The reported population density changes based on data from Data for Good at Meta primarily measure digital infrastructure failure, not physical displacement, given the widespread outage conditions following Hurricane Melissa. Facebook mobility data requires functioning mobile devices, cellular networks, and internet connectivity. All of these were compromised by power outages affecting 72-77% of Jamaica, with complete outages in St. Elizabeth, Westmoreland, and Hanover (CBS News, ABC News).

Western parishes experienced catastrophic infrastructure damage.

The 60-87% “decreases” correlate with power outages, indicating 600,000-700,000 people are present but digitally invisible, not evacuated.

Montego Bay in Saint James experienced severe flooding (CNN). Black River in St. Elizabeth was described as “ground zero” with 90% of roofs destroyed (CBS News) Available evidence suggest that the majority of residents remain in these areas without connectivity.

Infrastructure failures were far less severe in eastern parishes which maintained higher levels of connectivity

Saint Andrew: +13% (13,673→15,445) represents maintained urban infrastructure plus limited evacuee reception.
Saint Catherine: 0% (stable at ~11,500) indicates infrastructure resilience
Saint Thomas: -1% (minimal change) shows eastern parishes largely unaffected

Temporal Pattern Analysis

The time-series graphs showing sharp declines on October 29-30 represent cascading infrastructure failure, not mass evacuation:

October 28 (landfall): Initial power outages; some devices operating on battery
October 29-30: Battery depletion, cell tower failures, backup generator fuel exhaustion
November 1: Stable low connectivity indicating sustained grid collapse requiring weeks of repair

The absence of recovery trends by November 1st reflects prolonged power outages, not prolonged displacement. The 72% without power (ABC News) closely matches the ~70% average “population decrease” across affected parishes.

Elderly Population at Heightened Risk

The parishes with the most severe connectivity loss harbor disproportionately high elderly populations who are likely present but unreachable. St. Elizabeth, for instance, has a total population of 163K+ people, of which 14% are over the age of 60. If we understand the mobility data decline of -65% to represent mostly connectivity loss, that would mean that at least 14K+ elderly people are without connectivity in that area.

Aggregated over the country, approximately 70,000-80,000 elderly individuals in predominantly offline parishes face compounding vulnerabilities:

Chronic Disease Management: Unable to communicate medication needs, refill requests, or medical emergencies. In prolonged power outages, refrigerated medications (insulin, biologics) spoil within 24-48 hours.
Digital Exclusion: Elderly populations have lower baseline smartphone adoption and digital literacy. Even when connectivity partially returns, they are least likely to appear in mobility data or use digital reporting tools.
Physical Isolation: With 90% of roofs destroyed in areas like Black River CBS News and roads impassable, elderly individuals with limited mobility cannot reach functioning healthcare facilities or evacuation points without physical assistance.

Child Vulnerability in Blackout Zones

Parishes with higher concentrations of young children experienced severe connectivity loss.

Approximately 35,000-40,000 children under age 5 remain in offline zones, creating urgent pediatric health risks:

Dehydration and Waterborne Disease: Post-hurricane flooding and compromised water systems put young children at highest risk. Without communication infrastructure, parents cannot report diarrheal illness, dehydration, or other acute conditions requiring immediate intervention.
Immunization Disruption: Routine vaccination schedules interrupted; refrigerated vaccines likely spoiled in healthcare facilities without backup power.
Acute Respiratory Illness: Storm damage releasing mold, dust, and debris combined with crowded shelter conditions creates respiratory hazard environments for young children.
Family Separation: With 13,000-25,000 people in shelters (CBS News, ABC News), some families may be separated across multiple facilities or between shelters and damaged homes. Digital communication loss constrains family reunification efforts.

Limited Actual Migration

The mobility matrix shows modest movement patterns that likely reflect connectivity disparities rather than mass evacuation.

Saint Andrew +51%: Movement from outlying areas to central Kingston (both zones with connectivity), not large-scale migration from offline western parishes

Denominator effect: When 60-80% of rural users go offline, urban users appear as a larger proportion of total visible users Actual evacuee scale: 13,000-25,000 people confirmed in 521 shelters (CBS News, ABC News), suggesting true evacuation affects 50,000-150,000 people (5-15% of affected parishes), not the 350,000-400,000 implied by raw mobility data

140,000 Potentially “Cut Off” Population

Officials reported 140,000 people were “cut off” (CNN) by the storm—these are precisely the populations invisible in the mobility data. They are:

Physically isolated by road damage and debris
Digitally isolated by power and connectivity loss
Present in their communities but unable to communicate needs or report emergencies
Potentially most vulnerable due to inability to request assistance