Monsoon Update 01 July 2026 — Low Pressure Area Likely Today over Northwest Bay, Depression Track Refined to Odisha–Chhattisgarh, Very Heavy Rain Gujarat Coast and Konkan 05 July, Delhi Onset 05–09 July

The Low Pressure Area (LPA) flagged in the 28 June analysis is active today over the Northwest Bay of Bengal — right on cue. The VayuMet model 01 July 00Z run confirms the system and refines the Depression track slightly southward compared to the previous run: the core heavy rainfall 04–06 July now targets Odisha and Chhattisgarh rather than central Madhya Pradesh. A new detail emerges — the Gujarat coast (Gulf of Khambhat zone) and Konkan receive very heavy rain on 05 July as the Depression draws deep moisture across the peninsula. Rajasthan shows an early rainfall signal on 03 July, the monsoon trough already extending northwest ahead of the system. The Tropical Easterly Jet (TEJ) continues at its strongest anomaly of the season.

India Meteorological Department Monsoon Status — 30 June 2026

The India Meteorological Department bulletin of 30 June 2026 confirms the Southwest Monsoon has advanced into some more parts of Madhya Pradesh, remaining parts of Chhattisgarh, Jharkhand and Bihar, some parts of Uttar Pradesh, most parts of Uttarakhand, and some parts of Himachal Pradesh and Ladakh. The 2026 monsoon has been broadly on schedule and has now covered most of peninsular and Central India. Remaining areas outside the onset line include most of Rajasthan, parts of western Uttar Pradesh, Punjab, Haryana, Jammu and Kashmir, and the far northwestern plains.

VayuMet Model Analysis — 01 July 2026

Model IC: 01 July 2026 00 UTC. Period one: 01–05 July · Period two: 06–10 July. Anomalies vs 1991–2020 Long Term Mean (MSLP vs 1981–2010 NCEP R2).

Fig. 1 — Mean Sea Level Pressure (top) · MSLP Anomaly vs Long Term Mean (bottom) · 01–05 July left · 06–10 July right · VayuMet Model · IC: 01 Jul 2026 00 UTC

MSLP — Low Pressure Area on the Odisha Coast Today; Depression Inland over Odisha–Chhattisgarh 04–06 July

The 01–05 July MSLP field (top-left) clearly shows a closed low over the Northwest Bay of Bengal and Odisha coast — the Low Pressure Area is active now. The negative anomaly (bottom-left) is centred over the Bay and extends inland over Odisha and Jharkhand, with values of −6 to −10 hPa. By 06–10 July (bottom-right) the anomaly has deepened and shifted slightly inland over Odisha and Chhattisgarh — the Depression track in this run sits about two degrees south of the 28 June forecast, with the monsoon trough extending strongly northwest into Rajasthan. The positive anomaly over northwest India (Arabian Sea ridge) has collapsed, confirming the trough is locking in across the country.

Fig. 2 — Cumulated Rainfall (top) · Rain Anomaly vs 1991–2020 Long Term Mean (bottom) · 01–05 July left · 06–10 July right · VayuMet Model · IC: 01 Jul 2026 00 UTC

Precipitation — Gujarat Coast and Konkan Active 01–05 July; Odisha, Chhattisgarh and Central India Major Episode 06–10 July

The 01–05 July rainfall (top-left) is already heavy along the West Coast, Konkan and Northeast India, with a positive anomaly over the Gujarat coast and Konkan as the Low Pressure Area's westward moisture pull activates. The 06–10 July panel (top-right) shows a dramatic intensification — a very large positive anomaly blankets Odisha, Chhattisgarh, Vidarbha, Madhya Pradesh, the Gangetic plains and the Gujarat coast. The West Coast remains highly active throughout. This is the most spatially extensive positive rain anomaly of the season so far, reflecting the combined influence of the Depression, an energised monsoon trough and a surging Arabian Sea low-level jet.

Fig. 3 — Mean 2 m Temperature (top) · Temperature Anomaly vs July Long Term Mean (bottom) · 01–05 July left · 06–10 July right · VayuMet Model · IC: 01 Jul 2026 00 UTC

Temperature — Heat Persists Northwest India 01–05 July; Rapid Cooling Odisha, Central India and Gangetic Plains 06–10 July

Rajasthan, Punjab and Haryana show a strong positive anomaly of +8 to +12°C in the 01–05 July period — the pre-monsoon heat pocket now compressed into the far northwest. Central India is near-normal, consistent with an active but not yet dominant monsoon. By 06–10 July, the Depression's cloud cover and heavy rain drive a sharp broad cooling across Odisha, Chhattisgarh, Madhya Pradesh and the Uttar Pradesh plains, with below-normal temperatures spreading rapidly. The northwest heat zone contracts to its smallest extent of the season, though far west Rajasthan retains some warmth — consistent with monsoon onset still pending for that corner.

Fig. 4 — Mean Wind at 850 hPa (top) · Wind Anomaly vs Long Term Mean (bottom) · 01–05 July left · 06–10 July right · VayuMet Model · IC: 01 Jul 2026 00 UTC

850 hPa Wind — Cyclonic Circulation Northwest Bay Today; Inland Track Odisha–Chhattisgarh 06–10 July; Arabian Sea Low-Level Jet Surging into Rajasthan

The 01–05 July anomaly (bottom-left) reveals a well-defined cyclonic positive anomaly over the Northwest Bay of Bengal — the Low Pressure Area's inflow signature — with enhanced south-westerlies pushing into Gujarat and Rajasthan, breaching above Long Term Mean for the first time this season. By 06–10 July (bottom-right) the cyclonic anomaly has shifted to Odisha and Chhattisgarh, while the Arabian Sea low-level jet strengthens further into Rajasthan. Easterlies from Bihar and eastern Uttar Pradesh feed the system from the northeast — the classic two-limb Monsoon Depression circulation. This pattern confirms the monsoon trough has extended northwest of its climatological mean position.

Fig. 5 — Mean Wind at 200 hPa (top) · Wind Anomaly vs Long Term Mean (bottom) · 01–05 July left · 06–10 July right · VayuMet Model · IC: 01 Jul 2026 00 UTC

200 hPa Wind — Tropical Easterly Jet at Seasonal Peak; Upper Anticyclone Firmly Established over India

The Tropical Easterly Jet, the upper-tropospheric easterly current that sustains deep monsoon convection through upper-level divergence, is at its strongest positive anomaly of the season in the 01–05 July period — a broad enhanced easterly signal spanning south India, the Bay of Bengal and the tropical Indian Ocean. The upper anticyclone over the Indian subcontinent is firmly established. In the 06–10 July period the signal is strong over Central and North India — directly above the Depression track — confirming that the upper-level outflow needed to sustain a vigorous Depression is in place. The subtropical westerly jet has retreated completely poleward, removing all upper-level inhibition.

District-level Heavy Rain Alerts — 03–06 July

VayuMet district-level forecasts flag the following districts for 24-hour very heavy or extremely heavy rainfall. These are model-based guidance values; always refer to the latest India Meteorological Department district warnings for official advisories.

Date	State	Districts / Region	Alert
03 July	Rajasthan	Jhalawar	VERY HEAVY
05 July	Gujarat	Narmada, Surat, Bharuch, Valsad, Navsari	VERY HEAVY
	Maharashtra	Palghar	VERY HEAVY
	Odisha	Baudh, Kandhamal	VERY HEAVY
06 July	Odisha	Kalahandi, Sonepur, Bargarh, Nuapada, Nabarangapur, Rayagada	VERY HEAVY
	Chhattisgarh	Mahasamund, Gariaband	VERY HEAVY

VayuMet Outlook — 01 to 10 July 2026

01–05 July: Active monsoon continues over the West Coast, Konkan, Northeast India and coastal Odisha today. The Low Pressure Area over the Northwest Bay will deepen over the next 48–72 hours. Gujarat coast and Konkan see very heavy rain by 05 July driven by the system's westward moisture surge. Rajasthan receives organised rainfall from 03 July as the monsoon trough extends northwest — Jhalawar the first district flagged. Heat persists over far northwest India (Punjab, Haryana, far west Rajasthan) but is now clearly in retreat. Monsoon is expected to advance into remaining parts of Gujarat, western Uttar Pradesh and western Rajasthan during this window.

06–10 July — Active Depression Phase: The Low Pressure Area is expected to concentrate into the season's first Monsoon Depression around 04–05 July and track west-northwestward, with its core rainfall now centred over Odisha and Chhattisgarh — a track slightly south of the 28 June forecast. The heavy rain footprint remains vast: Odisha, Chhattisgarh and Vidarbha under the Depression's direct circulation; the Gangetic plains (Bihar, eastern Uttar Pradesh) drawing easterlies; the West Coast and Gujarat sustained by the Arabian Sea low-level jet surge; and Uttarakhand receiving heavy orographic rainfall along the Himalayan foothills. The Tropical Easterly Jet at upper levels is at its most intense, confirming the full-depth dynamical vigour of this active phase. Monsoon onset over most of Rajasthan is likely by 05–07 July, with only far northwest India remaining outside the Monsoon Northern Limit.

Delhi Monsoon Onset — VayuMet Model Signals 05–10 July

Delhi's monsoon onset is one of the most watched events in the Indian meteorological calendar. The climatological normal date is 27 June — the 2026 season is already running 5 days behind as of today. VayuMet district-level model data for Delhi and the National Capital Region (including Gurugram, Faridabad, Ghaziabad and Gautam Buddha Nagar) provides a day-by-day picture:

Date	Avg Rain NCR	Max Rain NCR	Max Temp Delhi	Signal
01–04 July	< 6 mm	< 12 mm	37–41 °C	Pre-monsoon heat, trough distant
05 July	9.6 mm	16 mm	40 °C	Rain & wind onset conditions met — temperature above threshold
06 July	0.7 mm	3 mm	32 °C	Temperature crashes — Depression cloud shield; rain negligible
07–08 July	1–2 mm	2–3 mm	37–38 °C	Trough positioning, partial recovery
09 July	14.6 mm	26 mm	34 °C	Sustained organised rainfall — onset window
10 July	5.7 mm	8 mm	37 °C	Continued monsoon activity

05 July is a significant marker: with average NCR rainfall of 9.6 mm and maximum of 16 mm alongside south-westerly wind conditions, the rain and wind criteria for Delhi monsoon onset are broadly met on this date. The single factor holding back declaration is the maximum temperature remaining at 40°C — well above the threshold for sustained monsoon conditions. IMD's onset criteria require concurrent rainfall, wind and temperature suppression. On 06 July the temperature crashes sharply to 32°C as the Depression's cloud canopy passes to the south — but rainfall on this date is negligible, so onset criteria flip: temperature is met but rain is not. The first date where both rainfall and temperature signals align is 09 July, with 14.6 mm average across the National Capital Region and maximum temperature down to 34°C — the most probable onset date under the current Depression track.

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