Climate evidence helps people compare one part of a destination alongside other retirement decisions. Retirement Lists calculates Climate Comfort for 987 destinations by combining three required inputs: Summer Feel, Winter Feel, and the share of the year counted as comfortable months.
Climate Comfort describes how the product organizes destination evidence. It is not a forecast, a promise of personal comfort, or advice about where someone should live.
What Climate Comfort includes
Climate Comfort uses three equally weighted inputs:
- Summer Feel
- Winter Feel
- Comfortable Months percentage
The exact calculation is:
Comfortable Months percentage = comfortable_months ÷ 12 × 100
Climate Comfort = round((Summer Feel + Winter Feel + Comfortable Months percentage) ÷ 3)
The result is rounded after the three inputs are averaged.
Summer Heat
Summer Heat reflects the annual frequency of days above 90°F. Its child methodology owns the thresholds, geographic evidence, data periods, exclusions, and limitations.
Winter Comfort
Winter Comfort reflects the annual frequency of days below freezing. Its child methodology owns the thresholds, geographic evidence, fallback evidence, exclusions, and limitations.
Comfortable months
The frozen release contains 987 Comfortable Months records. Its recorded methodology is: “Count of months passing the NASA POWER daily-derived comfort window, 2019-2023, at the city coordinate.”
The exact formula used to decide whether a month passes that comfort window is not preserved in the frozen release contract. This page therefore does not infer or publish a more specific qualification rule.
Where Climate Comfort is used
Climate Comfort is available for 987 destinations. When all three required inputs are present, it may be:
- displayed on destination pages;
- used in filters and sorting;
- included in Fit;
- applied through hard constraints; and
- shown in Compare.
These uses organize destination evidence inside Retirement Lists. They do not determine whether a climate will suit a particular person.
Comfortable Months also has a narrower standalone eligibility contract. It may be displayed and used in filters, sorting, and Compare. As a standalone component, it is not eligible for Fit or hard constraints.
What happens when an input is missing
All three inputs are required. If Summer Feel, Winter Feel, or comfortable months is unavailable, Climate Comfort fails closed: Retirement Lists does not calculate the result from the remaining inputs.
A Comfortable Months record also requires the applicable NASA POWER daily-derived source evidence. Missing required evidence is not replaced with an assumed value.
Evidence periods and freshness
Climate components do not all use one uniform evidence period. Temperature inputs may draw from recent daily evidence, longer station periods, or a limited climatology fallback. Comfortable Months uses NASA POWER daily documentation with an effective period of January 1, 2019 through December 31, 2023. Air Quality uses a separate evidence contract and is not part of the Climate Comfort formula.
Retrieval and packet-generation timestamps are not publisher observation dates or source-update dates. No publisher update dates or Climate editorial review date are recorded, so none should be displayed as “source updated” or “last reviewed.”
What Climate Comfort does not show
Climate Comfort is a simplified comparison measure. An average can conceal meaningful differences between summer heat, winter conditions, and the number of comfortable months.
It does not include long-term air quality, neighborhood microclimates, home heating or cooling conditions, or an individual’s health needs and temperature preferences.
Continue your research
Included, excluded, and eligibility contract
| Item | Contract |
|---|---|
| Included | Summer Feel, Winter Feel, and Comfortable Months percentage |
| Excluded | Air Quality and any condition not represented by the three stated inputs |
| Missing behavior | Any missing required input or source evidence prevents Climate Comfort from being calculated |
| Coverage | 987 destinations |
| Display eligibility | Eligible when all three inputs are present |
| Decision eligibility | Eligible for filter, sort, Fit, hard constraints, and Compare |
Comfortable Months standalone eligibility
| Use | Eligible |
|---|---|
| Display | Yes |
| Filter | Yes |
| Sort | Yes |
| Fit | No |
| Hard constraints | No |
| Compare | Yes |
Source ledger
| Organization | URL | Supported claim or input | Geography | Data period | Observed/source-updated | Last reviewed | Evidence type | Limitation |
|---|---|---|---|---|---|---|---|---|
| Retirement Lists | No separate public source URL supplied | Three-input Climate Comfort formula, required-input rule, coverage, and product eligibility | 987 destinations | Component-specific periods | Source-update date unavailable | Not recorded | Executable product calculation | The exact formula used to qualify a comfortable month is not preserved in the frozen release contract |
| NASA POWER | https://power.larc.nasa.gov/docs/services/api/temporal/daily/ | Daily evidence supporting the 987 Comfortable Months records | 987 destination coordinates | 2019-01-01–2023-12-31 | Source-update date unavailable | Not recorded | Daily modeled/reanalysis delivery documentation | The release records a daily-derived comfort window but does not preserve its exact qualification formula |
Sources and review
- NASA POWER
Daily evidence supporting the 987 Comfortable Months records.