{
  "schema_version": 1,
  "event": {
    "id": "satellite-flood:in-andhra-pradesh-cyclone-murasu-2026-11",
    "slug": "cyclone-murasu-andhra-pradesh-flooding-2026-11",
    "type": "satellite-flood",
    "type_label": "Flood (satellite analysis)",
    "source_id": "in-andhra-pradesh-cyclone-murasu-2026-11",
    "title": "Cyclone Murasu: satellite map of candidate flooded areas on the Andhra Pradesh coast",
    "seo_description": "Sentinel-1 radar and Sentinel-2 images show where new surface water appeared across Bapatla, Guntur and Prakasam after Cyclone Murasu made landfall near Ongole on 3 November 2026.",
    "description": "Bapatla, Guntur and Prakasam districts, Andhra Pradesh, India",
    "status": "satellite analysis",
    "severity": "Satellite analysis",
    "event_date": "2026-11-03",
    "country": "India",
    "province": "Andhra Pradesh",
    "district": "Bapatla, Guntur and Prakasam",
    "municipalities": [
      "Bapatla",
      "Ponnur",
      "Guntur",
      "Chirala",
      "Ongole"
    ],
    "event_summary": "Severe cyclonic storm Murasu crossed the Andhra Pradesh coast near Ongole in Prakasam district at about 1 am IST on Tuesday 3 November 2026, according to the India Meteorological Department (IMD). The UN and EU Global Disaster Alert and Coordination System (GDACS) gave the storm its highest, Red, alert. It arrived about a week after Cyclone Arnab, which had already hit the same coast. IMD warned of flash floods in Bapatla, Guntur, Krishna, Palnadu, Prakasam and SPSR Nellore districts. In the 24 hours to 8.30 am on 3 November, IMD recorded 22 cm of rain at Bapatla, and municipal gauges recorded about 313 mm at Ponnur and 298 mm in Guntur city. On 5 November officials told Chief Minister N. Chandrababu Naidu that eight people had died: five in Bapatla district, two in Guntur and one in Palnadu.",
    "reported_impacts": [
      {
        "label": "Deaths",
        "value": "8: five in Bapatla district, two in Guntur and one in Palnadu",
        "status": "official figures given to the Chief Minister's review",
        "source": "The News Minute",
        "url": "https://www.thenewsminute.com/andhra-pradesh/cyclone-murasu-8-dead-cm-naidu-estimates-damages-at-rs-1919-cr-in-andhra",
        "date": "5 November 2026"
      },
      {
        "label": "Crops",
        "value": "143,122 hectares of agricultural crops damaged, affecting 186,063 farmers; 6,749 hectares of horticultural crops",
        "status": "preliminary; officials said a fuller assessment would follow once floodwater receded",
        "source": "The News Minute",
        "url": "https://www.thenewsminute.com/andhra-pradesh/cyclone-murasu-8-dead-cm-naidu-estimates-damages-at-rs-1919-cr-in-andhra",
        "date": "5 November 2026"
      },
      {
        "label": "Homes, boats and roads",
        "value": "983 houses, 346 boats and 220 fishing nets damaged; 760 km of major district roads and state highways damaged",
        "status": "preliminary",
        "source": "The News Minute",
        "url": "https://www.thenewsminute.com/andhra-pradesh/cyclone-murasu-8-dead-cm-naidu-estimates-damages-at-rs-1919-cr-in-andhra",
        "date": "5 November 2026"
      },
      {
        "label": "Estimated losses",
        "value": "Rs 1,918.55 crore",
        "status": "preliminary",
        "source": "The News Minute",
        "url": "https://www.thenewsminute.com/andhra-pradesh/cyclone-murasu-8-dead-cm-naidu-estimates-damages-at-rs-1919-cr-in-andhra",
        "date": "5 November 2026"
      },
      {
        "label": "Heaviest rainfall",
        "value": "22 cm at Bapatla in the 24 hours to 8.30 am on 3 November (IMD); 312.76 mm at Ponnur and 298.36 mm in Guntur city (municipal gauges)",
        "status": "as reported",
        "source": "Deccan Chronicle; The Times of India",
        "url": "https://www.deccanchronicle.com/southern-states/andhra-pradesh/murasu-causes-crop-damage-flooding-in-south-coastal-ap-2001480",
        "date": "3 November 2026"
      }
    ],
    "source_updated_at": "2026-11-14",
    "checked_at": "2026-11-13T18:34:48Z",
    "imagery_before": "1, 6 and 26 Oct 2026",
    "imagery_after": "10 and 12 Nov 2026",
    "radar_after_dates": [
      "2026-11-09"
    ],
    "observations": [
      {
        "key": "descending-92",
        "sensor": "Sentinel-1 radar",
        "label": "Sentinel-1, 9 Nov (descending)",
        "date": "2026-11-09",
        "before_label": "16 Oct",
        "cross_geometry": false,
        "valid_pct": 100.0,
        "detected_ha": 15396.0
      },
      {
        "key": "sentinel-2",
        "sensor": "Sentinel-2 optical",
        "label": "Sentinel-2, 10 and 12 Nov",
        "date": "2026-11-12",
        "before_label": "1, 6 and 26 Oct 2026",
        "cross_geometry": false,
        "valid_pct": 93.7,
        "detected_ha": 25348.1
      }
    ],
    "candidate_count": 1739,
    "candidate_area_ha": 26398.9,
    "candidate_count_by_confidence": {
      "higher": 362,
      "moderate": 1377
    },
    "candidate_area_ha_by_confidence": {
      "higher": 15955.3,
      "moderate": 10443.6
    },
    "cropland_candidate_ha": 24125.3,
    "pre_event_water_ha": 19075.0,
    "road_length_near_candidates_m": 79751.0,
    "reference_comparison": null,
    "area_km2": 263.989,
    "bbox": [
      79.95,
      15.42,
      80.85,
      16.32
    ],
    "geometry": {
      "type": "Polygon",
      "coordinates": [
        [
          [
            79.95,
            15.42
          ],
          [
            80.85,
            15.42
          ],
          [
            80.85,
            16.32
          ],
          [
            79.95,
            16.32
          ],
          [
            79.95,
            15.42
          ]
        ]
      ]
    },
    "headline_figure": "1,739 candidate flooded areas covering 264 km²",
    "source_url": "https://www.gdacs.org/report.aspx?eventid=1001346&episodeid=10&eventtype=TC",
    "source_name": "TechnicalGIS analysis of Copernicus Sentinel-1 and Sentinel-2 data",
    "licence": "Derived map and data: CC BY 4.0 (TechnicalGIS); OSM-derived attributes: ODbL 1.0",
    "licence_url": "https://creativecommons.org/licenses/by/4.0/",
    "attribution": "Contains modified Copernicus Sentinel data [2026]. © OpenStreetMap contributors, available under the Open Database Licence (ODbL).",
    "area_method": "Candidate area is the planimetric area of the 20 m UTM zone 44N pixels in each polygon.",
    "analysis_note": "Satellite-detected surface water that was not there before the event. These are candidate flooded areas, not a confirmed flood extent, and they have not been checked on the ground.",
    "map_renderer": "flood-1"
  },
  "coverage": {
    "initial_area": "Bapatla, Guntur and Prakasam districts, Andhra Pradesh, India",
    "provider": "Copernicus Sentinel-1 and Sentinel-2 (via Microsoft Planetary Computer)",
    "scope_note": "The analysis covers a 0.90° × 0.90° box (79.95–80.85° E, 15.42–16.32° N) around Bapatla, Guntur and Prakasam districts, Andhra Pradesh, India. Water outside it, water that had drained before the satellites passed, and patches smaller than 2 ha are not included."
  },
  "captured_at": "2026-11-13T18:34:48Z",
  "method": {
    "summary": "Sentinel-1 radar backscatter (VV) after the event was compared with an image from before it: smooth open water returns very little radar energy, so ground that turned dark is treated as new surface water. Where a cloud-free Sentinel-2 image was available, a water index (MNDWI) was compared in the same way. Each observation counts separately; areas where two or more observations each detected water over at least a quarter of the area are higher confidence.",
    "thresholds": {
      "pixel_m": 20.0,
      "sar_window_px": 3,
      "sar_water_db_max": -18.0,
      "sar_drop_db_min": 3.0,
      "mndwi_after_min": 0.1,
      "mndwi_before_max": 0.0,
      "slope_max_deg": 5.0,
      "height_above_low_max_m": 15.0,
      "low_ground_window_m": 2000.0,
      "min_area_ha": 2.0,
      "road_buffer_m": 20.0,
      "place_distance_m": 5000.0
    },
    "masks": [
      "slopes steeper than 5° (Copernicus DEM GLO-30)",
      "ground more than 15 m above the lowest land nearby",
      "permanent water (ESA WorldCover 2021) and water already present in the before images",
      "built-up land for radar (buildings scatter radar and hide water)",
      "cloud and cloud shadow for optical (Sentinel-2 scene classification)"
    ],
    "confidence": {
      "higher": "two or more independent observations each detect new water over at least a quarter of the area",
      "moderate": "one observation, or several covering only small parts of the area"
    },
    "not_measured": [
      "confirmed flood extent",
      "flood depth",
      "water that drained before the satellite passes",
      "flooding under tree cover or among buildings",
      "casualties or damage",
      "patches smaller than 2 ha"
    ]
  },
  "analysis": {
    "grid": {
      "crs": "EPSG:32644",
      "pixel_m": 20.0,
      "width": 4833,
      "height": 4993,
      "bounds": [
        387320.0,
        1704780.0,
        483980.0,
        1804640.0
      ]
    },
    "observations": [
      {
        "key": "descending-92",
        "sensor": "Sentinel-1 radar",
        "label": "Sentinel-1, 9 Nov (descending)",
        "date": "2026-11-09",
        "before_label": "16 Oct",
        "cross_geometry": false,
        "valid_pct": 100.0,
        "detected_ha": 15396.0
      },
      {
        "key": "sentinel-2",
        "sensor": "Sentinel-2 optical",
        "label": "Sentinel-2, 10 and 12 Nov",
        "date": "2026-11-12",
        "before_label": "1, 6 and 26 Oct 2026",
        "cross_geometry": false,
        "valid_pct": 93.7,
        "detected_ha": 25348.1
      }
    ],
    "candidate_count": 1739,
    "candidate_area_ha": 26398.9,
    "candidate_area_ha_by_confidence": {
      "higher": 15955.3,
      "moderate": 10443.6
    },
    "candidate_count_by_confidence": {
      "higher": 362,
      "moderate": 1377
    },
    "landcover_ha": {
      "tree cover": 225.4,
      "shrubland": 388.4,
      "grassland": 204.7,
      "cropland": 24125.3,
      "built-up": 15.2,
      "bare or sparse vegetation": 970.4,
      "permanent water": 25.6,
      "herbaceous wetland": 438.1,
      "mangroves": 5.7
    },
    "pre_event_water_ha": 19075.0,
    "eligible_pct": 56.1,
    "road_length_near_candidates_m": 79751.0,
    "reference_comparison": null,
    "osm_retrieved": "2026-11-13T17:12:13Z"
  },
  "imagery": {
    "crs": "EPSG:32644",
    "display_stack": "descending-92",
    "sentinel1_rtc": {
      "descending-92": {
        "label": "Sentinel-1, 9 Nov (descending)",
        "date": "2026-11-09",
        "before_label": "16 Oct",
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          "S1D_IW_GRDH_1SDV_20261016T003011_20261016T003036_005033_009838_rtc",
          "S1D_IW_GRDH_1SDV_20261016T003036_20261016T003101_005033_009838_rtc"
        ],
        "after": [
          "S1D_IW_GRDH_1SDV_20261109T003011_20261109T003036_005383_00A43F_rtc",
          "S1D_IW_GRDH_1SDV_20261109T003036_20261109T003101_005383_00A43F_rtc"
        ]
      }
    },
    "sentinel2": {
      "before": [
        "S2B_MSIL2A_20261026T045909_R119_T44QMD_20261026T103133",
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      "after": [
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      ],
      "before_label": "1, 6 and 26 Oct 2026",
      "after_label": "Sentinel-2, 10 and 12 Nov",
      "after_date": "2026-11-12",
      "after_display_label": "10 and 12 Nov 2026"
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    "dem": [
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    "worldcover": [
      "ESA_WorldCover_10m_2021_v200_N15E078",
      "ESA_WorldCover_10m_2021_v200_N15E081"
    ]
  },
  "sources": [
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      "name": "Copernicus Sentinel-1 radiometrically terrain-corrected backscatter (from GRD)",
      "url": "https://planetarycomputer.microsoft.com/dataset/sentinel-1-rtc",
      "licence": "Copernicus Sentinel data terms (free, full and open); RTC processing by Microsoft Planetary Computer, CC BY 4.0",
      "licence_url": "https://sentinels.copernicus.eu/documents/247904/690755/Sentinel_Data_Legal_Notice",
      "attribution": "Contains modified Copernicus Sentinel data [2026]"
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      "name": "Copernicus Sentinel-2 Level-2A surface reflectance",
      "url": "https://planetarycomputer.microsoft.com/dataset/sentinel-2-l2a",
      "licence": "Copernicus Sentinel data terms (free, full and open)",
      "licence_url": "https://sentinels.copernicus.eu/documents/247904/690755/Sentinel_Data_Legal_Notice",
      "attribution": "Contains modified Copernicus Sentinel data [2026]"
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      "name": "Copernicus DEM GLO-30",
      "url": "https://planetarycomputer.microsoft.com/dataset/cop-dem-glo-30",
      "licence": "Copernicus DEM licence (free, worldwide, with attribution)",
      "licence_url": "https://spacedata.copernicus.eu/documents/20123/121286/CSCDA_ESA_Mission-specific+Annex_31_Oct_22.pdf",
      "attribution": "Copernicus DEM GLO-30 © DLR e.V. 2010–2014 and © Airbus Defence and Space GmbH 2014–2018, provided under COPERNICUS by the European Union and ESA"
    },
    {
      "name": "ESA WorldCover 10 m 2021 v200",
      "url": "https://planetarycomputer.microsoft.com/dataset/esa-worldcover",
      "licence": "CC BY 4.0",
      "licence_url": "https://creativecommons.org/licenses/by/4.0/",
      "attribution": "© ESA WorldCover project 2021 / Contains modified Copernicus Sentinel data (2021) processed by ESA WorldCover consortium"
    },
    {
      "name": "OpenStreetMap main roads, places and rivers (Overpass API)",
      "url": "https://www.openstreetmap.org/copyright",
      "licence": "Open Database Licence (ODbL) 1.0",
      "licence_url": "https://opendatacommons.org/licenses/odbl/1-0/",
      "attribution": "© OpenStreetMap contributors, available under the Open Database Licence (ODbL)"
    },
    {
      "name": "EOX Maps WMS (OpenStreetMap locator)",
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      "licence": "OpenStreetMap data under ODbL; rendering by EOX and MapServer",
      "licence_url": "https://opendatacommons.org/licenses/odbl/1-0/",
      "attribution": "Locator: data © OpenStreetMap contributors (ODbL); rendering © EOX and MapServer"
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  ],
  "references": [
    {
      "publisher": "GDACS (UN and European Commission)",
      "title": "Tropical cyclone MURASU-26: Red alert, 1–3 November 2026",
      "date": "November 2026",
      "url": "https://www.gdacs.org/report.aspx?eventid=1001346&episodeid=10&eventtype=TC"
    },
    {
      "publisher": "India Meteorological Department",
      "title": "Severe cyclonic storm Murasu: bulletin issued at 11:20 IST on 3 November 2026",
      "date": "3 November 2026",
      "url": "https://mausam.imd.gov.in/backend/assets/cyclone_pdf/24_Hourly_Bulletin_031126_1030IST.pdf"
    },
    {
      "publisher": "Hindustan Times",
      "title": "Cyclone Murasu makes landfall in Andhra Pradesh, triggers heavy rain; thousands evacuated",
      "date": "3 November 2026",
      "url": "https://www.hindustantimes.com/india-news/cyclone-murasu-makes-landfall-in-andhra-pradesh-triggers-heavy-rain-thousands-evacuated-coastal-areas-on-alert-101793641721774.html"
    },
    {
      "publisher": "The News Minute",
      "title": "Cyclone Murasu: 8 dead, CM Naidu estimates damages at Rs 1,919 cr in Andhra",
      "date": "5 November 2026",
      "url": "https://www.thenewsminute.com/andhra-pradesh/cyclone-murasu-8-dead-cm-naidu-estimates-damages-at-rs-1919-cr-in-andhra"
    },
    {
      "publisher": "Deccan Chronicle",
      "title": "Murasu causes crop damage, flooding in south coastal AP",
      "date": "3 November 2026",
      "url": "https://www.deccanchronicle.com/southern-states/andhra-pradesh/murasu-causes-crop-damage-flooding-in-south-coastal-ap-2001480"
    },
    {
      "publisher": "The Times of India",
      "title": "Cyclone 'Murasu' triggers heavy rainfall, inundation in coastal AP; Guntur records 298 mm, Ponnur 313 mm",
      "date": "3 November 2026",
      "url": "https://timesofindia.indiatimes.com/city/vijayawada/cyclone-murasu-triggers-heavy-rainfall-inundation-in-coastal-ap-guntur-records-298-mm-ponnur-313-mm/articleshow/135485414.cms"
    },
    {
      "publisher": "NRSC/ISRO National Database for Emergency Management",
      "title": "Andhra Pradesh cyclone: water accumulated areas from RISAT-1A, 5 November 2026 18:00",
      "date": "5 November 2026",
      "url": "https://ndem.nrsc.gov.in/documents/Disaster_Document/2026/AP/apcyclone50dsc05112026_1800hrs/apcyclone50dsc05112026_1800hrs_map.pdf"
    },
    {
      "publisher": "NRSC/ISRO National Database for Emergency Management",
      "title": "Andhra Pradesh cyclone: water accumulated areas from RCM, 6 November 2026 06:00",
      "date": "6 November 2026",
      "url": "https://ndem.nrsc.gov.in/documents/Disaster_Document/2026/AP/apcyclone50dsc06112026_0600hrs/apcyclone50dsc06112026_0600hrs_map.pdf"
    }
  ],
  "cross_check": "India's National Remote Sensing Centre (NRSC/ISRO) published maps of water-accumulated areas in Andhra Pradesh from RISAT-1A radar on 5 November and from RADARSAT Constellation Mission radar on 6 November (see References). Those maps are not openly licensed, so they are not reproduced or compared pixel by pixel here, but they offer an independent official view of where water lay a few days before our images.",
  "revision": 1,
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