fix(weather): accept Rust profile shape in SoundingParams + WeatherLayers

The Rust f01..f18 pipeline writes ProfilesFile cells, and the Rust
hrrr_points worker writes hrrr_profiles rows, with profile entries
keyed "pres_mb" / "hght_m" / "tmpc" / "dwpc" (string keys pre-
atomization; atom keys post-ProfilesFile.read). Elixir's
SoundingParams.derive and WeatherLayers.sort_profile filtered on
"pres" / "hght" — so every derived field returned nil for any
Rust-provided profile.

Visible symptoms on /weather: N-gradient, Refractivity, T @ 850mb,
Td @ 850mb, Lapse Rate, Inversion, Inv. Base all rendered no overlay.
For per-contact analysis, min_refractivity_gradient from the Rust
HRRR point worker's rows silently dropped.

- SoundingParams.normalize_profile_entry/1: single-source normalizer
  accepting legacy, Rust-string, and Rust-atom shapes; returns the
  canonical "pres"/"hght"/"tmpc"/"dwpc"/"drct"/"sknt" shape.
- SoundingParams.derive/1 and WeatherLayers.sort_profile/1 both run
  every entry through it before the rest of the existing logic.
- Weather.build_grid_cache_row/4 now falls back to native_min_gradient
  when SoundingParams can't derive one (surface-only profiles).

Also:
- Default /weather overlay changed to Temperature (LiveView assign +
  JS fallback in the hook's dataset default) per user request.

assets/js/weather_map_hook.ts

@@ -390,7 +390,7 @@ export const WeatherMap: WeatherMapHook = {
     this.weatherOverlay = null
     this.weatherData = []
     this.gridLookup = new Map()
-    this.selectedLayer = (this.el.dataset.selectedLayer || "refractivity_gradient") as LayerId
+    this.selectedLayer = (this.el.dataset.selectedLayer || "temperature") as LayerId
 
     const storedLayer = localStorage.getItem("weatherMap.selectedLayer")
     if (storedLayer && storedLayer in COLOR_SCALES && storedLayer !== this.selectedLayer) {

lib/microwaveprop/weather.ex

@@ -895,13 +895,15 @@ defmodule Microwaveprop.Weather do
     if is_nil(temp_c) or temp_c < -80 or temp_c > 60 do
       []
     else
+      # `SoundingParams.derive` + `WeatherLayers.sort_profile` both call
+      # `SoundingParams.normalize_profile_entry/1` internally, so we can
+      # hand either shape (legacy string-keyed or Rust atom-keyed) through
+      # unchanged. `surface_refractivity` and `min_refractivity_gradient`
+      # aren't persisted by Rust — they flow through from the per-cell
+      # sounding derivation; `refractivity_gradient` falls back to the
+      # `native_min_gradient` scalar the Rust f01..f18 pipeline does write.
       sounding = derive_sounding(profile[:profile])
 
-      # Prefer explicit values from the profile map (Rust-written ProfilesFile
-      # persists derived sounding params alongside the raw profile) and fall
-      # back to deriving from the profile list when absent. `prefer/3` uses
-      # `Map.fetch/2` so a legitimate `false` / `0` persisted value is not
-      # silently clobbered by a `||` fallback.
       row = %{
         lat: lat,
         lon: lon,
@@ -910,7 +912,9 @@ defmodule Microwaveprop.Weather do
         dewpoint_depression: depression(temp_c, profile[:surface_dewpoint_c]),
         bl_height: profile[:hpbl_m],
         pwat: profile[:pwat_mm],
-        refractivity_gradient: prefer(profile, :min_refractivity_gradient, sounding[:min_refractivity_gradient]),
+        refractivity_gradient:
+          prefer(profile, :min_refractivity_gradient, sounding[:min_refractivity_gradient]) ||
+            profile[:native_min_gradient],
         ducting: prefer(profile, :ducting_detected, sounding[:ducting_detected]),
         surface_pressure_mb: profile[:surface_pressure_mb],
         surface_temp_c: temp_c,

lib/microwaveprop/weather/sounding_params.ex

@@ -17,13 +17,22 @@ defmodule Microwaveprop.Weather.SoundingParams do
   @doc """
   Derive atmospheric propagation parameters from a sounding profile.
 
-  Profile is a list of maps with keys: "pres", "hght", "tmpc", "dwpc", "drct", "sknt".
+  Accepts either:
-  Returns nil if fewer than 3 valid levels.
+    * Legacy shape — string keys `"pres"` / `"hght"` / `"tmpc"` / `"dwpc"`
+      (Elixir's HrrrClient, NARR, GEFS, UWYO clients).
+    * Rust shape — `"pres_mb"` / `"hght_m"` / `"tmpc"` / `"dwpc"` (string
+      or atom keys from the Rust hrrr_points worker and the f01..f18
+      ProfilesFile cells).
+
+  Both are normalized at entry to the canonical legacy shape so the
+  rest of this module can assume `p["pres"]` / `p["hght"]` without per-
+  source branching. Returns nil if fewer than 3 valid levels.
   """
   @spec derive([map()]) :: map() | nil
   def derive(profile) when is_list(profile) do
     sorted =
       profile
+      |> Enum.map(&normalize_profile_entry/1)
       |> Enum.filter(fn p -> p["pres"] != nil and p["tmpc"] != nil and p["hght"] != nil end)
       |> Enum.sort_by(fn p -> p["pres"] end, :desc)
 
@@ -34,6 +43,36 @@ defmodule Microwaveprop.Weather.SoundingParams do
     end
   end
 
+  @doc """
+  Normalize a single profile entry to the canonical string-keyed shape
+  (`"pres"` / `"hght"` / `"tmpc"` / `"dwpc"`). Tolerates:
+    * The already-canonical shape (returned unchanged).
+    * Rust's `"pres_mb"` / `"hght_m"` string keys.
+    * Atom-keyed variants from `ProfilesFile.read/1` after Elixir's
+      atomization pass.
+
+  Exposed so `WeatherLayers` and other profile consumers share the
+  same input contract.
+  """
+  @spec normalize_profile_entry(map()) :: map()
+  def normalize_profile_entry(%{"pres" => _} = entry), do: entry
+
+  def normalize_profile_entry(entry) when is_map(entry) do
+    %{
+      "pres" => pick(entry, ["pres_mb", :pres_mb, :pres]),
+      "hght" => pick(entry, ["hght_m", :hght_m, "hght", :hght]),
+      "tmpc" => pick(entry, ["tmpc", :tmpc]),
+      "dwpc" => pick(entry, ["dwpc", :dwpc]),
+      "drct" => pick(entry, ["drct", :drct]),
+      "sknt" => pick(entry, ["sknt", :sknt])
+    }
+  end
+
+  def normalize_profile_entry(entry), do: entry
+
+  # Return the first non-nil value found under any of the candidate keys.
+  defp pick(map, keys), do: Enum.find_value(keys, fn k -> Map.get(map, k) end)
+
   defp do_derive(sorted) do
     sfc = hd(sorted)
     sfc_hght = sfc["hght"]

lib/microwaveprop/weather/weather_layers.ex

@@ -34,7 +34,12 @@ defmodule Microwaveprop.Weather.WeatherLayers do
   defp sort_profile([]), do: []
 
   defp sort_profile(profile) do
+    # Accept either legacy string keys (`"pres"`, `"hght"`) or the
+    # Rust ProfilesFile shape (`"pres_mb"` / atom `:pres_mb` post-atomization
+    # via ProfilesFile.read). `SoundingParams.normalize_profile_entry/1`
+    # is the single source of truth for that coercion.
     profile
+    |> Enum.map(&SoundingParams.normalize_profile_entry/1)
     |> Enum.filter(fn p -> p["pres"] != nil and p["tmpc"] != nil and p["hght"] != nil end)
     |> Enum.sort_by(fn p -> p["pres"] end, :desc)
   end

lib/microwaveprop_web/live/weather_map_live.ex

@@ -168,7 +168,7 @@ defmodule MicrowavepropWeb.WeatherMapLive do
      assign(socket,
        page_title: "Weather Map",
        layers: @layers,
-       selected_layer: "refractivity_gradient",
+       selected_layer: "temperature",
        initial_data_json: Jason.encode!(data),
        valid_time: initial_vt,
        valid_times: valid_times,

test/microwaveprop/weather_test.exs

@@ -26,6 +26,43 @@ defmodule Microwaveprop.WeatherTest do
     lon: -97.30
   }
 
+  describe "build_grid_cache_rows/3 — Rust ProfilesFile shape" do
+    @rust_profile %{
+      surface_temp_c: 25.0,
+      surface_dewpoint_c: 18.0,
+      surface_pressure_mb: 1013.0,
+      hpbl_m: 1500.0,
+      pwat_mm: 35.0,
+      native_min_gradient: -120.0,
+      profile: [
+        %{pres_mb: 1013.0, hght_m: 50.0, tmpc: 25.0, dwpc: 18.0},
+        %{pres_mb: 925.0, hght_m: 800.0, tmpc: 18.0, dwpc: 14.0},
+        %{pres_mb: 850.0, hght_m: 1500.0, tmpc: 12.0, dwpc: 9.0},
+        %{pres_mb: 700.0, hght_m: 3000.0, tmpc: 0.0, dwpc: -5.0}
+      ]
+    }
+
+    test "derives upper-air + refractivity fields from an atom-keyed Rust profile" do
+      grid_data = %{{32.875, -97.0} => @rust_profile}
+      valid_time = ~U[2026-04-24 16:00:00Z]
+
+      [row] = Weather.build_grid_cache_rows(grid_data, valid_time)
+
+      # Upper-air fields flow from the normalized profile.
+      assert is_number(row.temp_850mb)
+      assert is_number(row.dewpoint_850mb)
+      assert is_number(row.lapse_rate)
+      assert is_number(row.inversion_strength)
+
+      # Surface refractivity is derived when Rust doesn't emit it.
+      assert is_number(row.surface_refractivity)
+
+      # Gradient uses the native_min_gradient fallback when
+      # SoundingParams can't derive one (or matches when it can).
+      assert is_number(row.refractivity_gradient)
+    end
+  end
+
   describe "reconcile_weather_statuses/0" do
     alias Microwaveprop.Radio
     alias Microwaveprop.Radio.Contact