000 UTC AND FURTHER INTO A DEPRESSION AT 0300 UTC OF 26TH JULY. GUIDANCE FROM NUMERICAL MODELS: VARIOUS NUMERICAL WEATHER PREDICTION MODELS (ECMWF, GFS GROUP, NCUM, ECAI, GFSAI ETC.) ARE INDICATING THE DEPRESSION OVER NORTHWEST BOB AND ADJOINING NORTH ODISHA-WEST BENGAL COASTS TO MOVE SLOWLY NORTHWESTWARDS AND INTENSIFY FURTHER DURING NEXT 24 HOURS. MODELS ARE ALSO INDICATING CROSSING OVER NORTH ODISHA-WEST BENGAL COASTS TO THE NORTH OF BALASORE DURING 0300- 0900 UTC OF 27TH JULY, 2026. CONSIDERING ALL THE ABOVE, THE DEPRESSION OVER NORTHWEST BAY OF BENGAL AND ADJOINING AREAS OF NORTH ODISHA -WEST BENGAL COASTS IS VERY LIKELY TO MOVE NORTHWESTWARDS AND CROSS NORTH ODISHA- WEST BENGAL COASTS DURING 0600-0900 UTC OF 27TH JULY, 2026. BASED ON THE OBSERVATIONS AND GUIDANCE FROM VARIOUS NUMERICAL MODELS: CONFIDENCE LEVEL IN ESTIMATION OF CURRENT LOCATION AND INTENSITY: HIGH CONFIDENCE LEVEL IN PREDICTION OF FORECAST TRACK: MODERATE CONFIDENCE LEVEL IN PREDICTION OF FORECAST INTENSITY: HIGH=